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1.
J Transl Med ; 22(1): 622, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965536

RESUMEN

BACKGROUND: Inhibition of kinases is the ever-expanding therapeutic approach to various types of cancer. Typically, assessment of the treatment response is accomplished by standard, volumetric imaging procedures, performed weeks to months after the onset of treatment, given the predominantly cytostatic nature of the kinase inhibitors, at least when used as single agents. Therefore, there is a great clinical need to develop new monitoring approaches to detect the response to kinase inhibition much more promptly. Noninvasive 1H magnetic resonance spectroscopy (MRS) can measure in vitro and in vivo concentration of key metabolites which may potentially serve as biomarkers of response to kinase inhibition. METHODS: We employed mantle cell lymphoma (MCL) cell lines demonstrating markedly diverse sensitivity of inhibition of Bruton's tyrosine kinase (BTK) regarding their growth and studied in-depth effects of the inhibition on various aspects of cell metabolism including metabolite synthesis using metabolomics, glucose and oxidative metabolism by Seahorse XF technology, and concentration of index metabolites lactate, alanine, total choline and taurine by 1H MRS. RESULTS: Effective BTK inhibition profoundly suppressed key cell metabolic pathways, foremost pyrimidine and purine synthesis, the citrate (TCA) cycle, glycolysis, and pyruvate and glutamine/alanine metabolism. It also inhibited glycolysis and amino acid-related oxidative metabolism. Finally, it profoundly and quickly decreased concentration of lactate (a product of mainly glycolysis) and alanine (an indicator of amino acid metabolism) and, less universally total choline both in vitro and in vivo, in the MCL xenotransplant model. The decrease correlated directly with the degree of inhibition of lymphoma cell expansion and tumor growth. CONCLUSIONS: Our results indicate that BTK inhibition exerts a broad and profound suppressive effect on cell metabolism and that the affected index metabolites such as lactate, alanine may serve as early, sensitive, and reliable biomarkers of inhibition in lymphoma patients detectable by noninvasive MRS-based imaging method. This kind of imaging-based detection may also be applicable to other kinase inhibitors, as well as diverse lymphoid and non-lymphoid malignancies.


Asunto(s)
Agammaglobulinemia Tirosina Quinasa , Linfoma de Células del Manto , Inhibidores de Proteínas Quinasas , Humanos , Línea Celular Tumoral , Inhibidores de Proteínas Quinasas/farmacología , Animales , Agammaglobulinemia Tirosina Quinasa/metabolismo , Agammaglobulinemia Tirosina Quinasa/antagonistas & inhibidores , Linfoma de Células del Manto/metabolismo , Linfoma de Células del Manto/patología , Linfoma de Células del Manto/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Biomarcadores de Tumor/metabolismo , Proliferación Celular/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Ratones , Biomarcadores/metabolismo
2.
Int Arch Occup Environ Health ; 97(3): 231-251, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38356028

RESUMEN

BACKGROUND: Although silica is a proven lung carcinogen, there is no convincing evidence linking crystalline silica to gastrointestinal malignancies. METHODS: We detailedly searched studies on the link between gastrointestinal malignancies and occupational silica exposure. Studies published between 1987 and 2023 were found by searching PubMed, Scopus, Cochrane Library, and Web of Science databases. Further studies were included from reference searching. We conducted a meta-analysis of the incidence and mortality of gastrointestinal malignancies and occupational silica exposure. We computed pooled-risk estimates using random effects models. Egger's regression asymmetry test and a funnel plot were used to identify publication bias. Moreover, sensitivity analysis and subgroup analysis were out. RESULTS: We identified 40 research with individuals from 13 different countries. The results indicate that occupational silica exposure raises the risk of gastric and esophageal cancer incidence, with pooled standardized incidence ratio of 1.35 (95% CI 1.21-1.51, p < 0.001), 1.31 (95% CI 1.04-1.65, p = 0.023), respectively, but there was a lack of statistically significant relationship between standardized mortality ratio. In addition, we found that silica exposure did not increase the risk of colorectal and pancreatic cancers. Occupational silica exposure was found to increase the risk of liver cancer, with pooled SIR and SMR of 1.19 (95% CI 1.04-1.35, p = 0.009), 1.24 (95% CI 1.03-1.49, p = 0.026), respectively. CONCLUSIONS: We discovered a link between occupational silica exposure and gastrointestinal malignancies, with cancers of the liver, stomach, and esophagus being the most prevalent. Colorectal and pancreatic cancer were not linked to occupational silica exposure.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Esofágicas , Neoplasias Gastrointestinales , Enfermedades Profesionales , Exposición Profesional , Neoplasias Gástricas , Humanos , Dióxido de Silicio/efectos adversos , Neoplasias Esofágicas/complicaciones , Enfermedades Profesionales/etiología , Exposición Profesional/efectos adversos , Estudios de Cohortes , Neoplasias Gastrointestinales/epidemiología , Neoplasias Gastrointestinales/complicaciones
3.
J Am Chem Soc ; 145(5): 3175-3186, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36705997

