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1.
BMC Ophthalmol ; 24(1): 231, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38822280

RESUMEN

BACKGROUND: The main purpose of this paper is to introduce a method that can accurately locate the posterior capsule of the lens to facilitate a relatively complete resection of the anterior vitreous body. METHODS: A total of 51 patients in the experimental group and control group were enrolled in this study. Phacoemulsification combined with vitrectomy was performed in all cases. After the cataract procedure was completed in the control group, the surgeon performed a conventional anterior vitrectomy with the operative eye. In the experimental group, anterior vitrectomy was performed according to the threadiness corrugation of the posterior capsule of the lens. During the operation, with the help of triamcinolone, two surgeons confirmed the resection of the anterior vitreous cortex; the best corrected visual acuity and intraocular pressure of all patients were recorded at 1 week, 1 month and 3 months after surgery. RESULTS: Fifty patients underwent phacoemulsification combined with vitrectomy, except one patient in the experimental group who was lost to follow-up. After surgery, no significant complications were observed in all patients except two patients in the control group with temporary increases in intraocular pressure. There was no significant difference in preoperative visual acuity between the two groups (t = 0.83, P = 0.25). Both groups had varying degrees of improvement in best corrected visual acuity at 1 week, 1 month and 3 months after surgery. Moreover, there was no significant difference in BCVA between the two groups at the three follow-up time points (t=-1.15, -1.65, -1.09, P = 0.53, 0.21, 0.23). After surgery, no significant complications were observed in all patients except two patients in the control group with temporary increases in intraocular pressure. Incomplete resection of the anterior vitreous cortex was observed in 2 patients in each group, but there was no significant difference (χ2 = 7.81, P > 0.05). CONCLUSION: In the process of cataract surgery combined with vitrectomy, thready corrugation appears in the posterior capsule of the lens and is an important sign of its localization. Anterior vitrectomy can be accomplished safely and effectively with the help of thread-like corrugation, and the surgical effect is almost the same as that of traditional surgery. Especially suitable for beginners in vitreous surgery.


Asunto(s)
Presión Intraocular , Facoemulsificación , Agudeza Visual , Vitrectomía , Cuerpo Vítreo , Humanos , Vitrectomía/métodos , Facoemulsificación/métodos , Femenino , Masculino , Anciano , Persona de Mediana Edad , Cuerpo Vítreo/cirugía , Presión Intraocular/fisiología , Cápsula Posterior del Cristalino/cirugía , Anciano de 80 o más Años
2.
Carcinogenesis ; 42(4): 587-600, 2021 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-33151304

RESUMEN

c-Met hyperactivity has been observed in numerous neoplasms. Several researchers have shown that the abnormal activation of c-Met is mainly caused by transcriptional activation. However, the molecular mechanism behind this transcriptional regulation is poorly understood. Here, we suggest that Smad3 negatively regulates the expression and activation of c-Met via a transcriptional mechanism. We explore the molecular mechanisms that underlie Smad3-induced c-Met transcription inhibition. We found in contrast to the high expression of c-Met, Smad3 showed low protein and mRNA levels. Smad3 and c-Met expressions were inconsistent between lung cancer tissues and cell lines. We also found that Smad3 overexpression suppresses whereas Smad3 knockdown significantly promotes Epithelial-Mesenchymal Transition and production of the angiogenic factors VEGF, CTGF and COX-2 through the ERK1/2 pathway. In addition, Smad3 overexpression decreases whereas Smad3 knockdown significantly increases protein and mRNA levels of invasion-related ß-catenin and FAK through the PI3K/Akt pathway. Furthermore, using the chromatin immunoprecipitation analysis method, we demonstrate that a transcriptional regulatory complex consisting of HDAC1, Smad3 and mSin3A binds to the promoter of the c-Met gene. By either silencing endogenous mSin3A expression with siRNA or by pretreating cells with a specific HDAC1 inhibitor (MS-275), Smad3-induced transcriptional suppression of c-Met could be effectively attenuated. These results demonstrate that Smad3-induced inhibition of c-Met transcription depends on of a functional transcriptional regulatory complex that includes Smad3, mSin3A and HDAC1 at the c-Met promoter. Collectively, our findings reveal a new regulatory mechanism of c-Met signaling, and suggest a potential molecular target for the development of anticancer drugs.


