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1.
BMC Cancer ; 24(1): 358, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509498

RESUMEN

BACKGROUND: The prognostic significance of tumor burden score (TBS) in relation to carcinoembryonic antigen (CEA) has not been investigated among patients undergoing hepatectomy for intrahepatic cholangiocarcinoma (ICC). This study aimed to develop and validate a simplified model, a combination of TBS and CEA (CTC grade), for predicting the long-term outcomes of postoperative ICC patients. METHODS: Patients who underwent curative - intent resection of ICC between 2011 and 2019 were identified from a large multi - institutional database. The impact of TBS, CEA, and the CTC grade on overall survival (OS) and recurrence - free survival (RFS) was evaluated in both the derivation and validation cohorts. The receiver operating characteristic curve was utilized for assessing the predictive accuracy of the model. Subgroup analyses were performed across 8th TNM stage system stratified by CTC grade to assess the discriminatory capacity within the same TNM stage. RESULTS: A total of 812 patients were included in the derivation cohort and 266 patients in the validation cohort. Survival varied based on CEA (low: 36.7% vs. high: 9.0%) and TBS (low: 40.3% vs. high: 17.6%) in relation to 5 - year survival (both p < 0.001). As expected, patients with low CTC grade (i.e., low TBS/low CEA) were associated with the best OS as well as RFS, while high CTC grade (i.e., high TBS/high CEA) correlated to the worst outcomes. The model exhibited well performance in both the derivation cohort (area under the curve of 0.694) and the validation cohort (0.664). The predictive efficacy of the CTC grade system remains consistently stable across TNM stages I and III/IV. CONCLUSION: The CTC grade, a composite parameter derived from the combination of TBS and CEA levels, served as an easy - to - use tool and performed well in stratifying patients with ICC relative to OS and RFS.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Humanos , Hepatectomía , Antígeno Carcinoembrionario , Carga Tumoral , Colangiocarcinoma/patología , Pronóstico , Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/patología , Estudios Retrospectivos
2.
BMC Cancer ; 23(1): 1190, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38053048

RESUMEN

BACKGROUND: Routine clinical staging for hepatocellular carcinoma (HCC) incorporates liver function, general health, and tumor morphology. Further refinement of prognostic assessments and treatment decisions may benefit from the inclusion of tumor biological marker alpha-fetoprotein (AFP) and systemic inflammation indicator C-reactive protein (CRP). METHODS: Data from a multicenter cohort of 2770 HCC patients undergoing hepatectomy were analyzed. We developed the PACE risk score (Prognostic implications of AFP and CRP Elevation) after initially assessing preoperative AFP and CRP's prognostic value. Subgroup analyzes were performed in BCLC cohorts A and B using multivariable Cox analysis to evaluate the prognostic stratification ability of the PACE risk score and its complementary utility for BCLC staging. RESULTS: Preoperative AFP ≥ 400ng/mL and CRP ≥ 10 mg/L emerged as independent predictors of poorer prognosis in HCC patients who underwent hepatectomy, leading to the creation of the PACE risk score. PACE risk score stratified patients into low, intermediate, and high-risk groups with cumulative 5-year overall (OS) and recurrence-free survival (RFS) rates of 59.6%/44.9%, 43.9%/38.4%, and 20.6%/18.0% respectively (all P < 0.001). Increased PACE risk scores correlated significantly with early recurrence and extrahepatic metastases frequency (all P < 0.001). The multivariable analysis identified intermediate and high-risk PACE scores as independently correlating with poor postoperative OS and RFS. Furthermore, the PACE risk score proficiently stratified the prognosis of BCLC stages A and B patients, with multivariable analyses demonstrating it as an independent prognostic determinant for both stages. CONCLUSION: The PACE risk score serves as an effective tool for postoperative risk stratification, potentially supplementing the BCLC staging system.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , alfa-Fetoproteínas/metabolismo , Proteína C-Reactiva , Carcinoma Hepatocelular/cirugía , Estudios de Cohortes , Hepatectomía , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos
3.
Bioorg Med Chem Lett ; 60: 128586, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35085721