RESUMEN

Oxidation-induced strategy for inert chemical bond activation through highly active radical cation intermediate has exhibited unique reactivity. Understanding the structure and reactivity patterns of radical cation intermediates is crucial in the mechanistic study and will be beneficial for developing new reactions. In this work, the structure and properties of indole radical cations have been revealed using time-resolved transient absorption spectroscopy, in situ electrochemical UV-vis, and in situ electrochemical electron paramagnetic resonance (EPR) technique. Density functional theory (DFT) calculations were used to explain and predict the regioselectivity of several electrochemical oxidative indole annulations. Based on the understanding of the inherent properties of several indole radical cations, two different regioselective annulations of indoles have been successfully developed under electrochemical oxidation conditions. Varieties of furo[2,3-b]indolines and furo[3,2-b]indolines were synthesized in good yields with high regioselectivities. Our mechanistic insights into indole radical cations will promote the further development of oxidation-induced indole functionalizations.

4.
Nature ; 552(7683): 57-62, 2017 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-29186115

RESUMEN

Transfer-RNA-derived small RNAs (tsRNAs; also called tRNA-derived fragments) are an abundant class of small non-coding RNAs whose biological roles are not well understood. Here we show that inhibition of a specific tsRNA, LeuCAG3'tsRNA, induces apoptosis in rapidly dividing cells in vitro and in a patient-derived orthotopic hepatocellular carcinoma model in mice. This tsRNA binds at least two ribosomal protein mRNAs (RPS28 and RPS15) to enhance their translation. A decrease in translation of RPS28 mRNA blocks pre-18S ribosomal RNA processing, resulting in a reduction in the number of 40S ribosomal subunits. These data establish a post-transcriptional mechanism that can fine-tune gene expression during different physiological states and provide a potential new target for treating cancer.


Asunto(s)
ARN Pequeño no Traducido/genética , ARN de Transferencia de Leucina/genética , Proteínas Ribosómicas/biosíntesis , Ribosomas/genética , Ribosomas/metabolismo , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Emparejamiento Base , Secuencia de Bases , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/terapia , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Femenino , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/terapia , Masculino , Ratones , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/farmacología , Oligonucleótidos Antisentido/uso terapéutico , Biosíntesis de Proteínas/efectos de los fármacos , Biosíntesis de Proteínas/genética , ARN Mensajero/química , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Ribosómico 18S/genética , ARN Ribosómico 18S/metabolismo , ARN Pequeño no Traducido/antagonistas & inhibidores , ARN de Transferencia de Leucina/antagonistas & inhibidores , Proteínas Ribosómicas/genética , Subunidades Ribosómicas Pequeñas de Eucariotas/metabolismo , Ribosomas/efectos de los fármacos , Especificidad por Sustrato/genética , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Sensors (Basel) ; 23(3)2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36772692

RESUMEN

Text summarization is an information compression technology to extract important information from long text, which has become a challenging research direction in the field of natural language processing. At present, the text summary model based on deep learning has shown good results, but how to more effectively model the relationship between words, more accurately extract feature information and eliminate redundant information is still a problem of concern. This paper proposes a graph neural network model GA-GNN based on gated attention, which effectively improves the accuracy and readability of text summarization. First, the words are encoded using a concatenated sentence encoder to generate a deeper vector containing local and global semantic information. Secondly, the ability to extract key information features is improved by using gated attention units to eliminate local irrelevant information. Finally, the loss function is optimized from the three aspects of contrastive learning, confidence calculation of important sentences, and graph feature extraction to improve the robustness of the model. Experimental validation was conducted on a CNN/Daily Mail dataset and MR dataset, and the results showed that the model in this paper outperformed existing methods.

