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1.
J Cell Mol Med ; 28(6): e18223, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38451046

RESUMEN

Hepatoblastoma (HB), a primary liver tumour, is notorious for its high metastatic potential and poor prognosis. Ganoderma lucidum, an edible mushroom species utilized in traditional Chinese medicine for addressing various tumour types, presents an intriguing avenue for HB treatment. However, the effectiveness of G. lucidum in managing HB and its underlying molecular mechanism necessitates further exploration. Standard in vitro assays were conducted to evaluate the impact of sporoderm-broken spores of G. lucidum (SBSGL) on the malignant characteristics of HB cells. The mechanism of SBSGL in treating HB and its tumour immunomodulatory effects were explored and validated by various experiments, including immunoprecipitation, Western blotting, mRFP-GFP-LC3 adenovirus transfection and co-localization analysis, as well as verified with in vivo experiments in this regard. The results showed that SBSGL effectively inhibited the malignant traits of HB cells and suppressed the O-GlcNAcylation of RACK1, thereby reducing its expression. In addition, SBSGL inhibited immune checkpoints and regulated cytokines. In conclusion, SBSGL had immunomodulatory effects and regulated the malignancy and autophagy of HB by regulating the O-GlcNAcylation of RACK1. These findings suggest that SBSGL holds promise as a potential anticancer drug for HB treatment.


Asunto(s)
Hepatoblastoma , Neoplasias Hepáticas , Reishi , Hepatoblastoma/tratamiento farmacológico , Hepatoblastoma/genética , Esporas Fúngicas , Autofagia , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética
2.
Clin Chem Lab Med ; 62(3): 472-483, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-37843302

RESUMEN

OBJECTIVES: To develop a sensitive point-of-care testing (POCT) aqueous vascular endothelial growth factor (VEGF) detection system, and assess its role for predicting the response to anti-VEGF treatment in macular edema secondary to retinal vein occlusion (RVO-ME) patients. METHODS: An automatic point-of-care aqueous humor Magnetic Particle Chemiluminescence Enzyme Immuno-Assay (MPCLEIA) VEGF detection system was developed. The predictive values of aqueous cytokine levels, in combination with imaging parameters, on anatomical treatment response (ATR, the relative central macular thickness change [ΔCMT/bl-CMT]) were analyzed. RESULTS: The automatic MPCLEIA system was able to provide results in 45 min with only 20 µL sample. Among the 57 eyes with available pre- and post-treatment evaluation, ATR significantly correlated with levels of interleukin (IL)-6, IL-8, monocyte chemoattractant protein-1 (MCP-1) and VEGF measured by Luminex xMAP platform, and VEGF measured by MPCLEIA. Optimal cut-off values for these biomarkers were 13.26 ng/L, 23.57 ng/L, 1,110.12 ng/L, 105.52 ng/L, and 85.39 ng/L, respectively. Univariate analysis showed significant associations between ATR category (good response if ATR≤-25 % or poor response otherwise) and IL-6, IL-8, MCP-1, VEGF-xMAP, and VEGF-MPCLEIA (p<0.05). Multivariate logistic regression revealed that ATR category was significantly associated with aqueous VEGF-MPCLEIA (p=0.006) and baseline(bl)-CMT (p=0.008). Receiver operating characteristics analysis yielded an AUC of 0.959 for the regression model combining VEGF-MPCLEIA and bl-CMT, for predicting ATR category. CONCLUSIONS: Our novel MPCLEIA-based automatic VEGF detection system enables accurate POCT of aqueous VEGF, which shows promise in predicting the treatment response of RVO-ME to anti-VEGF agents when combined with bl-CMT.


