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1.
Cell ; 170(3): 483-491.e8, 2017 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-28735752

RESUMEN

The cystic fibrosis transmembrane conductance regulator (CFTR) is an anion channel evolved from an ATP-binding cassette transporter. CFTR channel gating is strictly coupled to phosphorylation and ATP hydrolysis. Previously, we reported essentially identical structures of zebrafish and human CFTR in the dephosphorylated, ATP-free form. Here, we present the structure of zebrafish CFTR in the phosphorylated, ATP-bound conformation, determined by cryoelectron microscopy to 3.4 Å resolution. Comparison of the two conformations shows major structural rearrangements leading to channel opening. The phosphorylated regulatory domain is disengaged from its inhibitory position; the nucleotide-binding domains (NBDs) form a "head-to-tail" dimer upon binding ATP; and the cytoplasmic pathway, found closed off in other ATP-binding cassette transporters, is cracked open, consistent with CFTR's unique channel function. Unexpectedly, the extracellular mouth of the ion pore remains closed, indicating that local movements of the transmembrane helices can control ion access to the pore even in the NBD-dimerized conformation.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/química , Proteínas de Pez Cebra/química , Adenosina Trifosfato/metabolismo , Secuencia de Aminoácidos , Microscopía por Crioelectrón , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Humanos , Modelos Moleculares , Dominios Proteicos , Alineación de Secuencia , Proteínas de Pez Cebra/metabolismo
2.
Apoptosis ; 29(5-6): 570-585, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38127283

RESUMEN

Integrin ß6 (ITGB6), a member of the integrin family of proteins, is only present in epithelial tissues and frequently associates with integrin subunit αv to form transmembrane heterodimers named integrin αvß6. Importantly, ITGB6 determines αvß6 expression and availability. In addition to being engaged in organ fibrosis, ITGB6 is also directly linked to the emergence of cancer, periodontitis, and several potential genetic diseases. Therefore, it is of great significance to study the molecular-biological mechanism of ITGB6, which could provide novel insights for future clinical diagnosis and therapy. This review introduces the structure, distribution, and biological function of ITGB6. This review also expounds on ITGB6-related diseases, detailing the known biological effects of ITGB6.


Asunto(s)
Antígenos de Neoplasias , Fibrosis , Neoplasias , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Fibrosis/genética , Fibrosis/metabolismo , Animales , Cadenas beta de Integrinas/metabolismo , Cadenas beta de Integrinas/genética , Integrinas/metabolismo , Integrinas/genética , Periodontitis/genética , Periodontitis/metabolismo , Periodontitis/patología
3.
FASEB J ; 37(5): e22921, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37052612

RESUMEN

The serious clinical challenge of peripheral nerve injury (PNI) is nerve regeneration. Nerve conduit represents a promising strategy to contribute to nerve regeneration by bridging injured nerve gaps. However, due to a unique microenvironment of nerve tissue, autologous nerves have not been substituted by nerve conduit. Nerve regeneration after nerve conduit implantation depends on many factors, such as conductivity and biocompatibility. Therefore, Gelatin (Gel) with biocompatibility and polypyrrole (Ppy) with conductivity is highly concerned. In this paper, Gel-Ppy modified nerve conduit was fabricated with great biocompatibility and conductivity to evaluate its properties of enhancing nerve regeneration in vivo and in vitro. The proliferation of Schwann cells on Gel-Ppy modified nerve conduit was remarkably increased. Consistent with in vitro results, the Gel-Ppy nerve conduit could contribute to the regeneration of Schwann cell in vivo. The axon diameters and myelin sheath thickness were also enhanced, resulting in the amelioration of muscle atrophy, nerve conduction, and motor function recovery. To explain this interesting phenomenon, western blot results indicated that the Gel-Ppy conduit facilitated nerve regeneration via upregulating the Rap1 pathway to induce neurite outgrowth. Therefore, the above results demonstrated that Gel-Ppy modified nerve conduit could provide an acceptable microenvironment for nerve regeneration and be popularized as a novel therapeutic strategy of PNI.