6.
Sensors (Basel) ; 23(19)2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37836895

RESUMEN

Precipitation nowcasting is mainly achieved by the radar echo extrapolation method. Due to the timing characteristics of radar echo extrapolation, convolutional recurrent neural networks (ConvRNNs) have been used to solve the task. Most ConvRNNs have been proven to perform far better than traditional optical flow methods, but they still have fatal problems. These models lack differentiation in the prediction of echoes of different intensities, which leads to the omission of responses from regions with high intensities. Moreover, because it is difficult for these models to capture long-term feature dependencies among multiple echo maps, the extrapolation effect declines sharply over time. This paper proposes an embedded multi-layer attention module (MLAM) to address the shortcomings of ConvRNNs. Specifically, an MLAM mainly enhances attention to critical regions in echo images and the processing of long-term spatiotemporal features through the interaction between input and memory features in the current moment. Comprehensive experiments were conducted on the radar dataset HKO-7 provided by the Hong Kong Observatory and the radar dataset HMB provided by the Hunan Meteorological Bureau. Experiments show that ConvRNNs embedded with MLAMs achieve more advanced results than standard ConvRNNs.

7.
Sensors (Basel) ; 23(10)2023 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-37430499

RESUMEN

The non-coplanar lasers on both sides of the rail during full-section rail profile measurement based on line-structured light vision will cause the measured profile to be distorted, resulting in measurement errors. Currently, in the field of rail profile measurement, there are no effective methods for evaluating laser plane attitude, and it is impossible to determine the degree of laser coplanarity quantitatively and accurately. This study proposes an evaluation method based on fitting planes in response to this problem. Real-time fitting of laser planes with three planar targets of different heights provides information about the laser plane attitude on both sides of the rails. On this basis, laser coplanarity evaluation criteria were developed to determine whether the laser planes on both sides of the rails are coplanar. Using the method in this study, the laser plane attitude can be quantified and accurately assessed on both sides, effectively resolving the problem with traditional methods that can only assess the laser plane attitude qualitatively and roughly, thereby providing a solid foundation for calibration and error correction of the measurement system.

8.
Angew Chem Int Ed Engl ; 62(17): e202219166, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-36826413

RESUMEN

Precisely introducing two similar functional groups into bulk chemical alkenes represents a formidable route to complex molecules. Especially, the selective activation of two electrophiles is in crucial demand, yet challenging for cross-electrophile-coupling. Herein, we demonstrate a redox-mediated electrolysis, in which aryl nitriles are both aryl radical precursors and redox-mediators, enables an intermolecular alkene 1,2-diarylation with a remarkable regioselectivity, thereby avoiding the involvement of transition-metal catalysts. This transformation utilizes cyanoarene radical anions for activating various aryl halides (including iodides, bromides, and even chlorides) and affords 1,2-diarylation adducts in up to 83 % yield and >20 : 1 regioselectivity with more than 80 examples, providing a feasible approach to complex bibenzyl derivatives.