Asunto(s)
Edema Macular , Factor A de Crecimiento Endotelial Vascular , Humanos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Sistemas de Atención de Punto , Interleucina-8 , Edema Macular/diagnóstico , Edema Macular/metabolismo , Factores de Crecimiento Endotelial Vascular/metabolismo , Interleucina-6 , Humor Acuoso/metabolismo
3.
Neuropathol Appl Neurobiol ; 49(5): e12934, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37705167

RESUMEN

BACKGROUND AND PURPOSE: Hyperphosphorylation of Tau is one of the important pathological features of Alzheimer's disease (AD). Therefore, studying the mechanisms behind Tau hyperphosphorylation is crucial in exploring the pathogenesis of neurological damage in AD. METHODS: In this study, after the establishment of rat models of AD, quantitative phosphoproteomics and proteomics were performed to identify proteins, showing that phosphorylation of microtubule associated protein 1A (MAP 1A) was lower in the model group. Western blot confirmed the changes of MAP 1A in the SD rats, APP/PS1 transgenic mice and cell AD models. To further study the molecular mechanism of recombinant MAP 1A phosphorylation affecting Tau phosphorylation, interfering siRNA-MAP 1A and protein immunoprecipitation reaction analysis were performed in AD cell models. RESULTS: Cyclin-dependent kinase 5 (CDK5) showed reduced binding to MAP 1A and increased binding to Tau, resulting in a decrease in phosphorylated MAP 1A (p-MAP 1A) and an increase in phosphorylated Tau (p-Tau), and MAP 1A silencing promoted binding of CDK5-Tau and increased Tau phosphorylation, thereby reducing the cell survival rate. CONCLUSIONS: In summary, we found that p-MAP 1A downregulation associated with p-Tau upregulation was due to their altered binding forces to CDK5, and MAP 1A could enhance autophosphorylation by competitive binding to CDK5 and antagonise Tau phosphorylation. This leads to neuronal protection and reducing tissue damage levels in AD, which can help better understand the mechanisms of AD pathogenesis.


Asunto(s)
Enfermedad de Alzheimer , Animales , Ratones , Ratas , Enfermedad de Alzheimer/metabolismo , Ratones Transgénicos , Fosforilación , Ratas Sprague-Dawley , Proteínas tau/metabolismo , Regulación hacia Arriba
4.
Mol Cell Biochem ; 478(12): 2657-2669, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36899139

RESUMEN

Epitranscriptomics, also known as "RNA epigenetics", is a type of chemical modification that regulates RNA. RNA methylation is a significant discovery after DNA and histone methylation. The dynamic reversible process of m6A involves methyltransferases (writers), m6A binding proteins (readers), as well as demethylases (erasers). We summarized the current research status of m6A RNA methylation in the neural stem cells' growth, synaptic and axonal function, brain development, learning and memory, neurodegenerative diseases, and glioblastoma. This review aims to provide a theoretical basis for studying the mechanism of m6A methylation and finding its potential therapeutic targets in nervous system diseases.


Asunto(s)
Metiltransferasas , ARN , Metilación , ARN/metabolismo , Metiltransferasas/metabolismo , Sistema Nervioso/metabolismo
5.
Biomarkers ; 28(6): 531-537, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37352111

RESUMEN

INTRODUCTION: Contact lens discomfort (CLD) acts as a challenging problem, and the associated conjunctival microbiome changes were unclear. MATERIAL AND METHODS: Conjunctival sac swab samples were collected from 12 eyes of nonwearers (NW), 12 eyes of asymptomatic contact lens (ACL) wearers, and 11 eyes of CLD. The V3-V4 region of the 16S rRNA gene sequencing was used to investigate differences among three groups. RESULTS: No differences in alpha diversity were observed among the three groups. The beta diversity showed a distinct microbiome composition between ACL and CLD group (P = 0.018) with principal coordinate analysis. The relative abundance of Firmicutes was significantly higher in CLD (48.18%) than in ACL (13.21%) group (P = 0.018). The abundance of Bacillus in patients with ACL (0.05%) or with CLD (0.02%) were significantly lower than that in the NW (1.27%) group (P = 0.024, 0.028, respectively). Moreover, the abundance of Firmicutes was positively correlated with the OSDI scores in CLD patients (r = 0.817, P < 0. 01, Spearman). DISCUSSIONS: Patients with CLD have various degrees of bacterial microbiota imbalance in the conjunctival sac, compared with NW and ACL groups. CONCLUSION: Firmicutes may serve as a potential biomarker for the CLD patients.