RESUMEN

Menadione (VK3) is used as a powerful inducer of cellular reactive oxygen species (ROS) for many years and displays the high anti-cancer activities in vivo. Recently, the development of mitochondria-targeted drugs has been more and more appreciated. Here, the thirteen derivatives of VK3 were synthesized, which could localize in mitochondria by the triphenylphosphonium (TPP) cation or the nitrogen-based cation. The results of cytotoxicity from six human cancer cell lines showed that the targeted compounds T1-T13 displayed higher activity than VK3 with the average IC50 value around 1 µM. The results of cytotoxicity indicated that the substitutes on C-2, the linear alkyl chains on C-3 and cation moiety all could affect the cytotoxicity. The mechanistic studies showed that five representative compounds (T2, T3, T5, T8 and T13) could localize in cellular mitochondria, elicit ROS burst and collapse mitochondrial membrane potential (ΔΨm), leading to cytochrome C release and apoptosis in MGC-803 cells. Particularly, they could obviously inhibit mitochondrial thioredoxin reductase TrxR2 expression, thus leading to aggravate cellular oxidative stress.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Tiorredoxina Reductasa 2/antagonistas & inhibidores , Vitamina K 3/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Cationes/síntesis química , Cationes/química , Cationes/farmacología , Línea Celular , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Mitocondrias/metabolismo , Estructura Molecular , Relación Estructura-Actividad , Tiorredoxina Reductasa 2/metabolismo , Vitamina K 3/síntesis química , Vitamina K 3/química
4.
Bioorg Chem ; 127: 106037, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35863132

RESUMEN

The seventeen ferulic acid amide derivatives were synthesized by coupling mitochondrial carrier coumarin-3-carboxamide with acrylic acids. The results of cellular antioxidant activity and inhibitory effects on NO production against LPS-stimulated RAW264.7 macrophages indicated four compounds (8c, 8d, 9c, 9d) showed the higher dual-activities of antioxidant and anti-inflammatory. The structure-activity relationship was deduced. In regard to mechanism research, the most potent compound 8d which mainly distributed in mitochondria suppressed the secretion of inflammatory cytokines IL-6 and TNF-α, enhancing mitophagy to alleviate inflammatory response. Besides, the dual-activities were diminished by removal of coumarin carrier in 8d, suggesting the enrichment in mitochondria might be important for activities. This study showed that development of mitochondria-targeted antioxidants could be a feasible strategy to resist inflammation.


Asunto(s)
Antioxidantes , Lipopolisacáridos , Amidas/farmacología , Animales , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Ácidos Cumáricos , Cumarinas , Lipopolisacáridos/farmacología , Ratones , Mitocondrias , Mitofagia , Células RAW 264.7
5.
Sensors (Basel) ; 22(14)2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35891064

RESUMEN

Multilayer perceptron (MLP) has been demonstrated to implement feedforward control of the piezoelectric actuator (PEA). To further improve the control accuracy of the neural network, reduce the training time, and explore the possibility of online model updating, a novel recurrent neural network named PEA-RNN is established in this paper. PEA-RNN is a three-input, one-output neural network, including one gated recurrent unit (GRU) layer, seven linear layers, and one residual connection in the linear layers. The experimental results show that the displacement linearity error of piezoelectric ceramics reaches 8.96 µm in the open-loop condition. After using PEA-RNN compensation, the maximum displacement error of piezoelectric ceramics is reduced to 0.465 µm at the operating frequency of 10 Hz, which proves that PEA-RNN can accurately compensate piezoelectric ceramics' dynamic hysteresis nonlinearity. At the same time, the training epochs of PEA-RNN are only 5% of the MLP, and fewer training epochs provide the possibility to realize online updates of the model in the future.