9.
J Am Chem Soc ; 144(30): 13895-13902, 2022 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-35861667

RESUMEN

Selective cleavage and functionalization of C-C bonds in alcohols is gaining increasing interest in organic synthesis and biomass conversion. In particular, the development of redox-neutral catalytic methods with cheap catalysts and clean energy is of utmost interest. In this work, we report a versatile redox-neutral method for the ring-opening functionalization of cycloalkanols by electrophotochemical (EPC) cerium (Ce) catalysis. The EPC-Ce-enabled catalysis allows for cycloalkanols with different ring sizes to be cleaved while tolerating a broad range of functional groups. Notably, in the presence of chloride as a counteranion and electrolyte, this protocol selectively leads to the formation of C-CN, C-C, C-S, or C-oxime bonds instead of a C-halide bond after ß-scission. A preliminary mechanistic investigation indicates that the redox-active Ce catalyst can be tuned by electro-oxidation and photo-reduction, thus avoiding the use of an external oxidant. Spectroscopic characterizations (cyclic voltammetry, UV-vis, electron paramagnetic resonance, and X-ray absorption fine structure) suggest a Ce(III)/Ce(IV) catalytic pathway for this transformation, in which a Ce(IV)-alkoxide is involved.


Asunto(s)
Cerio , Alcoholes/química , Catálisis , Cerio/química , Espectroscopía de Resonancia por Spin del Electrón , Oxidación-Reducción
10.
J Am Chem Soc ; 143(49): 20863-20872, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34851107

RESUMEN

Electrochemical synthesis has been rapidly developed over the past few years, while a vast majority of the reactions proceed through a radical pathway. Understanding the properties of radical intermediates is crucial in the mechanistic study of electrochemical transformations and will be beneficial for developing new reactions. Nevertheless, it is rather difficult to determine the "live" radical intermediates due to their high reactivity. In this work, the formation and structure of sulfonamide N-centered radicals have been researched directly by using the time-resolved electron paramagnetic resonance (EPR) technique under electrochemical conditions. Supported by the EPR results, the reactivity of N-centered radicals as a mediator in the hydrogen atom transfer (HAT) approach has been discussed. Subsequently, these mechanistic study results have been successfully utilized in the discovery of an unactivated C(sp3)-H arylation reaction. The kinetic experiments have revealed the rate-determined step is the anodic oxidation of sulfonamides.

11.
BMC Med Imaging ; 21(1): 189, 2021 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-34879818

RESUMEN

PURPOSE: The objective of this study is to construct a computer aided diagnosis system for normal people and pneumoconiosis using X-raysand deep learning algorithms. MATERIALS AND METHODS: 1760 anonymous digital X-ray images of real patients between January 2017 and June 2020 were collected for this experiment. In order to concentrate the feature extraction ability of the model more on the lung region and restrain the influence of external background factors, a two-stage pipeline from coarse to fine was established. First, the U-Net model was used to extract the lung regions on each sides of the collection images. Second, the ResNet-34 model with transfer learning strategy was implemented to learn the image features extracted in the lung region to achieve accurate classification of pneumoconiosis patients and normal people. RESULTS: Among the 1760 cases collected, the accuracy and the area under curve of the classification model were 92.46% and 89% respectively. CONCLUSION: The successful application of deep learning in the diagnosis of pneumoconiosis further demonstrates the potential of medical artificial intelligence and proves the effectiveness of our proposed algorithm. However, when we further classified pneumoconiosis patients and normal subjects into four categories, we found that the overall accuracy decreased to 70.1%. We will use the CT modality in future studies to provide more details of lung regions.


Asunto(s)
Aprendizaje Profundo , Diagnóstico por Computador , Neumoconiosis/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Rayos X
12.
Sensors (Basel) ; 20(5)2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32131489

RESUMEN

At present, the method of two-dimensional image recognition is mainly used to detect the abnormal fastener in the rail-track inspection system. However, the too-tight-or-too-loose fastener condition may cause the clip of the fastener to break or loose due to the high frequency vibration shock, which is difficult to detect from the two-dimensional image. In this practical application background, 3D visual detection technology provides a feasible solution. In this paper, we propose a fundamental multi-source visual data detection method, as well as an accurate and robust fastener location and nut or bolt segmentation algorithm. By combining two-dimensional intensity information and three-dimensional depth information generated by the projection of line structural light, the locating of nut or bolt position and accurate perception of height information can be realized in the dynamic running environment of railway. The experimental results show that the static measurement accuracy in the vertical direction using the structural light vision sensor is 0.1 mm under the laboratory condition, and the dynamic measurement accuracy is 0.5 mm under the dynamic train running environment. We use dynamic template matching algorithm to locate fasteners from 2D intensity map, which achieves 99.4% accuracy, then use the watershed algorithm to segment the nut and bolt from the corresponding depth image of located fastener. Finally, the 3D shape of the nut and bolt is analyzed to determine whether the nut or bolt height meets the local statistical threshold requirements, so as to detect the hidden danger of railway transportation caused by too loose or too tight fasteners.