Asunto(s)
Tejido Nervioso , Traumatismos de los Nervios Periféricos , Ratas , Animales , Polímeros , Gelatina , Ratas Sprague-Dawley , Pirroles , Nervio Ciático/lesiones , Traumatismos de los Nervios Periféricos/cirugía , Regeneración Nerviosa/fisiología
4.
Biomacromolecules ; 24(3): 1244-1257, 2023 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-36757021

RESUMEN

Lipidated proteins are an emerging class of hybrid biomaterials that can integrate the functional capabilities of proteins into precisely engineered nano-biomaterials with potential applications in biotechnology, nanoscience, and biomedical engineering. For instance, fatty-acid-modified elastin-like polypeptides (FAMEs) combine the hierarchical assembly of lipids with the thermoresponsive character of elastin-like polypeptides (ELPs) to form nanocarriers with emergent temperature-dependent structural (shape or size) characteristics. Here, we report the biophysical underpinnings of thermoresponsive behavior of FAMEs using computational nanoscopy, spectroscopy, scattering, and microscopy. This integrated approach revealed that temperature and molecular syntax alter the structure, contact, and hydration of lipid, lipidation site, and protein, aligning with the changes in the nanomorphology of FAMEs. These findings enable a better understanding of the biophysical consequence of lipidation in biology and the rational design of the biomaterials and therapeutics that rival the exquisite hierarchy and capabilities of biological systems.


Asunto(s)
Elastina , Proteínas Intrínsecamente Desordenadas , Elastina/química , Proteínas Intrínsecamente Desordenadas/química , Péptidos/química , Temperatura , Biotecnología , Materiales Biocompatibles/química
5.
BMC Ophthalmol ; 23(1): 471, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37985976

RESUMEN

BACKGROUND: Transepithelial corneal crosslinking (CXL) is a novel surgical approach for the treatment of keratoconus, which is a bilateral asymmetrical ophthalmological disease accompanied by progressive corneal ectasia. Silicon hydrogel (SiH) contact lenses have been extensively used in clinical ophthalmologic medicine, as a postoperative ophthalmological intervention. However, the ideal lens application duration after transepithelial CXL remains uncertain. Here, we aimed to investigate the effects and comfort of immediate corneal contact lens use after transepithelial CXL for keratoconus. METHODS: In this prospective study, 60 patients with keratoconus who underwent transepithelial CXL treatment were enrolled from September 2021 to January 2023 with a male:female ratio of 39:21, and an average age of 25.42 ± 5.47 years. The patients were divided randomly into two groups: group A contained 30 patients wearing silicone hydrogel contact lenses for 7 days postoperatively, and group B contained 30 patients wearing the same contact lenses for 3 days. Ten subjective ophthalmologic symptoms were surveyed by the patients, including pain, photophobia, foreign body sensation, tearing, burning, blurred vision, dry eyes, difficulty opening the eyes, astringency, and stinging. Ophthalmologic signs, including corneal edema and conjunctival congestion, were recorded by a single clinician on postoperative days 1, 3, and 7. RESULTS: Each surgical procedure was readily performed without complications, and both groups postoperative day 7 (P = 0.04), where group B scored (0.01 ± 0.41) lesser than group A (0.12 ± 0.29), whilst corneal edema in both groups recorded significantly different on postoperative days 5 and 7 (group A demonstrated the result of 0.17 ± 0.14 and 0.08 ± 0.11 for the respective days, whereas group B indicated 0.10 ± 0.13 and 0.03 ± 0.07 at the corresponding times). CONCLUSIONS: Immediate use of silicone hydrogel corneal lenses after transepithelial CXL effectively alleviates postoperative ocular distress, particularly with a three-day use period as the ideal duration.


Asunto(s)
Lentes de Contacto , Edema Corneal , Queratocono , Humanos , Masculino , Femenino , Adulto Joven , Adulto , Queratocono/tratamiento farmacológico , Queratocono/diagnóstico , Silicio/uso terapéutico , Estudios Prospectivos , Reticulación Corneal , Hidrogeles/uso terapéutico , Córnea , Siliconas/uso terapéutico , Reactivos de Enlaces Cruzados/uso terapéutico , Fármacos Fotosensibilizantes/uso terapéutico , Riboflavina/uso terapéutico , Rayos Ultravioleta , Topografía de la Córnea
6.
Int J Mol Sci ; 25(1)2023 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-38203568