Asunto(s)
Histona Desacetilasa 1/genética , Neoplasias Pulmonares/genética , Complejo Correpresor Histona Desacetilasa y Sin3/genética , Proteína smad3/genética , Línea Celular Tumoral , Factor de Crecimiento del Tejido Conjuntivo/genética , Ciclooxigenasa 2/genética , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Neoplasias Pulmonares/patología , Fosfatidilinositol 3-Quinasas/genética , Regiones Promotoras Genéticas/genética , Proteínas Proto-Oncogénicas c-met/genética , Activación Transcripcional/genética , Factor A de Crecimiento Endotelial Vascular/genética , beta Catenina/genética
3.
Biosci Biotechnol Biochem ; 85(5): 1128-1139, 2021 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-33693487

RESUMEN

The C-terminal of G protein-coupled receptors is now recognized as being important for G protein activation and signaling function. To detect the role of C-terminal tail in receptor activation, we used the α1b-AR, which has a long C-terminal of 164 amino acids. We constructed the intramolecular FRET sensors, in which the C-terminal was truncated to 10 (∆C-10), 20 (∆C-20), 30 (∆C-30), 50 (∆C-50), 70 (∆C-70), or 90 (∆C-90). The truncated mutants of ∆C-10, ∆C-20, or ∆C-30 cannot induce FRET signal changes and downstream ERK1/2 phosphorylation. However, the truncated mutants of ∆C-50, ∆C-70, or ∆C-90 induce significant FRET signal changes and downstream ERK1/2 phosphorylation, especially ∆C-90. This is particularly true in the case of the ∆C-90, ∆C-70, or ∆C-50 which retained the potential phosphorylation sites (Ser401, Ser404, Ser408, or Ser410). The ∆C-90 showed an increase in agonist-induced FRET signal changes and ERK1/2 phosphorylation in PKC- or endocytosis-dependent and EGFR-, src-, or ß-arrestin2-independent.


Asunto(s)
Técnicas Biosensibles , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Procesamiento Proteico-Postraduccional , Receptores Adrenérgicos alfa 1/química , Arrestina beta 2/genética , Animales , Transferencia Resonante de Energía de Fluorescencia , Expresión Génica , Genes Reporteros , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Células HEK293 , Humanos , Mesocricetus , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/genética , Fenilefrina/farmacología , Fosforilación/efectos de los fármacos , Plásmidos/química , Plásmidos/metabolismo , Dominios Proteicos , Ingeniería de Proteínas/métodos , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Receptores Adrenérgicos alfa 1/genética , Receptores Adrenérgicos alfa 1/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Serina/metabolismo , Arrestina beta 2/antagonistas & inhibidores , Arrestina beta 2/metabolismo
4.
Int J Mol Sci ; 21(8)2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32331302

RESUMEN

We fabricated nanomaterials comprising amino-functionalized and nitrogen-doped graphene quantum dots (amino-N-GQDs) and investigated their photostability and intrinsic luminescence in the near-infrared spectrum to determine their suitability as contrast agents in two-photon imaging (TPI). We observed that amino-N-GQDs with a higher amount of bonded nitrogen and amino-functionalized groups (6.2%) exhibited superior two-photon properties to those with a lower amount of such nitrogen and groups (4.9%). These materials were conjugated with polymers containing sulfur (polystyrene sulfonate, PSS) and nitrogen atoms (polyethylenimine, PEI), forming amino-N-GQD-PSS-PEI specimens (amino-N-GQD-polymers). The polymers exhibited a high quantum yield, remarkable stability, and notable two-photon properties and generated no reactive oxygen species, rendering them excellent two-photon contrast agents for bioimaging. An antiepidermal growth factor receptor (AbEGFR) was used for labeling to increase specificity. Two-photon imaging (TPI) of amino-N-GQD (6.2%)-polymer-AbEGFR-treated A431 cancer cells revealed remarkable brightness, intensity, and signal-to-noise ratios for each observation at a two-photon excitation power of 16.9 nJ pixel-1 under 30 scans and a three-dimensional (3D) depth of 105 µm, indicating that amino-N-GQD (6.2%)-polymer-AbEGFR-treated cells can achieve two-photon luminescence with 71 times less power required for two-photon autofluorescence (1322.8 nJ pixel-1 with 500 scans) of similar intensity. This economy can minimize photodamage to cells, rendering amino-N-GQD-polymers suitable for noninvasive 3D bioimaging.