13.
Angew Chem Int Ed Engl ; 59(5): 2080-2084, 2020 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-31724280

RESUMEN

A sensitive amine-responsive disassembly of self-assembled AuI -CuI double salts was observed and its utilization for the synergistic catalysis was enlightened. Investigation of the disassembly of [Au(NHC)2 ][CuI2 ] revealed the contribution of Cu-assisted ligand exchange of N-heterocyclic carbene (NHC) by amine in [Au(NHC)2 ]+ and the capacity of [CuI2 ]- on the oxidative step. By integrating the implicative information coded in the responsive behavior and inherent catalytic functions of d10 metal complexes, a catalyst for the oxidative carbonylation of amines was developed. The advantages of this method were clearly reflected on mild reaction conditions and the significantly expanded scope (51 examples); both primary and steric secondary amines can be employed as substrates. The cooperative reactivity from Au and Cu centers, as an indispensable prerequisite for the excellent catalytic performance, was validated in the synthesis of (un)symmetric ureas and carbamates.

14.
Lab Invest ; 99(10): 1484-1500, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31201367

RESUMEN

A previous study revealed that therapeutic miR-26a delivery suppresses tumorigenesis in a murine liver cancer model, whereas we found that forced miR-26a expression increased hepatocellular carcinoma (HCC) cell migration and invasion, which prompted us to characterize the causes and mechanisms underlying enhanced invasion due to ectopic miR-26a expression. Gain-of-function and loss-of-function experiments demonstrated that miR-26a promoted migration and invasion of BEL-7402 and HepG2 cells in vitro and positively modulated matrix metalloproteinase (MMP)-1, MMP-2, MMP-9, and MMP-10 expression. In addition, exogenous miR-26a expression significantly enhanced the metastatic ability of HepG2 cells in vivo. miR-26a negatively regulated in vitro proliferation of HCC cells, and miR-26a overexpression suppressed HepG2 cell tumor growth in nude mice. Further studies revealed that miR-26a inhibited cell growth by repressing the methyltransferase EZH2 and promoted cell migration and invasion by inhibiting the phosphatase PTEN. Furthermore, PTEN expression negatively correlated with miR-26a expression in HCC specimens from patients with and without metastasis. Thus, our findings suggest for the first time that miR-26a promotes invasion/metastasis by inhibiting PTEN and inhibits cell proliferation by repressing EZH2 in HCC. More importantly, our data also suggest caution if miR-26a is used as a target for cancer therapy in the future.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Neoplasias Hepáticas/metabolismo , MicroARNs/metabolismo , Fosfohidrolasa PTEN/metabolismo , Animales , Movimiento Celular , Femenino , Células Hep G2 , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Metástasis de la Neoplasia
15.
PLoS Genet ; 12(10): e1006308, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27711113