Asunto(s)
Redes Neurales de la Computación , Pisum sativum , Cerámica , Transductores
6.
J Cardiovasc Pharmacol ; 78(1): e112-e121, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34173806

RESUMEN

ABSTRACT: Diabetic retinopathy is a frequent complication of diabetes mellitus and one of the common causes of blindness. Circular RNAs (circRNAs) can modulate various biological behaviors of human diseases. Circ_0084043 is a novel circRNA, and its function in diabetic retinopathy progression is unclear. Adult retinal pigment epithelial cells (ARPE-19) were treated with high glucose (HG). RNA levels of circ_0084043, microRNA-128-3p (miR-128-3p), and thioredoxin-interacting protein (TXNIP) were detected by quantitative real-time polymerase chain reaction. 3-(4, 5-dimethylthiazole-2-y1)-2, 5-diphenyl tetrazolium bromide and flow cytometry were, respectively, used to examine cell viability and apoptosis. Apoptotic and TNXIP relative protein levels were measured by Western blot. The combination between targets was analyzed through dual-luciferase reporter assay or RNA immunoprecipitation assay. Results showed that HG induced the upregulation of circ_0084043 and the downregulation of miR-128-3p in ARPE-19 cells. Circ_0084043 knockdown or miR-128-3p overexpression mitigated the HG-mediated cell viability inhibition, apoptosis promotion, and inflammatory response. Circ_0084043 targeted miR-128-3p and miR-128-3p inhibitor returned the regulation of si-circ_0084043 in HG-treated cells. TXNIP was the target gene of miR-128-3p and TXNIP overexpression abolished the miR-128-3p-mediated effects after HG treatment. Circ_0084043 regulated the TXNIP expression to activate Wnt/ß-catenin signal pathway by targeting miR-128-3p. Our findings unraveled that circ_0084043 promoted the HG-induced retinal pigment epithelial cell injury through activating the Wnt/ß-catenin signal pathway by the miR-128-3p/TXNIP axis. Circ_0084043 might be an available biomarker in diabetic retinopathy diagnosis and therapy.


Asunto(s)
Apoptosis/efectos de los fármacos , Proteínas Portadoras/metabolismo , Retinopatía Diabética/metabolismo , Células Epiteliales/efectos de los fármacos , Glucosa/toxicidad , MicroARNs/metabolismo , ARN Circular/metabolismo , Epitelio Pigmentado de la Retina/efectos de los fármacos , Vía de Señalización Wnt/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteínas Portadoras/genética , Línea Celular , Citocinas/genética , Citocinas/metabolismo , Retinopatía Diabética/genética , Retinopatía Diabética/patología , Células Epiteliales/metabolismo , Células Epiteliales/patología , Regulación de la Expresión Génica , Humanos , Mediadores de Inflamación/metabolismo , MicroARNs/genética , ARN Circular/genética , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/patología
7.
Bioorg Med Chem Lett ; 33: 127750, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33340662

RESUMEN

Targeting specific mitochondrial alterations to kill cancer cells without affecting their normal counterparts emerges as a feasible strategy. Coumarin derivatives have demonstrated the potential anti-breast cancer activities. By coupling coumarin-3-carboxamide derivatives with mitochondria carrier triphenylphosphonium, mitocoumarins 15a-c were produced and tested as the anti-breast cancer fluorescence agents. Among them, 15b as the amide-based drug potently suppressed the cell growth in MCF-7, MDA-231, SK-BR-3 breast cancer cells with the IC50 values from 3.0 to 4.1 µM, including the lower cytotoxicity to normal MCF-10A cells with the IC50 value around 45.30 ± 2.45 µM. In mechanistic study for 15b in MDA-MB-231 cells, it could localize in mitochondria to elicit ROS burst and collapse Δψm. Besides, it could deplete GSH by an irreversible alkylation process and moderately inhibit mitochondrial thioredoxin reductase TrxR2, thus leading to aggravate cellular oxidative stress. This study reported 15b might be useful for the further development into a mitochondria-targeted anti-triple negative breast cancer drug.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Cumarinas/farmacología , Colorantes Fluorescentes/farmacología , Mitocondrias/efectos de los fármacos , Tiorredoxina Reductasa 2/antagonistas & inhibidores , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cumarinas/síntesis química , Cumarinas/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/química , Humanos , Mitocondrias/metabolismo , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad , Tiorredoxina Reductasa 2/metabolismo
8.
J Cell Mol Med ; 24(2): 1276-1285, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31774937