Asunto(s)
Grafito/química , Imagen Molecular , Nanoestructuras/química , Nitrógeno/química , Fotones , Puntos Cuánticos , Línea Celular , Humanos , Imagenología Tridimensional , Imagen Molecular/métodos , Nanoestructuras/ultraestructura , Polímeros , Análisis Espectral , Difracción de Rayos X
5.
Cell Mol Immunol ; 18(2): 472-483, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33441966

RESUMEN

Virus-induced asthma is prevalent among children, but its underlying mechanisms are unclear. Accumulated evidence indicates that early-life respiratory virus infection increases susceptibility to allergic asthma. Nonetheless, the relationship between systemic virus infections, such as enterovirus infection, and the ensuing effects on allergic asthma development is unknown. Early-life enterovirus infection was correlated with higher risks of allergic diseases in children. Adult mice exhibited exacerbated mite allergen-induced airway inflammation following recovery from EV-A71 infection in the neonatal period. Bone marrow-derived macrophages (BMDMs) from recovered EV-A71-infected mice showed sustained innate immune memory (trained immunity) that could drive naïve T helper cells toward Th2 and Th17 cell differentiation when in contact with mites. Adoptive transfer of EV-A71-trained BMDMs induced augmented allergic inflammation in naïve recipient mice, which was inhibited by 2-deoxy-D-glucose (2-DG) pretreatment, suggesting that trained macrophages following enterovirus infection are crucial in the progression of allergic asthma later in life.


Asunto(s)
Alérgenos/efectos adversos , Asma/patología , Enterovirus Humano A/aislamiento & purificación , Infecciones por Enterovirus/complicaciones , Inmunidad Innata , Inflamación/patología , Macrófagos/inmunología , Animales , Animales Recién Nacidos , Asma/epidemiología , Asma/inmunología , Asma/virología , Diferenciación Celular , Niño , Preescolar , China/epidemiología , Infecciones por Enterovirus/virología , Humanos , Memoria Inmunológica , Inflamación/epidemiología , Inflamación/inmunología , Inflamación/virología , Macrófagos/virología , Ratones , Ratones Endogámicos BALB C , Pyroglyphidae , Células Th17/inmunología , Células Th17/virología , Células Th2/inmunología , Células Th2/virología
6.
Nanoscale Res Lett ; 15(1): 99, 2020 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-32378063

RESUMEN

We successfully prepared water-soluble fullerenol [C60(OH)46] that exhibited a high singlet oxygen quantum yield and efficiently generated reactive oxygen species. Additionally, the water-soluble C60(OH)46 with a higher composition of exposed hydroxyl groups had superior two-photon stability and characteristics compared with that with a lower composition of such groups. Therefore, the prepared fullerenol can be an effective two-photon photosensitizer. The water-soluble C60(OH)46 had favorable two-photon properties. During two-photon photodynamic therapy, the water-soluble C60(OH)46 had substantial antimicrobial activity against Escherichia coli at an ultralow-energy level of 211.2 nJ pixel-1 with 800 scans and a photoexcited wavelength of 760 nm.

7.
Curr Top Med Chem ; 19(23): 2143-2157, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31456522

RESUMEN

KRAS is a member of the murine sarcoma virus oncogene-RAS gene family. It plays an important role in the prevention, diagnosis and treatment of tumors during tumor cell growth and angiogenesis. KRAS is the most commonly mutated oncogene in human cancers, such as pancreatic cancers, colon cancers, and lung cancers. Detection of KRAS gene mutation is an important indicator for tracking the status of oncogenes, highlighting the developmental prognosis of various cancers, and the efficacy of radiotherapy and chemotherapy. However, the efficacy of different patients in clinical treatment is not the same. Since RNA interference (RNAi) technologies can specifically eliminate the expression of specific genes, these technologies have been widely used in the field of gene therapy for exploring gene function, infectious diseases and malignant tumors. RNAi refers to the phenomenon of highly specific degradation of homologous mRNA induced by double-stranded RNA (dsRNA), which is highly conserved during evolution. There are three classical RNAi technologies, including siRNA, shRNA and CRISPR-Cas9 system, and a novel synthetic lethal interaction that selectively targets KRAS mutant cancers. Therefore, the implementation of individualized targeted drug therapy has become the best choice for doctors and patients. Thus, this review focuses on the current status, future perspective and associated challenges in silencing of KRAS with RNAi technology.


