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1.
Angew Chem Int Ed Engl ; 63(22): e202404077, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38494453

RESUMEN

Covalent organic frameworks (COFs) are promising photocatalysts for hydrogen peroxide (H2O2) synthesis. However, the nature of organic polymers makes the balance between high activity and stability challenging. We demonstrate that the linkage position matters in the design of robust COF photocatalysts with durable high activity without sacrificial reagents. COFs with ortho- and para-linkages (o-COFs and p-COFs) were constructed by 1,3,5-triformylphloroglucinol with benzene-, pyridine-, pyrazine-orthodiamines and paradiamines. The pyrzaine-containing o-COFs with two pyridinic nitrogen atoms exhibited a H2O2 production rate of 4396 µmol g-1 h-1 together with long-time continuous H2O2 photosynthesis performance in pure water (48 h), superior to the corresponding p-COFs. A four-step reaction mechanism is proposed by density function calculations. Moreover, the active sites and origin of stability enhancement for o-COFs are clarified. This work provides a simple and effective molecular design strategy in the design of robust COF photocatalysts for artificial H2O2 photosynthesis.

2.
Angew Chem Int Ed Engl ; : e202409799, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039911

RESUMEN

Electrocatalytic nitrate reduction reaction (NO3-RR) is an important route for sustainable NH3 synthesis and environmental remediation. Metal-organic frameworks (MOFs) are one family of promising NO3-RR electrocatalysts, however, there is plenty of room to improve in their performance, calling for new design principles. Herein, a MOF-on-MOF heterostructured electrocatalyst with interfacial dual active sites and build-in electric field is fabricated for efficient NO3-RR to NH3 production. By growing Co-HHTP (HHTP=2,3,6,7,10,11-hexahydroxytriphenylene) nanorods on Ni-BDC (BDC=1,4-benzenedicarboxylate) nanosheets, experimental and theoretical investigations demonstrate the formation of Ni-O-Co bonds at the interface of MOF-on-MOF heterostructure, leading to dual active sites tailed for NO3-RR. The Ni sites facilitate the adsorption and activation of NO3-, while the Co sites boost the H2O decomposition to supply active hydrogen (Hads) for N-containing intermediates hydrogenation on adjacent Ni sites, cooperatively reducing the energy barriers of NO3-RR process. Together with the accelerated electron transfer enabled by built-in electric field, remarkable NO3-RR performance is achieved with an NH3 yield rate of 11.46 mg h-1 cm-2 and a Faradaic efficiency of 98.4%, outperforming most reported MOF-based electrocatalysts. This work provides new insights into the design of high-performance NO3-RR electrocatalysts.

3.
Angew Chem Int Ed Engl ; : e202413866, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39175142

RESUMEN

Prussian blue analogues (PBA) are a large family of functional materials with diverse applications such as in electrochemical fields. However, their use in the emerging two-electron oxygen reduction reaction for clean production of hydrogen peroxide (H2O2) is lagging. Herein, a general solvent exchange induced reconstruction strategy is demonstrated, through which an abnormal NiNi-PBA superstructure is synthesized as a high-performance electrocatalyst for H2O2 generation. The resultant NiNi-PBA superstructure has a stoichiometric composition with saturated lattice water, and a leaf-like morphology composed of interconnected small-size nanosheets with identical orientation and predominate {210} side surface exposure. Our studies show that the Ni-N centers on {210} facets are the active sites, and the saturated lattice H2O favors a six-coordinated environment that results in high selectivity. The "perfect" structure including stoichiometric composition and ideal facet exposure leads to a high selectivity of ~100% and H2O2 yield of 5.7 mol g-1 h-1, superior to the reported MOF-based electrocatalysts and most other electrocatalysts.