RESUMEN

TIM-4 plays an important role in ischaemia-reperfusion injury of liver and kidney; however, the effects of TIM-4 on cerebral ischaemia-reperfusion injury (IRI) are unknown. The purpose of the present study was to investigate the potential role of TIM-4 in experimental brain ischaemia-reperfusion injury. In this study, cerebral ischaemia reperfusion was induced by transient middle cerebral artery occlusion (MCAO) for 1 hour in C57/BL6 mice. The TIM-4 expression was detected in vivo or vitro by real-time quantitative polymerase chain reaction, Western blot and flow cytometric analysis. In vivo, the administration of anti-TIM-4 antibodies significantly suppressed apoptosis, inhibited inflammatory cells and enhanced anti-inflammatory responses. In vitro, activated microglia exhibited reduced cellular proliferation and induced IRI injury when co-cultured with neurons; these effects were inhibited by anti-TIM-4 antibody treatment. Similarly, microglia transfected with TIM-4 siRNA and stimulated by LPS + IFN-γ alleviated the TIM-4-mediated damage to neurons. Collectively, our data indicate that the inhibition of TIM-4 can improve the inflammatory response and exerts a protective effect in cerebral ischaemia-reperfusion injury.


Asunto(s)
Isquemia Encefálica/prevención & control , Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media/complicaciones , Proteínas de la Membrana/antagonistas & inhibidores , Sustancias Protectoras , ARN Interferente Pequeño/genética , Daño por Reperfusión/prevención & control , Animales , Isquemia Encefálica/etiología , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Masculino , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Daño por Reperfusión/etiología , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Transducción de Señal
9.
Biomacromolecules ; 21(12): 5233-5240, 2020 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-33258599

RESUMEN

A one-pot strategy was applied to synchronize enzymatic monomer transformation with reversible addition fragmentation chain transfer (RAFT) polymerization for the synthesis of glycopolymers with highly branched gradient architectures. Also, the linear analogues, block glycopolymers, and gradient glycopolymers were also synthesized for comparison. The binding ability of glycopolymers toward bacteria was then studied by optical density (OD) test, confocal laser scanning microscopy (CLSM), and quartz crystal microbalance with dissipation (QCM-D). The results show that the highly branched gradient glycopolymers have the most remarkable bacteria-binding ability compared with the two linear analogues, gradient glycopolymers, and block glycopolymers. The highly branched glycopolymers were further used as inhibitors in the anti-infection test, demonstrating a significant inhibitory effect on preventing bacteria from infecting the cells.


Asunto(s)
Polímeros , Tecnicas de Microbalanza del Cristal de Cuarzo , Bacterias , Polimerizacion
10.
Macromol Rapid Commun ; 41(13): e2000135, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32483937

RESUMEN

Microgel nanoreactors maintain the stability of metallic nanoparticles and regulate their catalytic activity. However, limited by the synthetic method, the recycling ability and long-lasting stability of microgel nanoreactors are challenged. Herein, a brand-new nanoparticle carrier, ultralow crosslinked poly(N-isopropylacrylamide-b-methacrylic acid) (P(NIPAm-b-MAA)) microgel, is synthesized based on the reversible addition-fragmentation chain transfer polymerization method and the self-crosslinking mechanism of PNIPAm. This carrier enables the easy preparation, low cost, long-lasting stability, and high catalytic efficiency of nanoreactors. As far as it is known, the catalytic reduction rates of several dye models used in this work are the highest ones in similar systems. In addition, the presence of the MAA block leads to the agglomeration and dispersion of the microgels under different pH conditions, thus realizing rapid recycling of the nanoreactors. This novel carrier has great potential for a wide range of applications in catalysis.