RESUMEN

Glutathione transferases (GSTs) are a superfamily of dimeric proteins associated with the detoxification of various reactive electrophiles and responsive to a multitude of stressors. We individually substituted Lys64 and Glu78 with Ala using site-directed mutagenesis to understand the role of subunit interactions in the structure and enzymatic properties of a rice GST (OsGSTU17). The wild-type OsGSTU17 lost the conserved hydrogen bond between subunits in tau class GSTs due to conserved Tyr92 replaced with Phe92, but still exhibited high substrate activities, and thermal stability remained in its dimeric structure. The significant decrease in thermal stability and obvious changes in the structure of mutant K64A implied that conserved Lys64 might play an essential role in the structural stability of tau class GSTs. The mutant E78A, supposed to be deprived of hydrogen and salt bonds between subunits, appeared in the soluble form of dimers, even though its tertiary structure altered and stability declined dramatically. These results suggest that the hydrogen and ionic bonds provided by conserved residues are not as important for OsGSTU17 dimerization and enzymatic properties. These results further supplement our understanding of the relationship between the structure and function of GSTs and provide a theoretical basis for improving crop resistance through targeted modification of GSTs.


Asunto(s)
Glutatión Transferasa , Oryza , Glutatión Transferasa/genética , Oryza/genética , Suplementos Dietéticos , Dimerización , Hidrógeno , Polímeros
7.
Anal Chem ; 94(4): 2195-2203, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35034435

RESUMEN

Optical sensors have attracted a great deal of interest for glucose detection. However, their practical applications for continuous glucose monitoring are still constrained by operational reliability in subcutaneous tissues. Here, we show an implantable hydrogel platform embedded with luminescent polymer dots (Pdots) for sensitive and long-term glucose monitoring. We use Pdot transducer in a polyacrylamide hydrogel matrix to construct an implantable platform. The hydrogel-Pdot transducer showed bright luminescence with ratiometric response to glucose changes. The in vitro and in vivo sensitivities of the hydrogel implant were enhanced by varying the enzyme concentration and injection volume. After implantation, the hydrogel with Pdot transducer remained at the implanted site without migration for 1 month and can be removed from the subcutaneous tissue for further analysis. Our results indicate that the hydrogel-Pdot platform maintains the intrinsic sensing property with excellent stability during 1 month implantation, while fibrous capsule formation on the implant in some cases needs to be solved for long-term continuous glucose monitoring.


Asunto(s)
Hidrogeles , Polímeros , Glucemia/análisis , Automonitorización de la Glucosa Sanguínea , Glucosa , Reproducibilidad de los Resultados , Transductores
8.
Nano Lett ; 21(1): 798-805, 2021 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-33346668

RESUMEN

The concept that systemically administered nanoparticles are highly accumulated into the liver, spleen and kidney is a central paradigm in the field of nanomedicine. Here, we report that bone is an important organ for retention of small polymer nanoparticles using in vivo fluorescence imaging in the second near-infrared (NIR-II) window. We prepared different sized polymer nanoparticles with both visible and NIR-II fluorescence. NIR-II imaging reveals that the behavior of nanoparticle distribution in bone was largely dependent on the particle size. Small polymer nanoparticles of ∼15 nm diameter showed fast accumulation and long-term retention in bone, while the nanoparticles larger than ∼25 nm were dominantly distributed in liver. Confocal microscopy of bone sections indicated that the nanoparticles were largely distributed in the endothelial cells of sinusoidal vessels in bone marrow. The study provides promising opportunities for bone imaging and treatment of bone-related disease.


Asunto(s)
Nanopartículas , Polímeros , Médula Ósea/diagnóstico por imagen , Células Endoteliales , Imagen Óptica
9.
J Am Chem Soc ; 143(17): 6533-6541, 2021 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-33904731

RESUMEN

Photocatalytic biomass conversion represents an ideal way of generating syngas because of the sustainable use of biomass carbon and solar energy. However, the lack of efficient electron-proton transfer limits its efficiency. We here report an unprecedented method to simultaneously increase both the electron and proton transfer by creating surface sulfate ions on the CdS catalyst ([SO4]/CdS). Surface sulfate ion [SO4] is bifunctional, serving as the proton acceptor to promote proton transfer, and increasing the oxidation potential of the valence band to enhance electron transfer. [SO4]/CdS produces a syngas mixture from glycerol without CO2. Compared with pristine CdS, [SO4]/CdS exhibits 9-fold higher CO generation rate (0.31 mmol g-1 h-1) and 4-fold higher H2 generation (0.05 mmol g-1 h-1). A wide range of sugars, such as glucose, fructose, maltose, sucrose, xylose, lactose, insulin, and starch, were facilely converted into syngas. This study reports the pivotal effect of surface sulfate ion on electron-proton transfer in photocatalysis and provides a facile method for increasing photocatalytic efficiency.