4.
J Am Chem Soc ; 145(14): 7791-7799, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36896469

RESUMEN

Metal-organic frameworks (MOFs) with highly adjustable structures are an emerging family of electrocatalysts in two-electron oxygen reduction reaction (2e-ORR) for H2O2 production. However, the development of MOF-based 2e-ORR catalysts with high H2O2 selectivity and production rate remains challenging. Herein, an elaborate design with fine control over MOFs at both atomic and nano-scale is demonstrated, enabling the well-known Zn/Co bimetallic zeolite imidazole frameworks (ZnCo-ZIFs) as excellent 2e-ORR electrocatalysts. Experimental results combined with density functional theory simulation have shown that the atomic level control can regulate the role of water molecules participating in the ORR process, and the morphology control over desired facet exposure adjusts the coordination unsaturation degree of active sites. The structural regulation at two length scales leads to synchronous control over both the kinetics and thermodynamics for ORR on bimetallic ZIF catalysts. The optimized ZnCo-ZIF with a Zn/Co molar ratio of 9/1 and predominant {001} facet exposure exhibits a high 2e- selectivity of ∼100% and a H2O2 yield of 4.35 mol gcat-1 h-1. The findings pave a new avenue toward the development of multivariate MOFs as advanced 2e-ORR electrocatalysts.

5.
Neurobiol Dis ; 184: 106193, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37295561

RESUMEN

Dravet syndrome (DS) is a debilitating infantile epileptic encephalopathy characterized by seizures induced by high body temperature (hyperthermia), sudden unexpected death in epilepsy (SUDEP), cognitive impairment, and behavioral disturbances. The most common cause of DS is haploinsufficiency of the SCN1A gene, which encodes the voltage-gated sodium channel Nav1.1. In current mouse models of DS, the epileptic phenotype is strictly dependent on the genetic background and most mouse models exhibit drastically higher SUDEP rates than patients. Therefore, we sought to develop an alternative animal model for DS. Here, we report the generation and characterization of a Scn1a halploinsufficiency rat model of DS by disrupting the Scn1a allele. Scn1a+/- rats show reduced Scn1a expression in the cerebral cortex, hippocampus and thalamus. Homozygous null rats die prematurely. Heterozygous animals are highly susceptible to heat-induced seizures, the clinical hallmark of DS, but are otherwise normal in survival, growth, and behavior without seizure induction. Hyperthermia-induced seizures activate distinct sets of neurons in the hippocampus and hypothalamus in Scn1a+/- rats. Electroencephalogram (EEG) recordings in Scn1a+/- rats reveal characteristic ictal EEG with high amplitude bursts with significantly increased delta and theta power. After the initial hyperthermia-induced seizures, non-convulsive, and convulsive seizures occur spontaneously in Scn1a+/- rats. In conclusion, we generate a Scn1a haploinsufficiency rat model with phenotypes closely resembling DS, providing a unique platform for establishing therapies for DS.


Asunto(s)
Epilepsias Mioclónicas , Epilepsia , Convulsiones Febriles , Muerte Súbita e Inesperada en la Epilepsia , Ratones , Animales , Ratas , Canal de Sodio Activado por Voltaje NAV1.1/genética , Epilepsias Mioclónicas/genética , Convulsiones/genética , Neuronas/metabolismo , Fiebre/complicaciones , Fiebre/genética , Modelos Animales de Enfermedad
6.
Small ; 19(29): e2300292, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37029700

RESUMEN

Photocatalytic oxygen reduction reaction (ORR) for H2 O2 production in the absence of sacrificing agents is a green approach and of great significance, where the design of photocatalysts with high performance is the central task. Herein, a spatial specific S-scheme heterojunction design by introducing a novel semiconducting pair with a S-scheme mechanism in a purpose-designed Janus core-shell-structured hollow morphology is reported. In this design, TiO2 nanocrystals are grown inside the inner wall of resorcinol-formaldehyde (RF) resin hollow nanocakes with a reverse bumpy ball morphology (TiO2 @RF). The S-scheme heterojunction preserves the high redox ability of the TiO2 and RF pair, the spatial specific Janus design enhances the charge separation, promotes active site exposure, and reduces the H2 O2 decomposition to a large extent. The TiO2 @RF photocatalyst shows a high H2 O2 yield of 66.6 mM g-1  h-1 and solar-to-chemical conversion efficiency of 1.11%, superior to another Janus structure (RF@TiO2 ) with the same heterojunction but a reversed Janus spatial arrangement, and most reported photocatalysts under similar reaction conditions. The work has paved the way toward the design of next-generation photocatalysts for green synthesis of H2 O2 production.