Asunto(s)
Microgeles , Catálisis , Geles , Polimerizacion , Polímeros
11.
J Synchrotron Radiat ; 26(Pt 6): 1911-1916, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31721733

RESUMEN

Elliptical polarized undulators (EPUs) are broadly used in the soft X-ray energy range. They have the advantage of providing photons with both varied energy and polarization through adjustments to the value of the gap and/or shift magnet arrays in an undulator. Yet these adjustments may create a disturbance on the stability of the electron beam in a storage ring. To correct such a disturbance, it is necessary to establish a feed-forward table of key nodes in the gap-shift-defined two-dimensional parameter space. Such a table can only be scanned during machine-study time. For a free-walking mode, whereby an undulator is allowed to manoeuvre in the whole gap-shift space, all the key nodes need to be scanned at the expense of a large amount of machine-study time. This will greatly delay the employment of a full-polarization capable undulator (especially circularly polarized). By analyzing data-collecting patterns of user experiments, this paper defines a reduced set of key nodes in gap-shift parameter space, with the number of key nodes to be scanned for feed-forwarding scaled down to one-third of the original; and introduces a new walking mode for EPUs: confined-walking mode, whereby the undulator is manoeuvred only within the reduced set of key nodes. Such a mode is firstly realized on the EPUs at the DREAMLINE beamline at Shanghai Synchrotron Radiation Facility (SSRF). Under confined-walking mode, the undulator movements are stable and there is no obvious disturbance to the electron beam with the feed-forward system in operation. Successful experiments have been carried out using the circularly polarized light obtained via the new walking mode. This mode is expected to be applied to future EPUs at SSRF with the increasing requirements for various polarization modes.

12.
Sheng Li Xue Bao ; 71(4): 671-679, 2019 Aug 25.
Artículo en Zh | MEDLINE | ID: mdl-31440764

RESUMEN

The skeletal muscle mass accounts for more than 40% of the body weight of healthy adults. The skeletal muscle not only plays an important role in physical activities but also affects the function of other organs as a secretory organ secreting multiple muscle factors. Therefore, it is important to maintain the normal quantity and function of skeletal muscle. Skeletal muscle mass is the basis of skeletal muscle function and is often affected by many factors such as exercise and disease. Resistance exercise training induces increased protein synthesis in skeletal muscle cells, while limb disuse, chronic obstructive pulmonary disease, heart failure, chronic kidney disease, cachexia, Duchenne muscular dystrophy and many other pathological conditions lead to decreased protein synthesis or enhanced protein degradation of skeletal muscle cells. The process of skeletal muscle hypertrophy involves changes in multiple signaling pathways, such as IGF-1/PI3K/Akt, myostatin and G protein. On the other hand, activations of the ubiquitin-proteasome system, IGF-1/Akt/FoxO, autophagy-lysosomal pathway, NF-κB, and the glucocorticoid-mediated signaling pathways play important roles in regulating muscle atrophy. These signaling pathways regulate skeletal muscle mass and are modulated by some different conditions. This review briefly summarizes the signaling pathways of skeletal muscle mass control.