Asunto(s)
Biotecnología , Neoplasias/genética , Neoplasias/terapia , Proteína Oncogénica p21(ras)/genética , Interferencia de ARN , Animales , Humanos , Mutación , Neoplasias/patología , Proteína Oncogénica p21(ras)/antagonistas & inhibidores , Proteínas Proto-Oncogénicas p21(ras)/antagonistas & inhibidores , Proteínas Proto-Oncogénicas p21(ras)/genética
8.
Nat Prod Res ; 33(22): 3210-3214, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29726713

RESUMEN

Phytochemical investigation on the ethyl acetate fraction of the leaves of Epigynum cochinchinensis led to the isolation of a new C21 pregnane glycoside, epigycoside B (1), together with three known analogues. Their structures were elucidated on the basis of extensive spectroscopic techniques, including UV, MS, and NMR experiments, as well as the chemical methods. Compound 1 displayed in vitro immunosuppressive activity against concanavalin A (Con A)/Lipopolysaccharides (LPS)-stimulated proliferation of mice splenocyte. The activity was significant as compared with control group at 50 µM concentration.


Asunto(s)
Apocynaceae/química , Glicósidos/farmacología , Inmunosupresores/aislamiento & purificación , Pregnanos/farmacología , Animales , Proliferación Celular/efectos de los fármacos , Concanavalina A/efectos de los fármacos , Glicósidos/química , Glicósidos/inmunología , Glicósidos/aislamiento & purificación , Inmunosupresores/química , Inmunosupresores/farmacología , Lipopolisacáridos , Ratones , Estructura Molecular , Hojas de la Planta/química , Pregnanos/química , Pregnanos/inmunología , Pregnanos/aislamiento & purificación , Análisis Espectral , Bazo/citología
9.
ACS Appl Mater Interfaces ; 10(17): 14438-14446, 2018 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-29620851

RESUMEN

Developing a nanomaterial, for use in highly efficient dual-modality two-photon photodynamic therapy (PDT) involving reactive oxygen species (ROS) generation and for use as a two-photon imaging contrast probe, is currently desirable. Here, graphene quantum dots (GQDs) doped with nitrogen and functionalized with an amino group (amino-N-GQDs) serving as a photosensitizer in PDT had the superior ability to generate ROS as compared to unmodified GQDs. Multidrug-resistant (MDR) species were completely eliminated at an ultralow energy (239.36 nJ pixel-1) through only 12 s two-photon excitation (TPE) in the near-infrared region (800 nm). Furthermore, the amino-N-GQDs had an absorption wavelength of approximately 800 nm, quantum yield of 0.33, strong luminescence, an absolute cross section of approximately 54 356 Göeppert-Mayer units, a lifetime of 1.09 ns, a ratio of the radiative to nonradiative decay rates of approximately 0.49, and high two-photon stability under TPE. These favorable properties enabled the amino-N-GQDs to act as a two-photon contrast probe for tracking and localizing analytes through in-depth two-photon imaging in a three-dimensional biological environment and concurrently easily eliminating MDR species through PDT.


Asunto(s)
Puntos Cuánticos , Antiinfecciosos , Resistencia a Múltiples Medicamentos , Grafito , Nitrógeno , Fotoquimioterapia , Fotones
10.
Biomaterials ; 120: 185-194, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28063357

RESUMEN

Reactive oxygen species is the main contributor to photodynamic therapy. The results of this study show that a nitrogen-doped graphene quantum dot, serving as a photosensitizer, was capable of generating a higher amount of reactive oxygen species than a nitrogen-free graphene quantum dot in photodynamic therapy when photoexcited for only 3 min of 670 nm laser exposure (0.1 W cm-2), indicating highly improved antimicrobial effects. In addition, we found that higher nitrogen-bonding compositions of graphene quantum dots more efficiently performed photodynamic therapy actions than did the lower compositions that underwent identical treatments. Furthermore, the intrinsically emitted luminescence from nitrogen-doped graphene quantum dots and high photostability simultaneously enabled it to act as a promising contrast probe for tracking and localizing bacteria in biomedical imaging. Thus, the dual modality of nitrogen-doped graphene quantum dots presents possibilities for future clinical applications, and in particular multidrug resistant bacteria.


Asunto(s)
Escherichia coli/citología , Escherichia coli/efectos de los fármacos , Microscopía Fluorescente/métodos , Fotoquimioterapia/métodos , Puntos Cuánticos/uso terapéutico , Nanomedicina Teranóstica/métodos , Antiinfecciosos/administración & dosificación , Rastreo Celular/métodos , Grafito/uso terapéutico , Mediciones Luminiscentes/métodos , Nitrógeno/química , Fármacos Fotosensibilizantes/administración & dosificación
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