7.
Am J Gastroenterol ; 117(12): 1982-1989, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36455222

RESUMEN

INTRODUCTION: Although recent guidelines recommend endoscopic resection of rectal neuroendocrine tumors (NET) ≤10 mm, there is no consensus on which endoscopic modality should be performed. We aimed to compare the safety and efficacy of modified cap-assisted endoscopic mucosal resection (mEMR-C) and endoscopic submucosal dissection (ESD) methods for the treatment of rectal NET ≤10 mm. METHODS: A randomized noninferiority trial comparing mEMR-C and ESD was conducted. The primary outcome was the histological complete resection rate; the secondary outcomes included en bloc resection rate, operation time, complications, and so on. Subgroup analyses and follow-up were also performed. RESULTS: Ninety patients were enrolled, and 79 patients with pathologically confirmed rectal NET were finally analyzed, including 38 cases of mEMR-C and 41 cases of ESD. Histological complete resection rate was 97.4% in the mEMR-C group and 92.7% in the ESD group. The noninferiority of mEMR-C compared with that of ESD was confirmed because the absolute difference was 4.7% (2-sided 90% confidence interval, -3.3% to 12.2%; P = 0.616). En bloc resection and successful removal of rectal NET were achieved in all patients. Advantages of mEMR-C over ESD included shorter operation time (8.89 ± 4.58 vs 24.8 ± 9.14 minutes, P < 0.05) and lower hospitalization cost ($2,233.76 ± $717.70 vs $2,987.27 ± $871.81, P < 0.05). Postoperative complications were recorded in 4 patients who received mEMR-C and 2 patients in the ESD group (11.5% vs 4.9%, P = 0.509), which were all well managed using endoscopy. Similar findings were observed when subgroup analysis was performed. DISCUSSION: mEMR-C is noninferior to ESD with a similar complete resection rate. In addition, mEMR-C had shorter procedure duration time and lower hospitalization costs. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03982264.


Asunto(s)
Resección Endoscópica de la Mucosa , Tumores Neuroendocrinos , Neoplasias del Recto , Humanos , Tumores Neuroendocrinos/cirugía , Neoplasias del Recto/cirugía , Tempo Operativo , Complicaciones Posoperatorias/epidemiología
8.
Environ Res ; 206: 112290, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-34717949

RESUMEN

Electrochemical two-electron water oxidation reaction (2e-WOR) provides a promising alternative route for hydrogen peroxide (H2O2) production, where the design of earth abundant and environmentally friendly electrocatalysts with both high selectivity and production rate is crucial. Here we report the synthesis of ZnO nanoparticles embedded in hollow carbon fiber membrane as efficient 2e-WOR electrocatalyst by a metal-organic framework engaged electrospinning-pyrolysis method. The resultant ZnO@carbon composite fiber exhibits a foam-like hierarchical structure composed of interconnected hollow carbon nanocubes encapsulated with oxygen vacancy rich ZnO nanocrystals. Owing to the improved selectivity of ZnO, excellent conductivity of carbon fiber, promoted active site exposure and mass transfer of hollow structure, the free-standing membrane electrode shows superior 2e-WOR performances with high selectivity (83.8% at 2.8 V vs. RHE), H2O2 generation rate (19.7 µmol cm-2 min-1) and robust stability.


Asunto(s)
Carbono , Óxido de Zinc , Carbono/química , Fibra de Carbono , Electrones , Peróxido de Hidrógeno , Agua , Óxido de Zinc/química
9.
Eat Weight Disord ; 27(7): 2561-2568, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35459986

RESUMEN

BACKGROUND: Studies have shown that the reference equations for the six-minute walking distance (6MWD), which were mainly derived from healthy, normal-weight people, are not suitable for individuals with obesity. The main purpose of this study was to establish reference equations for the 6MWD in obese Chinese subjects. METHODS: In our study, a total of 214 individuals with obesity performed the six-minute walking tests (6MWTs) according to the American thoracic society (ATS) guidelines, and the longer 6MWD was used for further analysis. The reference equations for the 6MWD were developed using stepwise multiple regression analysis. The newly established equations for the 6MWD were compared to the existing prediction equations. RESULTS: The mean 6MWD for the cohort was 523 ± 56 m. We found that the reliability of two 6MWTs was good. Age and BMI were identified as independent factors, and explained 31% and 27% of the variance in the 6MWD for the male and female participants, respectively. Thus, the reference equations reported in the previous studies did not accurately predict the 6MWD in our subjects. CONCLUSION: Our study was the first to describe the 6MWD in obese Chinese subjects and to propose new predictive equations. These established equations can improve the assessment of the health of obese Chinese patients whose exercise capacity is affected by the disease. LEVEL OF EVIDENCE: III, Cohort study.