In the current study, we investigated the conjunctival microbiome changes among nonwearers (NW), asymptomatic contact lens (ACL) wearers, and contact lens discomfort (CLD) patients using high-throughput 16S rRNA gene sequencing, and correlated relative abundances of the microbiota with clinical parameters.The relative abundance of Firmicutes was higher in CLD than that in ACL group. The abundance of Bacillus was lower in ACL or CLD group than that in NW group. The abundance of Firmicutes was positively correlated with the OSDI scores in CLD patients.Firmicutes may serve as a potential biomarker for the CLD patients.


Asunto(s)
Lentes de Contacto Hidrofílicos , Microbiota , Humanos , ARN Ribosómico 16S/genética , Conjuntiva/microbiología , Lentes de Contacto Hidrofílicos/efectos adversos , Lentes de Contacto Hidrofílicos/microbiología , Bacterias/genética , Microbiota/genética
6.
Int J Med Sci ; 20(7): 870-887, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37324188

RESUMEN

Background: Hepatocellular carcinoma is a rapidly advancing malignancy with a poor prognosis. Therefore, further research is needed on its potential pathogenesis and therapeutic targets. Methods: In this study, the relevant datasets were downloaded from the TCGA database and the key modules were identified using WGCNA in the necroptosis-related gene set, while single-cell datasets were scored using the necroptosis gene set. Differential genes in the high- and low-expression groups were determined using the WGCNA module genes as intersection sets to identify key genes involved in necroptosis in liver cancer. Then, prognostic models were constructed using LASSO COX regression followed by multi-faceted validation. Finally, model genes were found to be correlated with key proteins of the necroptosis pathway and used to identify the most relevant genes, followed by their experimental validation. Subsequently, on the basis of the analysis results, the most relevant SFPQ was selected for cell-level verification. Results: We constructed a prognosis model that included five necroptosis-related genes (EHD1, RAC1, SFPQ, DAB2 and PABPC4) to predict the prognosis and survival of HCC patients. The results showed that the prognosis was more unfavorable in the high-risk group compared to the low-risk group, which was corroborated using ROC curves and risk factor plots. In addition, we further checked the differential genes using GO and KEGG analyses and found that they were predominantly enriched in the neuroactive ligand-receptor interaction pathway. The results of the GSVA analysis demonstrated that the high-risk group was mainly enriched in DNA replication, regulation of the mitotic cycle, and regulation of various cancer pathways, while the low-risk group was predominantly enriched in the metabolism of drugs and xenobiotics using cytochrome P450. SFPQ was found to be the main gene that affects the prognosis and SFPQ expression was positively correlated with the expression of RIPK1, RIPK3 and MLKL. Furthermore, the suppression of SFPQ could inhibit hyper-malignant phenotype HCC cells, while the WB results showed that inhibition of SFPQ expression also resulted in lower expression of necroptosis proteins, compared to the sh-NC group. Conclusions: Our prognostic model could accurately predict the prognosis of patients with HCC to further identify novel molecular candidates and interventions that can be used as alternative methods of treatment for HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Pronóstico , Bases de Datos Factuales , Necroptosis , Proteínas de Transporte Vesicular
7.
Pharmacol Res ; 184: 106420, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36049664

RESUMEN

Glycosylation is a critical post-translational modification (PTM) that affects the function of proteins and regulates cell signaling, thereby regulating various biological processes. Protein oxygen-N-acetylglucosamine (O-GlcNAc) glycosylation modifications are glycochemical modifications that occur within cells in the signal transduction and are frequently found in the cytoplasm and nucleus. Due to the rapid and reversible addition and removal, O-GlcNAc modifications are able to reversibly compete with certain phosphorylation modifications, immediately regulate the activity of proteins, and participate in kinds of cellular metabolic and signal transduction pathways, playing a pivotal role in the regulation of tumors, diabetes, and other diseases. This article provided a brief overview of O-GlcNAc glycosylation modification, introduced its role in altering the progression and immune response regulation of gastrointestinal tumors, and discussed its potential use as a marker of tumor neogenesis.