Asunto(s)
Biocombustibles , Compuestos de Cadmio/química , Disacáridos/química , Glicerol/química , Monosacáridos/química , Polímeros/química , Sulfuros/química , Biomasa , Catálisis , Nanotubos/química , Sulfatos/química
10.
J Nanobiotechnology ; 19(1): 453, 2021 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-34963449

RESUMEN

BACKGROUND: The interactions between nanoparticles (NPs) and plasma proteins form a protein corona around NPs after entering the biological environment, which provides new biological properties to NPs and mediates their interactions with cells and biological barriers. Given the inevitable interactions, we regard nanoparticle‒protein interactions as a tool for designing protein corona-mediated drug delivery systems. Herein, we demonstrate the successful application of protein corona-mediated brain-targeted nanomicelles in the treatment of glioma, loading them with paclitaxel (PTX), and decorating them with amyloid ß-protein (Aß)-CN peptide (PTX/Aß-CN-PMs). Aß-CN peptide, like the Aß1-42 peptide, specifically binds to the lipid-binding domain of apolipoprotein E (ApoE) in vivo to form the ApoE-enriched protein corona surrounding Aß-CN-PMs (ApoE/PTX/Aß-CN-PMs). The receptor-binding domain of the ApoE then combines with low-density lipoprotein receptor (LDLr) and LDLr-related protein 1 receptor (LRP1r) expressed in the blood-brain barrier and glioma, effectively mediating brain-targeted delivery. METHODS: PTX/Aß-CN-PMs were prepared using a film hydration method with sonication, which was simple and feasible. The specific formation of the ApoE-enriched protein corona around nanoparticles was characterized by Western blotting analysis and LC-MS/MS. The in vitro physicochemical properties and in vivo anti-glioma effects of PTX/Aß-CN-PMs were also well studied. RESULTS: The average size and zeta potential of PTX/Aß-CN-PMs and ApoE/PTX/Aß-CN-PMs were 103.1 nm, 172.3 nm, 7.23 mV, and 0.715 mV, respectively. PTX was efficiently loaded into PTX/Aß-CN-PMs, and the PTX release from rhApoE/PTX/Aß-CN-PMs exhibited a sustained-release pattern in vitro. The formation of the ApoE-enriched protein corona significantly improved the cellular uptake of Aß-CN-PMs on C6 cells and human umbilical vein endothelial cells (HUVECs) and enhanced permeability to the blood-brain tumor barrier in vitro. Meanwhile, PTX/Aß-CN-PMs with ApoE-enriched protein corona had a greater ability to inhibit cell proliferation and induce cell apoptosis than taxol. Importantly, PTX/Aß-CN-PMs exhibited better anti-glioma effects and tissue distribution profile with rapid accumulation in glioma tissues in vivo and prolonged median survival of glioma-bearing mice compared to those associated with PMs without the ApoE protein corona. CONCLUSIONS: The designed PTX/Aß-CN-PMs exhibited significantly enhanced anti-glioma efficacy. Importantly, this study provided a strategy for the rational design of a protein corona-based brain-targeted drug delivery system. More crucially, we utilized the unfavorable side of the protein corona and converted it into an advantage to achieve brain-targeted drug delivery.


Asunto(s)
Antineoplásicos/administración & dosificación , Apolipoproteínas E/administración & dosificación , Encéfalo/efectos de los fármacos , Glioma/tratamiento farmacológico , Nanopartículas/administración & dosificación , Corona de Proteínas , Péptidos beta-Amiloides/administración & dosificación , Péptidos beta-Amiloides/química , Péptidos beta-Amiloides/farmacocinética , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Apolipoproteínas E/química , Apolipoproteínas E/farmacocinética , Barrera Hematoencefálica/metabolismo , Encéfalo/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Glioma/metabolismo , Humanos , Ratones , Micelas , Nanopartículas/química , Paclitaxel/administración & dosificación , Paclitaxel/química , Paclitaxel/farmacocinética , Fragmentos de Péptidos/administración & dosificación , Fragmentos de Péptidos/química , Fragmentos de Péptidos/farmacocinética , Poliésteres/administración & dosificación , Poliésteres/química , Poliésteres/farmacocinética , Polietilenglicoles/administración & dosificación , Polietilenglicoles/química , Polietilenglicoles/farmacocinética , Corona de Proteínas/química
11.
Microb Pathog ; 149: 104479, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32920149