Asunto(s)
Obesidad , Caminata , Adulto , China , Estudios de Cohortes , Femenino , Humanos , Masculino , Valores de Referencia , Reproducibilidad de los Resultados
10.
Angew Chem Int Ed Engl ; 61(44): e202209433, 2022 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-35965238

RESUMEN

Anisotropy plays a unique role in the structural regulation of metal-organic frameworks (MOFs) and their composites, especially at the micro- and nanoscale. However, there is a lack of a understanding of MOF micro/nanoparticles (MNPs) from the perspective of morphological anisotropy. In this Minireview, recent advances in anisotropic MOF MNPs are summarized, with a focus on how morphological anisotropy leads to innovative structures and modulates properties. First, anisotropic pristine MOF MNPs with diverse morphologies are introduced and classified by their morphology-dependent and morphology-independent anisotropy. Secondly, the anisotropy-enabled site-selective higher-order construction of MOF-based materials is highlighted. Finally, challenges and prospects for anisotropic MOFs are discussed, aiming to provide inspiration for further developments in this interesting research field.


Asunto(s)
Estructuras Metalorgánicas , Nanopartículas , Nanoestructuras , Estructuras Metalorgánicas/química , Anisotropía , Nanoestructuras/química , Nanopartículas/química
11.
J Immunol ; 202(6): 1704-1714, 2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30710045

RESUMEN

Glycine is a simple nonessential amino acid known to have neuroprotective properties. Treatment with glycine results in reduced infarct volume of the brain, neurologic function scores, and neuronal and microglial death in ischemic stroke injury. Neuroinflammation has been considered a major contributor to cerebral ischemia-induced brain damage. However, the role of glycine in neuroinflammation following ischemic stroke is unclear. The present study aimed to determine whether neuroinflammation is involved in the neuroprotective effects of glycine in cerebral ischemia injury. Ischemic stroke promotes M1 microglial polarization. Interestingly, we found that the injection of glycine in rats after injury can inhibit ischemia-induced inflammation and promote M2 microglial polarization in vivo (Sprague-Dawley rats) and in vitro (cortical microglia and BV-2 cells). We show that glycine suppresses Hif-1α by inhibiting the upregulation of NF-κB p65 after ischemia-reperfusion injury, resulting in the inhibition of proinflammatory activity. The activation of AKT mediates the inhibition of NF-κB p65/Hif-1α signaling by glycine. Moreover, we confirm that glycine-regulated AKT activation is mediated by the inhibition of PTEN in a PTEN depletion cell line, U251 cells. Glycine modulates microglial polarization after ischemic stroke, which indirectly inhibits ischemia-induced neuronal death and functional recovery. Taken together, our findings provide a new understanding of glycine in neuroprotection by inhibiting M1 microglial polarization and promoting anti-inflammation by suppressing NF-κB p65/Hif-1α signaling.


Asunto(s)
Encéfalo/efectos de los fármacos , Glicina/farmacología , Microglía/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Accidente Cerebrovascular/inmunología , Animales , Encéfalo/inmunología , Encéfalo/patología , Isquemia Encefálica/inmunología , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Femenino , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Accidente Cerebrovascular/metabolismo , Accidente Cerebrovascular/patología , Factor de Transcripción ReIA/metabolismo
12.
Neurochem Res ; 45(8): 1769-1780, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32415405

RESUMEN

The mechanism of cognitive dysfunction in diabetes is still unclear. Recently, studies have shown that the cerebellum is involved in cognition. Furthermore, diabetes-induced cerebellar alterations is related to vascular changes. Therefore, we aimed to explore the roles of vascular function in diabetes-induced cerebellar damage and motor learning deficits. Type 1 diabetes was induced by a single injection of streptozotocin in Sprague-Dawley rats. Motor learning was assessed by beam walk test and beam balance test. The pathological changes of the cerebellum were assessed by Hematoxylin and eosin staining and Nissl staining. Apoptosis was evaluated by anti-caspase-3 immunostaining. Protein expression was evaluated by western blotting and double immunofluorescence. Our results have shown that motor learning was impaired in diabetic rats, coupled with damaged Purkinje cells and decreased capillary density in the cerebellum. In addition, the protein expression of neuronal NOS, inducible NOS, endothelial NOS, total nitric oxide, vascular endothelial growth factor and its cognate receptor Flk-1 was decreased in the cerebellum. Gastrodin treatment ameliorated neuronal damage and restored protein expression of relevant factors. Arising from the above, it is suggested that vascular dysfunction and NO signaling deficits in the cerebellum may be the underlying mechanism of early manifestations of cognitive impairment in diabetes, which could be ameliorated by gastrodin intervention.