Asunto(s)
Músculo Esquelético/fisiología , Transducción de Señal , Humanos , Atrofia Muscular , Tamaño de los Órganos
13.
Sheng Li Xue Bao ; 71(3): 497-504, 2019 Jun 25.
Artículo en Zh | MEDLINE | ID: mdl-31218342

RESUMEN

Insulin resistance is a common pathophysiological mechanism of obesity and type 2 diabetes mellitus. Skeletal muscle is one of the major target organs of insulin-mediated glucose uptake, metabolism and utilization, and it is the earliest and most important site of insulin resistance. Studies have shown that the impairments of glucose uptake, insulin signaling pathway and mitochondrial biosynthesis are closely related to skeletal muscle insulin resistance. When insulin resistance develops in skeletal muscle, multiple microRNAs (miRNAs) are up-regulated (miR-106b, miR-23a, miR-761, miR-135a, Let-7 and miR-29a) or down-regulated (miR-133a, miR-149 and miR-1). They participate in the regulation of skeletal muscle glucose uptake, insulin signaling pathway and mitochondrial biogenesis, and thus play important roles in the occurrence and development of skeletal muscle insulin resistance. Therefore, these miRNAs may serve as potential targets for the treatment of skeletal muscle insulin resistance or diabetes.


Asunto(s)
Resistencia a la Insulina , MicroARNs/genética , Músculo Esquelético/fisiología , Diabetes Mellitus Tipo 2 , Humanos , Insulina
14.
Opt Express ; 26(11): 13721-13729, 2018 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-29877420

RESUMEN

We designed and fabricated a 4-channel silicon micro-ring modulator (MRM) assembly chip with arrayed grating couplers for space-division-multiplexed optical interconnection. Only 4 channels out of 7 have been utilized with the consideration of popular multi-source-agreements (MSA) compatibility with respect to a 7-core multi-core-fiber (MCF). Experimental modulations at 10, 15, 20 and 25 Gbps have been carried out for all the four channels with clearly opened eye-diagrams which indicates a single-fiber aggregate capacity of 100 Gbps with only one laser input for SDM optical interconnection. The silicon MRM assembly demonstrated in this work is advantageous for practical applications due to its simplified modulation solution (NRZ-OOK) with high capacity (100-Gbps), small footprint (0.45 mm2) and long reach (1 km).

15.
Bioorg Med Chem Lett ; 28(3): 273-277, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29305189

RESUMEN

The 1,4-naphthoquinone derivatives bearing 5,7-dimethoxyl moiety were designed, synthesized, and tested as the antitumor agents against five human cancer cell lines (A549, Hela, HepG2, NCI-H460 and HL-60). All the compounds are described herein for the first time. The structure-activity relationships indicated that the presence of chlorine atom at the 2-position was crucial for the antiproliferative activity. Further, the electrochemical properties of the representative compounds (7e, 8e and 9e) were evaluated and a definite correlation between the redox potential and the antiproliferative activity. The most potent compound 9e displayed significant anti-leukemic activity with IC50 value of 3.8 µM in HL-60 cells and weak cytotoxicity with IC50 of 40.7 µM in normal cells WI-38. In mechanistic study for 9e, the increased numbers of apoptotic cells and increased cell population at G2/M phase correlated with ROS generation. Together, our results suggested that the derivatives of 2-chlorine-1,4-naphthoquinone might be the promising candidates for the treatment of promyelocytic leukemia.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Naftoquinonas/farmacología , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células HL-60 , Humanos , Células K562 , Estructura Molecular , Naftoquinonas/síntesis química , Naftoquinonas/química , Especies Reactivas de Oxígeno/metabolismo , Relación Estructura-Actividad
16.
Bioorg Med Chem ; 26(14): 4191-4200, 2018 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-30007564

RESUMEN

2-Chloro-3-alkyl-1,4-naphthoquinone derivatives were synthesized and tested as the anti-acute myeloid leukaemia agents. The compound 9b (2-chloro-3-ethyl-5,6,7-trimethoxy-1,4-naphthoquinone) was the most potent toward HL-60 leukaemia cells. In mechanistic study for 9b, the protein levels of mtDNA-specific DNA polymerase γ (poly-γ) and mtDNA transcription factor A (mt-TFA) were decreased after the 24 h treatment, showing the occurrence of mtDNA damage. And 9b triggered cell cycle arrest at S phase accompanied by a secondary block in G2/M phase which had a direct link to the process of mtDNA damage. The dissipations of mitochondrial membrane potential and ATP also proceeded. On the other hand, 9b promoted the generation of ROS and resulted in the oxidation of intracellular GSH to GSSG. This process was coupled to the formation of adduct between 9b and GSH, detected by the UV-Vis spectrum and HRMS analysis. Depletion of GSH by buthionine sulfoximine enhanced ROS level and produced higher cytotoxicity, suggesting GSH was involved in the anti-leukemic mechanism of 9b. Together, our results provide new insights on the molecular mechanism of the derivatives of 2-chloro-1,4-naphthoquinone and 9b might be useful for the further development into an anti-leukemia agent.