RESUMEN

Liver disease has been reported to associate with oral microbiota. This study aimed to identify the salivary microbial structure in liver disease patients and determine whether the disease progression influence the bacterial composition. 16S rDNA high-throughput sequencing and bioinformatic analysis were used to examine oral bacterial diversity in the different status of hepatitis patients including 6 patients with Hepatitis B (Y), 6 patients with Hepatitis B Cirrhosis (YY) and 6 patients with liver cancer (C), and 6 healthy controls (T). Phylogenetic analysis revealed that the genera of Streptococcus, Prevotella, Actinomyces, Veillonella and Neisseria are predominant genus in the saliva of Y, YY, C patients and T group. Lautropia, Abiotrophia and Veillonella were enriched in Y patients, while Treponema, Selenomonas and Oribacterium were also existed in YY patients. Haemophilus, Porphyromonas and Filifactor had high abundance in C patients. The genera of Moryella, Leptotrichia, Lactobacillus, Dialister, Serratia, Enterococcus and Actinobacillus were decreased in all patient samples compared with healthy control samples which may be used for treatment of liver disease. Diversity analyses showed decreased diversity of salivary bacterial communities was discovered in the progress of the liver disease. These findings identified the oral microbiota dysbiosis in liver disease, which may providing available information and possible diagnostic biomarkers for liver patients.


Asunto(s)
Neoplasias Hepáticas , Microbiota , Humanos , Filogenia , ARN Ribosómico 16S/genética , Saliva
12.
Med Sci Monit ; 26: e922556, 2020 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-32214058

RESUMEN

BACKGROUND The aim of this study was to compare changes in the extracellular matrix after implantation of a stent that elutes a matrix metalloproteinase (MMP) inhibitor (GM6001); and to determine the effects of the GM6001-eluting stent upon prevention of in-stent restenosis (ISR). MATERIAL AND METHODS We included 48 Guangxi Bama mini-pigs in this study. A GM6001-eluting stent was placed in one iliac artery and a stent that did not elute GM6001 was placed in the contralateral iliac artery. The iliac arteries were removed at 6 hours as well as 1, 7, 14, 56, 84, and 336 days after stent placement. Arteries were analyzed for morphometry, gelatinase content, different phenotypes of vascular smooth muscle cells (VSMCs), collagen content, apoptotic rate, and cell density. RESULTS The vascular lumen areas of the GM6001 group were significantly increased and the neointimal areas were significantly reduced compared with the control group from the 7 days to the 336 days. In the 2 groups, expression of MMP-2 and MMP-9 peaked simultaneously, but GM6001-eluting stents inhibited expression of MMP-2 and MMP-9 in the vascular media and neointima (especially around the struts) significantly. In the GM6001 group, expression of tissue inhibitor of matrix metalloproteinase (TIMP)-1, TIMP-2, myosin heavy chain 10 (MYH-10, marker of the proliferative phenotype of VSMCs), collagen content, percentage of apoptotic cells, and cell density were also decreased significantly compared with those in the control group. CONCLUSIONS Use of GM6001-eluting stents resulted in persistent and potent inhibition of intimal hyperplasia, an increase in luminal area, and no obvious thrombosis in the arteries of the mini-pigs.


Asunto(s)
Reestenosis Coronaria/tratamiento farmacológico , Stents Liberadores de Fármacos , Inhibidores de la Metaloproteinasa de la Matriz/uso terapéutico , Animales , Apoptosis , Colágeno/metabolismo , Reestenosis Coronaria/complicaciones , Reestenosis Coronaria/patología , Femenino , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Cadenas Pesadas de Miosina/metabolismo , Neointima/complicaciones , Neointima/patología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Porcinos , Porcinos Enanos , Factores de Tiempo , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Inhibidor Tisular de Metaloproteinasa-2/metabolismo
13.
World J Surg Oncol ; 18(1): 46, 2020 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-32113474