RESUMEN

miR-155 plays critical roles in numerous physiological and pathological processes, however, its function in the regulation of blood glucose homeostasis and insulin sensitivity and underlying mechanisms remain unknown. Here, we reveal that miR-155 levels are downregulated in serum from type 2 diabetes (T2D) patients, suggesting that miR-155 might be involved in blood glucose control and diabetes. Gain-of-function and loss-of-function studies in mice demonstrate that miR-155 has no effects on the pancreatic ß-cell proliferation and function. Global transgenic overexpression of miR-155 in mice leads to hypoglycaemia, improved glucose tolerance and insulin sensitivity. Conversely, miR-155 deficiency in mice causes hyperglycemia, impaired glucose tolerance and insulin resistance. In addition, consistent with a positive regulatory role of miR-155 in glucose metabolism, miR-155 positively modulates glucose uptake in all cell types examined, while mice overexpressing miR-155 transgene show enhanced glycolysis, and insulin-stimulated AKT and IRS-1 phosphorylation in liver, adipose tissue or skeletal muscle. Furthermore, we reveal these aforementioned phenomena occur, at least partially, through miR-155-mediated repression of important negative regulators (i.e. C/EBPß, HDAC4 and SOCS1) of insulin signaling. Taken together, these findings demonstrate, for the first time, that miR-155 is a positive regulator of insulin sensitivity with potential applications for diabetes treatment.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Hiperglucemia/genética , Resistencia a la Insulina/genética , Insulina/genética , MicroARNs/genética , Tejido Adiposo/metabolismo , Tejido Adiposo/patología , Animales , Proliferación Celular/genética , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/metabolismo , Regulación de la Expresión Génica , Glucosa/metabolismo , Humanos , Hiperglucemia/sangre , Hiperglucemia/patología , Insulina/metabolismo , Proteínas Sustrato del Receptor de Insulina/genética , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patología , Ratones , Ratones Transgénicos , MicroARNs/biosíntesis , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Proteínas Proto-Oncogénicas c-akt/genética
16.
Angew Chem Int Ed Engl ; 58(44): 15747-15751, 2019 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-31433101

RESUMEN

An electrochemical method has been developed to achieve arylation of electron-deficient arenes through reductive activation. Various electron-deficient arenes and aryldiazonium tetrafluoroborates are amenable to this transformation within the conditions of an undivided cell, providing the desired products in up to 92 % yield. Instead of preparing diazonium reagents, these reactions can begin from anilines, and they can be carried out in one pot. Electron paramagnetic resonance studies indicate that cathodic reduction of quinoxaline occurs using the transformation. Moreover, cyclic voltammetry indicates that both quinoxaline and aryl diazonium salt have relatively low reduction potentials, which suggests they can be activated through reduction during the reaction.

17.
Lab Invest ; 95(9): 1056-70, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26098000

RESUMEN

The miR-19 family (miR-19a and miR-19b-1) are key oncogenic components of the miR-17-92 cluster. Overexpression of miR-19 is strongly associated with cancer invasion and metastasis, and poor prognosis of cancer patients. However, the underlying mechanisms remain largely unknown. In the present study, we found that enforced expression of miR-19 including miR-19a and miR-19b-1 triggered epithelial-mesenchymal transition (EMT) of lung cancer cells A549 and HCC827 as shown by mesenchymal-like morphological conversion, downregulation of epithelial proteins (e.g., E-cadherin, ZO-1 (zona occludens 1), and α-catenin), upregulation of mesenchymal proteins (e.g., vimentin, fibronectin 1, N-cadherin, and snail1), formation of stress fibers, and reduced cell adhesion. In addition, enhanced migration and invasion were observed in the cancer cells A549 and HCC827 undergoing EMT. In contrast, silencing of endogenous miR-19 reversed EMT and reduced the migration and invasion abilities of A549 and HCC827 cells. DNA microarray results revealed significant changes of the expression of genes related to EMT, migration, and metastasis of miR-19-expressing A549 cells. Moreover, siRNA-mediated knockdown of PTEN, a target of miR-19, also resulted in EMT, migration, and invasion of A549 and HCC827 cells, suggesting that PTEN is involved in miR-19-induced EMT, migration and invasion of lung cancer cells. Furthermore, lung cancer cells undergoing EMT induced by miR-19 demonstrated reduced proliferation in vitro and in vivo, and enhanced resistance to apoptosis caused by TNF-α. Taken together, these findings suggest that miR-19 triggers EMT, which has an important role in the invasion and migration of lung cancer cells, accompanied by the reduced proliferation of cells.