Asunto(s)
Acetilglucosamina , Neoplasias Gastrointestinales , Glicosilación , Humanos , N-Acetilglucosaminiltransferasas/metabolismo , Oxígeno/metabolismo , Procesamiento Proteico-Postraduccional
8.
Gynecol Endocrinol ; 38(11): 960-964, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36184827

RESUMEN

OBJECTIVE: To investigate the relationship between ovulation and pregnancy outcomes in patients undergoing intrauterine insemination (IUI). METHODS: The clinical data from 784 patients, diagnosed with polycystic ovarian syndrome (PCOS) or unexplained infertility, underwent 1624 IUI cycles were analyzed retrospectively. Ovulation was observed by transvaginal ultrasonography on the day of IUI. The clinical pregnancy rate (CPR), abortion rate (AR), and live birth rate (LBR) were analyzed. RESULTS: The study included 1031 pre-ovulation IUI cycles (63.49%) and 593 post-ovulation IUI cycles (36.51%). The CPR was 13.05%, the AR was 15.57%, and the LBR was 11.02%. Ovulation before or after IUI affected the CPR (11.06% VS 16.53%, p = .002) and LBR (9.41% VS 13.83%, p = .006) per cycle, but did not affect the AR (14.91% VS 16.33%, p = .149). The sex ratio of children was not related to ovulation (p = .948). After adjusting for baseline characteristics and logistic regression, the CPR (OR = 1.931, 95% CI 1.062-1.931, p = .019) and LBR (OR = 1.389, 95% CI 1.007-1.916, p = .045) of post-ovulation insemination were higher than those of pre-ovulation insemination significantly. CONCLUSION: Pregnancy outcomes were affected by ovulation on the day of IUI in patients with unexplained infertility or PCOS. Post-ovulation insemination may improve the CPR of IUI.


Asunto(s)
Infertilidad , Síndrome del Ovario Poliquístico , Femenino , Embarazo , Humanos , Resultado del Embarazo , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/terapia , Inseminación Artificial , Estudios Retrospectivos , Índice de Embarazo , Inducción de la Ovulación , Inseminación , Ovulación
9.
Int J Mol Sci ; 23(21)2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36361664

RESUMEN

Some traditional acidic ionic liquids (AILs) have shown great catalytic potential in esterification; meanwhile, the design and application of more new AILs are expected at present.Tropine-based functionalized acidic ionic liquids (FAILs) were synthesized to realize esterification catalysis for the first time; with aspirin synthesis as the template reaction, key influences on the substrate conversion and product yield of the synthesis, such as IL type, ratio of salicylic acid to acetic anhydride, temperature, reaction time and amount of IL, were investigated. The new tropine-based FAILs exhibited excellent performance in catalytic synthesis of aspirin with 88.7% yield and 90.8% selectivity. Multiple recovery and re-usage of N-(3-propanesulfonic acid) tropine is the cation, and p-toluenesulfonic acid is the anion. ([Trps][OTs]) shows satisfactory results. When [Trps][OTs] was used to catalyze different esterification reactions, it also showed good results. The above studies proved that ionic liquid [Trps][OTs] could serve as an ideal green solvent for esterification reaction, which serves as a suitable substitute for current catalysts.


Asunto(s)
Líquidos Iónicos , Ácidos , Aspirina , Catálisis , Esterificación
10.
Int J Mol Sci ; 23(20)2022 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-36293456

RESUMEN

Imidazolium-based ionic liquids are wildly used in natural product adsorption and purification. In this work, one typical polymeric ionic liquid (PIL) was synthesized by using L-proline as the anion, which exhibited excellent adsorption capacity toward tea polyphenol epigallocatechin gallate (EGCG). The adsorption conditions were optimized with the response surface method (RSM). Under the optimum conditions, the adsorption capacity of the PIL for EGCG can reach as high as 552 mg/g. Dynamics and isothermal research shows that the adsorption process of EGCG by the PIL particularly meets the quasi-second-order kinetic equation and monolayer adsorption mechanism. According to thermodynamic parameter analysis, the adsorption process is endothermic and spontaneous. The results of theoretical calculation by molecular docking also demonstrated the interaction mechanisms between EGCG and the ionic liquid. Considering the wide application of imidazolium-based ionic liquids in component adsorption and purification, the present study can not only be extended to other similar experimental mechanism validation, but also be representative for guiding the synthesis of PIL and optimization of adsorption conditions.