RESUMEN

BACKGROUND: A vascularized fibular osteomyocutaneous flap with severe vascular crisis often results in serious consequences. This study aims to examine the clinical effect of non-vascularized fibular graft on patients with severe vascular crisis after reconstruction of the defect jaw with vascularized fibular osteomyocutaneous flap. MATERIALS AND METHODS: From December 2007 to December 2018, a total of 104 patients with jaw neoplasms that underwent reconstruction with free vascularized fibular flap were retrospectively analyzed; seven of these cases had postoperative vascular crisis during mandibular reconstruction. RESULTS: Of the seven cases with postoperative vascular crisis, the vascularized fibular flaps in three patients survived completely, thanks to early detection; two cases were completely necrotic and removed in the end, and the remaining two cases had severe vascular crisis after the removal of the soft tissue attached to the fibular flap. The non-vascular fibular grafts were retained regardless of the severe absorption after follow-ups for 25 and 69 months, respectively. CONCLUSIONS: If vascular crisis occurs following jaw reconstruction with a vascularized fibular osteomyocutaneous flap, early re-surgical exploration effectively improves the salvage rate. In addition, when a severe vascular crisis occurs, the vascularized fibular flap can be changed to a non-vascular fibular graft to reconstruct the mandibular defect, thus avoiding the serious consequences resulting from the complete failure of fibular graft.


Asunto(s)
Procedimientos Quirúrgicos Ortognáticos/métodos , Procedimientos de Cirugía Plástica/métodos , Colgajos Quirúrgicos , Adulto , Femenino , Peroné , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
14.
Angew Chem Int Ed Engl ; 59(47): 21049-21057, 2020 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-32767727

RESUMEN

Here, we describe a fluorination strategy for semiconducting polymers for the development of highly bright second near-infrared region (NIR-II) probes. Tetrafluorination yielded a fluorescence QY of 3.2 % for the polymer dots (Pdots), over a 3-fold enhancement compared to non-fluorinated counterparts. The fluorescence enhancement was attributable to a nanoscale fluorous effect in the Pdots that maintained the molecular planarity and minimized the structure distortion between the excited state and ground state, thus reducing the nonradiative relaxations. By performing through-skull and through-scalp imaging of the brain vasculature of live mice, we quantitatively analyzed the vascular morphology of transgenic brain tumors in terms of the vessel lengths, vessel branches, and vessel symmetry, which showed statistically significant differences from the wild type animals. The bright NIR-II Pdots obtained through fluorination chemistry provide insightful information for precise diagnosis of the malignancy of the brain tumor.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Fluorescencia , Colorantes Fluorescentes/química , Imagen Óptica , Polímeros/química , Puntos Cuánticos/química , Animales , Halogenación , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Tamaño de la Partícula , Semiconductores , Propiedades de Superficie
15.
Angew Chem Int Ed Engl ; 59(9): 3691-3698, 2020 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-31823447

RESUMEN

Fluorescence probes in the NIR-IIa region show drastically improved imaging owing to the reduced photon scattering and autofluorescence in biological tissues. Now, NIR-IIa polymer dots (Pdots) are developed with a dual fluorescence enhancement mechanism. First, the aggregation induced emission of phenothiazine was used to reduce the nonradiative decay pathways of the polymers in condensed states. Second, fluorescence quenching was minimized by different levels of steric hindrance to further boost the fluorescence. The resulting Pdots displayed a fluorescence QY of ca. 1.7 % in aqueous solution, suggesting an enhancement of ca. 21 times in comparison with the original polymer in tetrahydrofuran (THF) solution. Small-animal imaging by using the NIR-IIa Pdots exhibited a remarkable improvement in penetration depth and signal to background ratio, as confirmed by through-skull and through-scalp fluorescent imaging of the cerebral vasculature of live mice.