Asunto(s)
Conducta Animal/efectos de los fármacos , Alcoholes Bencílicos/uso terapéutico , Disfunción Cognitiva/tratamiento farmacológico , Glucósidos/uso terapéutico , Locomoción/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Corteza Cerebelosa/efectos de los fármacos , Corteza Cerebelosa/enzimología , Corteza Cerebelosa/patología , Disfunción Cognitiva/epidemiología , Diabetes Mellitus Experimental/complicaciones , Endotelio Vascular/efectos de los fármacos , Masculino , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa/metabolismo , Células de Purkinje/efectos de los fármacos , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
13.
BMC Pulm Med ; 20(1): 177, 2020 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-32571358

RESUMEN

BACKGROUND: The six-minute walking test (6MWT) is a tool that plays a key role in evaluating the functional exercise capacity, prognosis and evaluation of treatment response of patients with various cardiopulmonary diseases. However, standard reference equations are currently unavailable for the six-minute walking distance (6MWD) for people aged 60-85 years in China. The purpose of this study was to 1) measure the 6MWD of healthy Chinese people aged 60-85 years, 2) establish reference equations for predicting the 6MWD, and 3) compare our reference equations with equations reported in previously published studies. METHOD: We obtained informed consent from each participant prior to the test, and the research design was approved by the Ethics Committee of Wenzhou People's Hospital. The demographic and anthropometric data and the 6MWD of healthy Chinese subjects aged 60-85 years old were measured using a standardized protocol. Every subject completed two 6MWTs, and the longest 6MWD further analyzed. RESULTS: Two hundred sixty-six subjects (128 males and 138 females) completed the 6MWT, and the mean walking distance was 518 ± 72 m. Males achieved a longer walking distance than females (518 ± 72 m vs. 487 ± 70 m; p < 0.0001), and active subjects achieved a longer walking distance than nonactive subjects (512 ± 76 m vs. 485 ± 63 m; p < 0.0001). According to the univariate analysis, the 6MWD was significantly associated with age, height, body mass index (BMI), heart rate and blood pressure after exercise and changes in heart rate before and after exercise. The stepwise multivariate regression analysis identified age, height and BMI as independent predictors of the 6MWD. The reference equations for Caucasians and South Americans tended to overestimate the 6MWD of our subjects, while the equations for Asian and African populations tended to underestimate the 6MWD. CONCLUSIONS: This study is the first to describe the 6MWD of healthy Chinese people aged 60-85 years, and reference prediction equations were proposed. These findings will help to improve the evaluation of Chinese patients with diseases that affect exercise capacity.


Asunto(s)
Pueblo Asiatico , Frecuencia Cardíaca , Prueba de Paso , Caminata , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Peso Corporal , China , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Análisis de Regresión
14.
Neurochem Res ; 44(4): 978-993, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30747310

RESUMEN

Cognitive impairment in diabetes (CID) is a severe chronic complication of diabetes mellitus (DM). It has been hypothesized that diabetes can lead to cognitive dysfunction due to expression changes of excitatory neurotransmission mediated by N-methyl-D-aspartate receptors (NMDAR) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR); however, the pathogenesis involved in this has not been fully understood, especially at early phase of DM. Here, we sought to determine the cognitive changes and aim to correlate this with the expression changes of NMDAR and AMPAR of glutamate signaling pathways in the rat hippocampus from early phase of DM and in the course of the disease progression. By Western blot analysis and immunofluorescence labeling, the hippocampus in diabetic rats showed a significant increase in protein expression NMDAR subunits NR1, NR2A and NR2B and AMPAR subunit GluR1. Along with this, behavioral test by Morris water maze showed a significant decline in their performance when compared with the control rats. It is suggested that NR1, NR2A, NR2B and GluR1are involved in learning and memory and that their expression alterations maybe correlated with the occurrence and development of CID in diabetic rats induced by streptozotocin.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Hipocampo/metabolismo , Trastornos de la Memoria/metabolismo , Receptores AMPA/biosíntesis , Receptores de N-Metil-D-Aspartato/biosíntesis , Animales , Diabetes Mellitus Experimental/patología , Expresión Génica , Hipocampo/patología , Masculino , Aprendizaje por Laberinto/fisiología , Trastornos de la Memoria/patología , Subunidades de Proteína/biosíntesis , Subunidades de Proteína/genética , Ratas , Ratas Sprague-Dawley , Receptores AMPA/genética , Receptores de N-Metil-D-Aspartato/genética
15.
Glycoconj J ; 35(3): 287-297, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29671117