Asunto(s)
Productos Biológicos , Líquidos Iónicos , Polifenoles , Simulación del Acoplamiento Molecular , Polímeros , , Prolina
11.
Saudi Pharm J ; 30(11): 1561-1571, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36465852

RESUMEN

Objectives: Huangpu Tongqiao Capsule (HPTQC) is a traditional Chinese medicine (TCM) that has been used to treat Alzheimer's disease (AD). This study was to explore the pharmacological action and molecular mechanism of HPTQC in the treatment of AD. Methods: The possible targets of HTPQC were predicted by the molecular docking technique. Intraperitoneal injection of D-galactose and bilateral injection of Aß25-35 in hippocampus induced AD rat model. Morris water maze was used to observe learning and memory function. The primary hippocampal neurons were induced by Aß25-35. Moreover, the apoptosis rate of hippocampal nerve cells was detected through AnnexinV/PI double standard staining. The mRNA and protein levels of GRP78, CHOP, Caspase 12, Caspase 9, and Caspase 3 were detected by PCR and western blot. Results: The prediction results suggest that HPTQC may act on GRP78. HPTQC significantly improved the learning and memory function, and decreased neuronal apoptosis in vivo and in vitro. In addition, HPTQC could decrease the mRNA and protein expression levels of GRP78, CHOP, Caspase12, Caspase9, and Caspase3, and the effect trend was consistent with the specific inhibitor of GRP78. Conclusions: HPTQC has a neuroprotective effect against AD by inhibiting the apoptosis pathway mediated by endoplasmic reticulum stress.

12.
Angew Chem Int Ed Engl ; 60(38): 20872-20878, 2021 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-34254414

RESUMEN

Responsive molecular devices are one of the core units for molecular electronics, and dynamic covalent bonds (DCBs) provide the opportunity for the fabrication of responsive molecular devices. Herein we employ a single dynamic acyl hydrazone bond to fabricate tailored molecular devices using the scanning tunneling microscopy break-junction technique (STM-BJ) and the eutectic Ga-In technique (EGaIn). We found that the single-DCB-tailored molecular devices exhibited acid-base and/or photo-thermal response with three well-defined molecular conductance states. The reversible switching has the ON/OFF ratio of ≈10 between each state for single-molecule junctions and ≈3 for the SAMs-based molecular junctions. Combined with the density functional theory calculations, we revealed that the multiple conductance states of these molecular junctions originate from the dynamic acyl hydrazone bond exchange and C=N isomerization. Our work opens the avenue towards the design of tailored single-molecule electrical devices by implanting dynamic covalent bonds in molecular architectures.

13.
Med Res Rev ; 40(1): 27-53, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31070260

RESUMEN

Fluorescence imaging is a promising visualization tool and possesses the advantages of in situ response and facile operation; thus, it is widely exploited for bioassays. However, traditional fluorophores suffer from concentration limits because they are always quenched when they aggregate, which impedes applications, especially for trace analysis and real-time monitoring. Recently, novel molecules with aggregation-induced emission (AIE) characteristics were developed to solve the problems encountered when using traditional organic dyes, because these new molecules exhibit weak or even no fluorescence when they are in free movement states but emit intensely upon the restriction of intramolecular motions. Inspired by the excellent performances of AIE molecules, a substantial number of AIE-based probes have been designed, synthesized, and applied to various fields to fulfill diverse detection tasks. According to numerous experiments, AIE probes are more practical than traditional fluorescent probes, especially when used in bioassays. To bridge bioimaging and materials engineering, this review provides a comprehensive understanding of the development of AIE bioprobes. It begins with a summary of mechanisms of the AIE phenomenon. Then, the strategies to realize accurate detection using AIE probes are discussed. In addition, typical examples of AIE-active materials applied in diagnosis, treatment, and nanocarrier tracking are presented. In addition, some challenges are put forward to inspire more ideas in the promising field of AIE-active materials.