Asunto(s)
Encéfalo/diagnóstico por imagen , Colorantes Fluorescentes/química , Polímeros/química , Puntos Cuánticos/química , Espectroscopía Infrarroja Corta , Animales , Huesos/diagnóstico por imagen , Furanos/química , Ratones , Teoría Cuántica , Semiconductores
16.
Anal Chem ; 91(6): 4179-4185, 2019 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-30786718

RESUMEN

Photoblinking is a fundamental process that occurs exclusively in single fluorophores such as organic dyes, fluorescent proteins, and quantum dots. Here, we describe a strategy to achieve pronounced, high on/off ratio, and cooperative blinking in donor-acceptor multifluorophore systems. An ensemble of dye molecules doped in semiconducting polymer dots (Pdots) exhibit robust photoblinking, while the pristine Pdots and the dye in optically inert polymer matrices fluoresce continuously. Energy transfer from Pdots to dye acceptors produces photoblinking via a cooperative process, in which the bright state originates from the dye ensemble and the dark state is due to quenching of semiconducting polymer by hole polarons. Using the blinking Pdots in subcellular structures labeling, we demonstrated approximately 3.6-fold enhancement of imaging resolution in high-order super-resolution optical fluctuation nanoscopy as compared to conventional microscopy. Our findings not only demonstrate the exciting possibility of transforming a nonquantized ensemble into a single-emitter-like optical source but also provide an effective approach to generate superior photoblinking fluorescent probes for super-resolution imaging applications.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Colorantes Fluorescentes/química , Imagen Molecular/métodos , Polímeros/química , Puntos Cuánticos , Fluorescencia , Semiconductores
17.
Arch Virol ; 163(7): 1851-1861, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29582164

RESUMEN

Enterovirus 71 (EV71) is the most frequently detected causative agent in hand, foot, and mouth disease (HFMD) and is a serious threat to public health in the Asia-Pacific region. Many EV71 vaccines are under development worldwide, and although both inactivated virus vaccines and virus-like particles (VLPs) are considered to be effective, the main focus has been on inactivated EV71vaccines. There have been very few studies on EV71 VLPs. In this study, using a strategy based on HIV gag VLPs, we constructed a gag-VP1 fusion gene to generate a recombinant baculovirus expressing the EV71 structural protein VP1 together with gag, which was then used to infect TN5 cells to form VLPs. The VLPs were characterized using transmission electron microscopy, electrophoresis and staining with Coomassie blue, and Western blotting. Mice immunized with gag-VP1 VLPs showed strong humoral and cellular immune responses. Finally, immunization of female mice with gag-VP1 VLPs provided effective protection of their newborn offspring against challenge with a lethal dose EV71. These results demonstrate a successful approach for producing EV71 VP1 VLPs based on the ability of HIV gag to self-assemble, thus providing a good foundation for producing high-titered anti-EV71 antibody by immunization with VLP-based gag EV71 VP1 protein.


Asunto(s)
Anticuerpos Antivirales/inmunología , Enterovirus Humano A/inmunología , Infecciones por Enterovirus/prevención & control , Vacunas de Partículas Similares a Virus/inmunología , Proteínas Estructurales Virales/inmunología , Vacunas Virales/inmunología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/genética , Animales , Animales Recién Nacidos , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/biosíntesis , Baculoviridae/genética , Enterovirus Humano A/genética , Infecciones por Enterovirus/inmunología , Femenino , Enfermedad de Boca, Mano y Pie/inmunología , Enfermedad de Boca, Mano y Pie/prevención & control , Enfermedad de Boca, Mano y Pie/virología , Inmunidad Celular , Ratones , Pruebas de Neutralización , Proteínas Recombinantes de Fusión , Vacunación , Vacunas de Partículas Similares a Virus/administración & dosificación , Vacunas de Partículas Similares a Virus/genética , Proteínas Estructurales Virales/genética , Vacunas Virales/administración & dosificación
18.
Acta Pharmacol Sin ; 39(9): 1522-1532, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29644999

RESUMEN

Liver metabolism is commonly considered the major determinant in drug discovery and development. Many in vitro drug metabolic studies have been developed and applied to understand biotransformation. However, these methods have disadvantages, resulting in inconsistencies between in vivo and in vitro experiments. A major factor is that they are static systems that do not consider the transport process in the liver. Here we developed an in vitro dynamic metabolic system (Bio-PK metabolic system) to mimic the human pharmacokinetics of tolbutamide. Human liver microsomes (HLMs) encapsulated in a F127'-Acr-Bis hydrogel (FAB hydrogel) were placed in the incubation system. A microdialysis sampling technique was used to monitor the metabolic behavior of tolbutamide in hydrogels. The measured results in the system were used to fit the in vitro intrinsic clearance of tolbutamide with a mathematical model. Then, a PBPK model that integrated the corresponding in vitro intrinsic clearance was developed to verify the system. Compared to the traditional incubation method, reasonable PK profiles and the in vivo clearance of tolbutamide could be predicted by integrating the intrinsic clearance of tolbutamide obtained from the Bio-PK metabolic system into the PBPK model. The predicted maximum concentration (Cmax), area under the concentration-time curve (AUC), time to reach the maximum plasma concentration (Tmax) and in vivo clearance were consistent with the clinically observed data. This novel in vitro dynamic metabolic system can compensate for some limitations of traditional incubation methods; it may provide a new method for screening compounds and predicting pharmacokinetics in the early stages, supporting the development of compounds.