RESUMEN

Dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) is an important C-type lectin and plays a critical role in the recognition of pathogens and self-antigens. It has recently been shown that DC-SIGN directly interacts with acute T lymphoblastic leukemia cells. However, the mechanism regulating DC-SIGN-dependent DC association as well as related functions is still elusive. Here we showed that DC-SIGN preferentially bound to a set of malignant T lymphocytes, including Jurkat, CCRF-HSB2 and CCRF-CEM. ICAM-2/3 on Jurkat cells appeared to be the responsible ligands and the block of ICAM-2/3 dramatically impaired DC-SIGN association. We also found that ICAM-2/3 bear a considerable amount of Lewis X, Lewis Y and Lewis A residues, which are important for DC-SIGN recognition. Furthermore, transcriptome analysis revealed an upregulation of fucosyltransferase 4 (FUT4) in Jurkat cells and downregulating FUT4 limited DC-SIGN binding, indicating a previously unappreciated role of FUT4 in the control of Lewis antigens on malignant T lymphocytes. In addition, the presence of Jurkat cells impaired DC maturation and the block of DC-SIGN improved Jurkat cell-mediated effects on DC function and T cell differentiation. Together, we provide evidence that DC-SIGN orients DC association with acute T lymphoblastic leukemia cells and orchestrates DC functions.


Asunto(s)
Antígenos CD/metabolismo , Moléculas de Adhesión Celular/metabolismo , Células Dendríticas/metabolismo , Lectinas Tipo C/metabolismo , Leucemia de Células T/metabolismo , Antígenos del Grupo Sanguíneo de Lewis/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores de Superficie Celular/metabolismo , Células Dendríticas/patología , Fucosiltransferasas/metabolismo , Humanos , Células Jurkat , Leucemia de Células T/patología , Antígeno Lewis X/metabolismo
16.
Acta Biochim Biophys Sin (Shanghai) ; 50(6): 567-578, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29718150

RESUMEN

Hypopharyngeal carcinoma (HC) is one of the most malignant tumors in the upper aerodigestive tract. Currently, there are no effective treatments for HC. Gold nanoparticles (AuNPs) are a promising tool that can be used for plasmonic photothermal therapy (PPTT), which refers to the use of electromagnetic radiation, most often in near infrared (NIR) region, for the treatment of various medical conditions including cancer. AuNPs have been proved to be a promising tool for NIR spectroscopy-mediated photothermal therapies. In this study, we chemically conjugated AuNPs with a monoclonal antibody (mAb) targeting the epidermal growth factor receptor (EGFR), a cell-surface receptor that is overexpressed in many cancers. We then assessed the effect of NIR photothermal treatment with the EGFRmAb-AuNPs in FaDu HC cells. Our data showed that nanoparticle conjugation with the EGFRmAb improved the specific targeting towards FaDu cells and reduced cytotoxicity towards normal (293 T) cells which do not overexpress the EGFR. A significant amount of our EGFRmAb-conjugated AuNPs could enter the nucleus. Moreover, the expression levels of double strand DNA break repair proteins, including p-ATR, p-CHK1, and p-CHK2 were increased following AuNPs treatment, indicating the presence of DNA damage. These findings suggest that the AuNPs can potentially disrupt genome integrity and induce apoptosis. In addition, EGFRmAb-AuNPs+NIR could induce FaDu cell apoptosis, accompanied by the inhibition of the PI3K/AKT/mTOR pathway and stimulation of DNA damage response. Based on these data, PPTT using the EGFRmAb-AuNPs could be a new promising treatment for HC.