Asunto(s)
Diagnóstico por Imagen , Animales , Técnicas Biosensibles , Sistemas de Liberación de Medicamentos , Fluorescencia , Humanos , Nanopartículas/química
14.
J Cell Mol Med ; 24(3): 2135-2144, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31944568

RESUMEN

Breast cancer is the second leading death cause of cancer death for all women. Previous study suggested that Protein Kinase D3 (PRKD3) was involved in breast cancer progression. In addition, the protein level of PRKD3 in triple-negative breast adenocarcinoma was higher than that in normal breast tissue. However, the oncogenic mechanisms of PRKD3 in breast cancer is not fully investigated. Multi-omic data showed that ERK1/c-MYC axis was identified as a major pivot in PRKD3-mediated downstream pathways. Our study provided the evidence to support that the PRKD3/ERK1/c-MYC pathway play an important role in breast cancer progression. We found that knocking out PRKD3 by performing CRISPR/Cas9 genome engineering technology suppressed phosphorylation of both ERK1 and c-MYC but did not down-regulate ERK1/2 expression or phosphorylation of ERK2. The inhibition of ERK1 and c-MYC phosphorylation further led to the lower protein level of c-MYC and then reduced the expression of the c-MYC target genes in breast cancer cells. We also found that loss of PRKD3 reduced the rate of the cell proliferation in vitro and tumour growth in vivo, whereas ectopic (over)expression of PRKD3, ERK1 or c-MYC in the PRKD3-knockout breast cells reverse the suppression of the cell proliferation and tumour growth. Collectively, our data strongly suggested that PRKD3 likely promote the cell proliferation in the breast cancer cells by activating ERK1-c-MYC axis.


Asunto(s)
Neoplasias de la Mama/genética , Proliferación Celular/genética , Proteína Quinasa Activada por ADN/genética , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteínas Proto-Oncogénicas c-myc/genética , Animales , Mama/patología , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Humanos , Ratones , Ratones Desnudos , Oncogenes/genética , Fosforilación/genética , Transducción de Señal/genética
15.
Nanotechnology ; 31(16): 165503, 2020 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-31891925

RESUMEN

A gas sensor made from graphene vertical field effect transistor (VGr-FET) has been fabricated using graphene as the source electrode, C60 thin film as the semiconductor layer and aluminum thin film as the drain electrode. The on/off ratio of transistor gated by bottom electrode with ionic liquid gel as dielectric layer is derived to be 103 from measured source-drain current I ds. The apparent energy barrier height between the graphene and polycrystalline fullerene was calculated from the model of heterojunction diode I-V response curves. The barrier height φ BH was altered by the gating potential vertically applied on graphene sheet, resulting the large on/off ratio of the transistor. The effect of surface adsorption of water vapor, oxygen, ammonia and isoprene gas phase molecules on the I ds was measured. The lower limit of detection (LOD) for ammonia (86 ppb) than that of isoprene (420 ppb) is attributed to the donor nature of ammonia contact with p-type graphene, and the adsorbed donor leads to a corresponding positive gating effect to the VGr-FET. This facile, low cost and quick responsive device shows promise for early diagnose of severe human respiratory diseases.

16.
Angew Chem Int Ed Engl ; 59(8): 3280-3286, 2020 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-31808280

RESUMEN

The experimental investigation of intermolecular charge transport in π-conjugated materials is challenging. Herein, we describe the investigation of charge transport through intermolecular and intramolecular paths in single-molecule and single-stacking thiophene junctions by the mechanically controllable break junction (MCBJ) technique. We found that the ability for intermolecular charge transport through different single-stacking junctions was approximately independent of the molecular structure, which contrasts with the strong length dependence of conductance in single-molecule junctions with the same building blocks, and the dominant charge-transport path of molecules with two anchors transited from an intramolecular to an intermolecular path when the degree of conjugation increased. An increase in conjugation further led to higher binding probability owing to the variation in binding energies, as supported by DFT calculations.

17.
J Cell Physiol ; 234(12): 21937-21946, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31054187

RESUMEN

Accumulating evidence suggests that noncoding RNAs play a vital role in cancer biology. Circular RNAs (circRNAs), a newly defined class of endogenously widespread noncoding RNAs, have been intensively reported to influence cell function and development, and even cancer prognosis by sponging microRNAs in various types of cancer. Nevertheless, the circRNAs research in hepatocellular carcinoma (HCC) still remains far insufficient. Herein, we investigated the role of a newly defined circRNAs, circ_0005075, in HCC development. We found circ_0005075 was upregulated in HCC tissues. HCC progression was suppressed by downregulation of circ_0005075 in vitro and in vivo, and the suppression was partially reversed by inhibition of microRNA-335 (miR-335) expression. Further, we found the expression of mitogen-activated protein kinase 1 (MAPK1) was substantially regulated by circ_0005075 and miR-335. Mechanically, it was demonstrated that circ_0005075 could directly bind to miR-335 and miR-335 could bind to MAPK1. Our data provide evidence that circ_0005705 promotes the HCC progression by sponging miR-335 and further regulating MAPK1 expression.