Asunto(s)
Antineoplásicos/farmacología , ADN Mitocondrial/efectos de los fármacos , Glutatión/antagonistas & inhibidores , Leucemia Mieloide Aguda/tratamiento farmacológico , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Daño del ADN , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Glutatión/metabolismo , Humanos , Leucemia Mieloide Aguda/patología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Estructura Molecular , Relación Estructura-Actividad , Células Tumorales Cultivadas
17.
Sheng Li Xue Bao ; 69(3): 344-350, 2017 Jun 25.
Artículo en Zh | MEDLINE | ID: mdl-28638928

RESUMEN

Under normal condition, there are a few lipid droplets in skeletal muscle. But in skeletal muscle acute injury, muscular dystrophy, muscle atrophy, obesity, diabetes and other pathological conditions, the fat deposition in skeletal muscle increases, which implicate that the fat deposition may play an important role in the pathogenesis of these diseases. However, the mechanisms of development and regulation of fat deposition in skeletal muscle are not clear. Clarifying the key signaling pathways and regulatory factors that affect fat deposition in skeletal muscle, and exploring new ways to improve the fat deposition in skeletal muscle will not only help to deepen our understanding of the pathogenesis of these diseases, but also provide new ideas for the treatment of these diseases. This paper reviews the research progresses and main mechanisms of fat deposition in skeletal muscle.


Asunto(s)
Tejido Adiposo/fisiología , Músculo Esquelético/fisiología , Animales , Diabetes Mellitus , Humanos , Atrofia Muscular , Distrofias Musculares , Obesidad , Transducción de Señal
18.
J Comput Aided Mol Des ; 30(12): 1189-1200, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27848066

RESUMEN

R-bicalutamide, a first generation antiandrogen, was used to treat prostate cancer for decades. Although it is very effective at the beginning, resistance appears after 2-3 years of treatment. Mutation of androgen receptor (AR) is considered a main reason for drug resistance. It is reported that AR W741C, W741L, W741C_T877A, T877A, F876L, F876L_T877A and L701H mutations can convert R-bicalutamide from AR antagonist to agonist, but the switching mechanisms are not clear. In this study, molecular dynamics simulations and molecular mechanics generalized Born surface area (MM-GBSA) calculations were performed to analyze the interaction mechanisms between R-bicalutamide and wild type/mutant ARs. The results indicate that helix H12, which lies on the top of AR LBD like a cover, plays a vital role in R-bicalutamide binding. When interacting with AR, the B-ring of R-bicalutamide pushes H12 aside, distorting the coactivator binding site (AF2) resulting in the inactivation of transcription. Several residue mutations appear to enlarge the distance between the B-ring of R-bicalutamide and H12, reducing steric clash, which is conducive to a closed H12 conformation, leading to the formation of the coactivator binding site AF2 and increased transcription. Hydrogen bond and per-residue free energy decomposition analyses are also investigated to explore the interacting mechanisms, and M895 is found to be a key residue in the antagonist mechanism. The obtained molecular mechanisms will aid rational screening and design of novel AR antagonists, even to mutant AR.