Asunto(s)
Apoptosis/efectos de los fármacos , Daño del ADN , Inmunoconjugados/farmacología , Fosfotransferasas/metabolismo , Transducción de Señal/efectos de los fármacos , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/inmunología , Apoptosis/efectos de la radiación , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Supervivencia Celular/efectos de la radiación , Receptores ErbB/inmunología , Oro/química , Células HEK293 , Humanos , Neoplasias Hipofaríngeas/genética , Neoplasias Hipofaríngeas/metabolismo , Neoplasias Hipofaríngeas/patología , Inmunoconjugados/química , Inmunoconjugados/inmunología , Rayos Infrarrojos , Nanopartículas del Metal/química , Fosfatidilinositol 3-Quinasas/metabolismo , Fototerapia/métodos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/genética , Transducción de Señal/efectos de la radiación , Serina-Treonina Quinasas TOR/metabolismo
17.
Surg Endosc ; 31(8): 3234-3241, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-27864723

RESUMEN

BACKGROUND: Peroral endoscopic myotomy (POEM) is a novel treatment for achalasia with excellent outcomes. But the predictor for treatment failure is not well defined. This study was aimed to prospectively investigate the factors for predicting failed POEM. METHODS: From June 2011 to May 2015, a total of 115 achalasia patients treated by POEM were included for the retrospective cohort study from Nanfang Hospital and the First People's Hospital of Yunnan Province. Patients were followed up with Eckardt score, high-resolution manometry and endoscope. POEM failure was defined as primary failure (Eckardt score failed to decrease to 3 or below) and recurrences (decrease of Eckardt score to 3 or below, then rise to more than 3) during one-year follow-up. Univariate and multivariate Cox regression analyses were performed to assess the predictive factor. For the associated factor, receiver operating characteristic curve (ROC) was utilized to determine the cutoff value of the predicting factor. RESULTS: The failure rate of POEM after 1 year was 7.0% (8/115), including 5 primary failure cases and 3 recurrences. Multivariate analysis showed higher pre-treatment Eckardt score was the single independent factor associated with POEM failure [9.5 (6-12) vs. 7 (2-12), odds ratio (OR) 2.24, 95 confidence interval (95% CI) 1.39-3.93, p = 0.001]. The cutoff value (Eckardt score ≥9) had 87.5 sensitivity (95% CI 47.3-99.7%) and 73.8% specificity (95% CI 64.4-81.9%) for predicting failed POEM. CONCLUSIONS: Pre-treatment Eckardt score could be a predictive factor for failed POEM. Eckardt score ≥9 was associated with high sensitivity and specificity for predicting POEM failure.


Asunto(s)
Acalasia del Esófago/cirugía , Índice de Severidad de la Enfermedad , Adulto , China , Bases de Datos Factuales , Acalasia del Esófago/mortalidad , Esfínter Esofágico Inferior/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Miotomía/métodos , Cirugía Endoscópica por Orificios Naturales/métodos , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
18.
Med Sci Monit ; 22: 3113-23, 2016 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-27587310

RESUMEN

BACKGROUND Transplantation with allogeneic cells has become a promising modality for cancer therapy, which can induce graft-versus-tumor (GVT) effect. This study was aimed at assessing the safety, efficacy, and tissue type GVT (tGVT) response of transplantation with allogeneic skin tumors to treat chemically-induced skin tumors in mice. MATERIAL AND METHODS FVB/N and ICR mice were exposed topically to chemicals to induce skin tumors. Healthy ICR mice were transplanted with allogeneic skin tumors from FVB/N mice to test the safety. The tumor-bearing ICR mice were transplanted with, or without, allogeneic skin tumors to test the efficacy. The body weights (BW), body condition scores (BCS), tumor volumes in situ, metastasis tumors, overall survival, and serum cytokines were measured longitudinally. RESULTS Transplantation with no more than 0.03 g allogeneic skin tumors from FVB/N mice to healthy ICR mice was safe. After transplantation with allogeneic skin tumors to treat tumor-bearing mice, it inhibited the growth of tumors slightly at early stage, accompanied by fewer metastatic tumors at 24 days after transplantation (21.05% vs. 47.37%), while there were no statistically significant differences in the values of BW, BCS, tumor volumes in situ, metastasis tumors, and overall survival between the transplanted and non-transplanted groups. The levels of serum interleukin (IL)-2 were significantly reduced in the controls (P<0.05), but not in the recipients, which may be associated with the tGVT response. CONCLUSIONS Our results suggest that transplantation with allogeneic skin tumors is a safe treatment in mice, which can induce short-term tGVT response mediated by IL-2.