Asunto(s)
Carcinoma Hepatocelular/genética , Regulación Neoplásica de la Expresión Génica/genética , Neoplasias Hepáticas/genética , MicroARNs/genética , Proteína Quinasa 1 Activada por Mitógenos/biosíntesis , ARN Circular/genética , Animales , Progresión de la Enfermedad , Xenoinjertos , Humanos , Neoplasias Hepáticas/patología , Ratones , Proteína Quinasa 1 Activada por Mitógenos/genética
18.
Nanotechnology ; 30(26): 26LT01, 2019 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-30836332

RESUMEN

Freestanding graphene films are desired to be widely applied in biosensor fabrication due to their distinctive physical properties and improved performance. Chemical vapor deposition has been developed to efficiently fabricate large-area graphene. However, some of the fabricated graphene films might break or be contaminated in the current transferring step using polymers. A stable and high-quality transfer method is needed. Herein, we report on an advanced transfer method of large-area graphene film which uses fullerene as a supporting substrate. Unlike polymers, which are commonly eliminated by being dissolved in an organic solution, fullerene can be easily removed by evaporation in a vacuum because it has a different heat stability to graphene. By using the improved transferring method, the percentage of integrated freestanding films after transferring was increased from 60.7% to 93.4%. The vacuum is beneficial in terms of keeping the brittle freestanding films intact. Graphene films transferred using fullerene showed an advanced flatness and a simplicial elementary composition in comparison to those transferred using polymers. Even through there is trace residue, this stable allotrope of graphene is considered to have almost no impact on biomolecule sensing. These advantages make the fullerene transferring method an attractive candidate for fabricating large-area freestanding graphene films, especially for using in the field of biochemistry analysis and biosensors.

19.
Chirality ; 31(10): 824-834, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31342574

RESUMEN

Several amino acid chiral ionic liquids were introduced as functional monomers to prepare molecularly imprinted polymers for specific recognition of L-phenylalanine. Among them, the imprinted polymers L-Phe@MIPs based on [ViImC3][L-Pro] showed the best selective recognition ability for L-phenylalanine. A series of experiments such as dynamic adsorption, static adsorption, and competitive adsorption were conducted to investigate the specific recognition ability and adsorption capacity of the L-Phe@MIPs. It is found that the adsorption efficiency to L-phenylalanine on L-Phe@MIPs was 3.11 times higher than that to D-phenylalanine. All the results demonstrated that the L-Phe@MIPs possessed good recognition and relatively high adsorption efficiency for L-phenylalanine. Besides, the recovery of L-phenylalanine was above 98%, and the L-Phe@MIPs exhibited good reusability.

20.
Chirality ; 30(11): 1182-1194, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30188593

RESUMEN

As one kind of functionalized green medium, chiral ionic liquids (CILs) have been widely applied in fields of asymmetric catalysis, enantioseparation, and so on. In this study, four kinds of amino acid-based CILs were synthesized by using trimethylamine, N-methylpyrrolidine, N-methylimidazole, and tropine as cationic nucleus, respectively. Then their specific optical rotation and solubility in common solvents were determined for further resolution application. The effect of different cations in these CILs was explored on the separation of racemic phenylalanine in complex-precipitation way. Moreover, various factors were systematically investigated for their effects on resolution efficiency, including the type of additive copper salts, the molar ratio of Cu (II) to CIL, pH value, the amount of racemic phenylalanine, and temperature. Under the appropriate conditions, L-phenylalanine mainly existed in solid phase and could be separated from its enantiomers in liquid phase. Furthermore, the mechanism of resolution was studied by thermogravimetric analysis, infrared spectrum, and molecular simulation. The resolution system has characteristics of no organic solvent, fast separation speed, simple resolution process, and easy scale-up.

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