Asunto(s)
Transición Epitelial-Mesenquimal/fisiología , Regulación Neoplásica de la Expresión Génica/fisiología , Neoplasias Pulmonares/fisiopatología , MicroARNs/metabolismo , Animales , Antígenos CD/metabolismo , Western Blotting , Cadherinas/metabolismo , Adhesión Celular/efectos de los fármacos , Línea Celular Tumoral , Transición Epitelial-Mesenquimal/efectos de los fármacos , Fibronectinas/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Luciferasas , Ratones , Ratones Endogámicos BALB C , MicroARNs/farmacología , Análisis de Secuencia por Matrices de Oligonucleótidos , Interferencia de ARN , Factores de Transcripción de la Familia Snail , Sales de Tetrazolio , Tiazoles , Factores de Transcripción/metabolismo , Ensayo de Tumor de Célula Madre , Vimentina/metabolismo , Proteína de la Zonula Occludens-1/metabolismo , alfa Catenina/metabolismo
18.
Mol Divers ; 19(4): 737-43, 2015 11.
Artículo en Inglés | MEDLINE | ID: mdl-26162533

RESUMEN

Fourteen novel pterostilbene (1) and [Formula: see text]-methoxy pterostilbene (2) Mannich base derivatives (3-16) were synthesized via the microwave-assisted Mannich reaction of 1 or 2 with various secondary amines and formaldehyde. The regioselectivity of the reaction occurred preferentially at [Formula: see text] position of the B-ring of stilbene. The biological testing results showed that all the target compounds exhibit antiproliferative activity against Hela cells from [Formula: see text]-[Formula: see text]. Compounds 1-3, 7, 11-13, and 16 displayed higher (lower [Formula: see text] values) activity than the positive control cisplatin [Formula: see text].


Asunto(s)
Antineoplásicos/síntesis química , Estilbenos/síntesis química , Estilbenos/farmacología , Proliferación Celular/efectos de los fármacos , Células HeLa , Humanos , Bases de Mannich , Estructura Molecular
19.
Int J Surg Case Rep ; 120: 109867, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38870658

RESUMEN

INTRODUCTION: Solid pseudopapillary neoplasms (SPNs) of the pancreas are rare neoplasms, accounting for only 1 %-2 % of all pancreatic tumors, and predominantly affect female patients. CASE PRESENTATION: The present case report details a patient presenting to the emergency department with abdominal pain for 3 days who ultimately received a diagnosis of SPNs in the pancreatic body and tail. A contrast-enhanced computed tomography (CT) scan revealed a sizable mass arising from the pancreas, featuring an enhancing cystic component with involvement of the liver and spleen. The patient underwent subsequent exploratory laparotomy, a distal pancreatectomy, splenectomy, and partial hepatectomy. SPN diagnosis was confirmed by histopathology and immunohistochemistry with negative resection margins. CLINICAL DISCUSSION: Approximately 70 % of SPN cases are asymptomatic and are incidentally discovered. Despite advances in diagnostic modalities, preoperative diagnosis of SPNs remains a clinical challenge. Surgical management with negative resection margins remains the primary treatment approach. The recurrence rate after surgical resection has been reported to be 3 %-9 %. The prognosis for SPNs limited to the pancreas is generally favorable, with a cure rate exceeding 95 % after complete surgical resection. CONCLUSION: An SPN of the pancreas is a rare tumor observed in young female patients. Although it is classified as a malignant tumor, SPN has low malignant potential. Aggressive surgical resection, however, has proven effective in curing SPN for the majority of patients.

20.
Nat Commun ; 15(1): 4186, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760336

RESUMEN

Arylamines, serving as crucial building blocks in natural products and finding applications in multifunctional materials, are synthesized on a large scale via an electrophilic nitration/reduction sequence. However, the current methods for aromatic C-H amination have not yet attained the same level of versatility as electrophilic nitration. Here we show an extensively investigated transition metal-free and regioselective strategy for the amination of nitrobenzenes, enabling the synthesis of 4-nitro-N-arylamines through C(sp2)-H/N-H cross-coupling between electron-deficient nitroarenes and amines. Mechanistic studies have elucidated that the crucial aspects of these reactions encompass the generation of nitrogen radicals and recombination of nitrobenzene complex radicals. The C(sp2)-N bond formation is demonstrated to be highly effective for primary and secondary arylamines as well as aliphatic amines under mild conditions, exhibiting exceptional tolerance towards diverse functional groups in both nitroarenes and amines (>100 examples with yields up to 96%). Notably, this C(sp2)-H/N-H cross-coupling exhibits exclusive para-selectivity.

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