Asunto(s)
Efecto Injerto vs Tumor/inmunología , Trasplante de Neoplasias/inmunología , Trasplante de Neoplasias/métodos , Neoplasias Cutáneas/inmunología , Neoplasias Cutáneas/terapia , Animales , Carcinoma de Células Escamosas/inmunología , Carcinoma de Células Escamosas/terapia , Femenino , Interleucina-2/metabolismo , Ratones , Ratones Endogámicos ICR , Distribución Aleatoria , Trasplante Homólogo/métodos
19.
Cell Mol Biol Lett ; 20(5): 816-24, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26556846

RESUMEN

Macrophage galactose-type lectin (MGL) participates in the regulation of T cell apoptosis, but the exact death pathway remains unclear. Here, we demonstrated that MGL-induced T cell death occurs in a caspase-independent manner. Furthermore, MGL treatment triggers the translocation of endonuclease G (EndoG) and apoptosis-inducing factor (AIF) from the mitochondria to the nucleus. Because galectin-1 (Gal-1) can also initiate similar mitochondrial events, we speculate that this death pathway may be widely used by the lectin family.


Asunto(s)
Factor Inductor de la Apoptosis/metabolismo , Apoptosis , Endodesoxirribonucleasas/metabolismo , Lectinas Tipo C/metabolismo , Linfocitos T/metabolismo , Caspasas/metabolismo , Línea Celular Tumoral , Núcleo Celular/metabolismo , Humanos , Células Jurkat , Lectinas Tipo C/genética , Microscopía Fluorescente , Mitocondrias/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/inmunología
20.
J Neuroinflammation ; 11: 176, 2014 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-25297558

RESUMEN

BACKGROUND: The damaging effect of combustion smoke inhalation on the lung is widely reported but information on its effects on the olfactory bulb is lacking. This study sought to determine the effects of smoke inhalation on the olfactory bulb, whose afferent input neurons in the nasal mucosa are directly exposed to external stimuli, such as smoke. METHODS: Adult male Sprague-Dawley rats were subjected to combustion smoke inhalation and sacrificed at different time points. Changes in olfactory bulb proteins including vascular endothelial growth factor (VEGF), inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (eNOS), neuronal nitric oxide synthase (nNOS), Na+-K+-Cl- cotransporter 1 (NKCC1), glial fibrillary acidic protein (GFAP), and aquaporin-4 (AQP4) were evaluated by Western blot analysis. In addition, ELISA was conducted for cytokine and chemokine levels, and double immunofluorescence labeling was carried out for GFAP/VEGF, GFAP/AQP4, NeuN/nNOS, GFAP/NKCC1, NeuN/NKCC1, GFAP/Rhodamine isothiocyanate (RITC), and transferase dUTP nick end labeling (TUNEL). Aminoguanidine was administered to determine the effects of iNOS inhibition on the targets probed after smoke inhalation. RESULTS: The results showed a significant increase in VEGF, iNOS, eNOS, nNOS, NKCC1, and GFAP expression in the bulb tissues, with corresponding increases in inflammatory cytokines and chemokines after smoke inhalation. Concurrent to this was a drastic increase in AQP4 expression and RITC permeability. Aminoguanidine administration decreased the expression of iNOS and RITC extravasation after smoke inhalation. This was coupled with a significant reduction in incidence of TUNEL + cells that was not altered with administration of L-NG-nitroarginine methyl ester (L-NAME). CONCLUSIONS: These findings suggest that the upregulation of iNOS in response to smoke inhalation plays a major role in the olfactory bulb inflammatory pathophysiology, along with a concomitant increase in pro-inflammatory molecules, vascular permeability, and edema. Overall, these findings indicate that the olfactory bulb is vulnerable to smoke inhalation.


Asunto(s)
Inflamación/patología , Bulbo Olfatorio/patología , Humo/efectos adversos , Animales , Apoptosis , Western Blotting , Citocinas/análisis , Técnica del Anticuerpo Fluorescente , Inflamación/metabolismo , Masculino , Bulbo Olfatorio/metabolismo , Ratas , Ratas Sprague-Dawley
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