Asunto(s)
Microsomas Hepáticos/metabolismo , Tolbutamida/farmacocinética , Difusión , Femenino , Humanos , Hidrogeles/síntesis química , Hidrogeles/química , Masculino , Microdiálisis/métodos , Modelos Teóricos , Poloxámero/síntesis química , Poloxámero/química , Tolbutamida/metabolismo
19.
Phys Chem Chem Phys ; 19(24): 15686-15692, 2017 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-28470260

RESUMEN

The effect of three nucleoside analogue antimetabolites (5-fluorouracil, floxuridine, and gemcitabine) on the structure of Pluronic L62 copolymer micelles was investigated using small-angle neutron scattering. These antimetabolites used for cancer chemotherapy have analogous molecular structures but different molecular sizes and aqueous solubilities. It was found that the addition of the three antimetabolites slightly reduced the micellar size and aggregation number, and the micellar anisotropy. The added antimetabolites also changed the internal molecular distribution of the micelles as measured by the scattering length densities, resulting in enhanced hydration of the hydrophobic core region of the micelle. The strength of the effect was found to correlate with the molecular properties of the model drugs, i.e. a larger molecular size and a higher aqueous solubility lead to enhanced hydration of the micellar core.


Asunto(s)
Antimetabolitos/química , Micelas , Difracción de Neutrones , Polietilenglicoles/química , Glicoles de Propileno/química , Dispersión del Ángulo Pequeño , Desoxicitidina/análogos & derivados , Desoxicitidina/química , Floxuridina/química , Fluorouracilo/química , Poloxámero/química , Temperatura de Transición , Agua/química , Gemcitabina
20.
Med Sci Monit ; 23: 4462-4470, 2017 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-28917087

RESUMEN

BACKGROUND This study aimed to conduct a clinical evaluation of four restorative materials for restoration of dental wedge-shaped defect (WSD) and their impacts on periodontal tissues. MATERIAL AND METHODS A total of 280 maxillary premolars with dental WSD were selected from 106 patients; the patient cases were divided into eight groups according to different combinations of restorative materials (flowable resin composites, Dyract compomers, glass ionomer cement (GIC), light-curing composite resin), and WSD positions (approaching gingival and subgingival positions). Gingival crevicular fluid (GCF) volume, levels of aspartate aminotransferase (AST), alkaline phosphatase (ALP), and interleukin-1ß (IL-1ß) in GCF were analyzed, while probing depth (PD), plaque index (PLI), and sulcus bleeding index (SBI) were also measured. The periodontal conditions of all patients were followed prior to restoration, as well as six months and 12 months after restoration. RESULTS After six months of restoration, the overall clinical success rates of flowable resin composites, Dyract compomers, and light-curing composite resin were greater than those of GIC. GCF volume, GCF-AST, IL-1ß levels, PD, PLI, and SBI of cases restored by GIC were higher than those restored by the other three materials. After 12 months of restoration, the overall clinical success rates of flowable resin composites and Dyract compomers were greater than those of light-curing composite resin and GIC. GCF volume, GCF-AST, GCF-ALP, IL-1ß levels, PD, PLI, and SBI of cases restored by GIC were higher than those restored by the other three materials. CONCLUSIONS Our study provided evidence that the clinical efficacy of flowable resin composites, Dyract compomers, and light-curing composite resin was greater than that of GIC for restoration of dental WSD.


Asunto(s)
Prótesis Dental de Soporte Implantado/métodos , Adulto , China , Compómeros/farmacología , Resinas Compuestas , Luces de Curación Dental , Materiales Dentales , Índice de Placa Dental , Femenino , Cementos de Ionómero Vítreo/farmacología , Humanos , Masculino , Ensayo de Materiales/métodos , Prótesis Periodontal/métodos , Cementos de Resina , Resinas Sintéticas , Resultado del Tratamiento
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