Asunto(s)
Aminoácidos/genética , Antagonistas de Receptores Androgénicos/química , Andrógenos/química , Anilidas/química , Antineoplásicos/química , Nitrilos/química , Receptores Androgénicos/química , Compuestos de Tosilo/química , Sitios de Unión , Resistencia a Antineoplásicos , Humanos , Masculino , Conformación Molecular , Simulación de Dinámica Molecular , Mutación , Receptores Androgénicos/genética , Estereoisomerismo , Relación Estructura-Actividad , Termodinámica
19.
Sheng Li Ke Xue Jin Zhan ; 47(6): 407-12, 2016 Dec.
Artículo en Zh | MEDLINE | ID: mdl-29894111

RESUMEN

Skeletal muscle repair after injury includes three stages which are inflammation, repair and tissue remodeling. The ability of Skeletal muscle to regenerate in response to injury is solely dependen on the activation, proliferation and differentiation of satellite cells. After skeletal muscle injury, hepatocyte growth factor (HGF) can regular muscle satellite cell function in the manner of autocrine, paracrine or endocrine, thus affecting the regeneration of damaged skeletal muscle. Studies about the mechanism have shown that HGF may bind to its receptor, e-met, to start the relevant signaling pathways involved in skeletal muscle satellite cell activation, proliferation, differentiation and migration, which affects skeletal muscle regeneration process.


Asunto(s)
Factor de Crecimiento de Hepatocito/fisiología , Músculo Esquelético/crecimiento & desarrollo , Regeneración/fisiología , Animales , Diferenciación Celular , Células Cultivadas , Transducción de Señal
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(8): 2324-8, 2015 Aug.
Artículo en Zh | MEDLINE | ID: mdl-26672318

RESUMEN

A novel time-resolved X-ray excited optical luminescence (TRXEOL) experiment system was developed for X ray absorption fine structure spectroscopy(XAFS) beamline at Shanghai Synchrotron Radiation Facility (SSRF). The TRXEOL system is composed of three parts: timing system, spectrometer system and nuclear instrument module (NIM) system. These three systems were integrated to measure and record the optical luminescence from the sample excited by the synchrotron X-ray pulses, according to the time-correlated single photon counting methodology. It's the first time in the domestic synchrotron radiation facilities to achieve TRXEOL experiment using the synchrotron X-ray pulses and the time structure of the storage ring. In this work, a SSRF-self-developed timing system was used, which is based on the Field programmable Gate Array and the high-speed serial communication technology. The timing system can provide trigger pulse synchronized with the X-ray pulse. The timing jitter is about 6 ps, and the timing delay resolution is 5 ps. The NIM system is the core of the TRXEOL experiment system, it has three main modules: the Constant Fraction Discriminator (CFD), the Time to Amplitude Converter (TAC) and the Multi-Channel Analyzer (MCA). During one excitation circle, the spectrometer and the Photomultiplier Tube detector translate the induced luminescence of the sample excited by a single X-ray pulse into electrical pulse. The CFD module eliminates the timing walk larger than 50 ps induced by the amplitude of the electrical pulse. The TAC module calculates the time interval between the timing trigger pulse and the luminescence electrical pulse, and converts the interval into proportional amplitude of voltage. After plenty of circles, the MCA module gets the luminescence decay curve by recording and analyzing the voltage signals. And the data acquisition system gets the TRXEOL spectra by scanning the spectrometer and acquiring the frequency of the voltage pulses from the TAC module. The TRXEOL experiment system helps researchers measure optical decay curves and spectra of the sample in different time windows. Many luminescence behaviors would be explained more deeply, together with the aid of the optical XAFS to get the electron structure of the sample. A sample of ZnO nanowire was studied using the TRXEOL system. The ordinary XEOL spectrum obtained could distinguish the 390 nm wavelength and the 500 nm wavelength luminescence center. The decay curve at 0 nm wavelength could clearly show the fast luminescence process and the slow luminescence process. The full width at half maximum of the fast luminescence decay curve was about 0.5 ns, showing that the minimum time resolution of the TRXEOL system is less than 1 ns. The TRXEOL spectra obtained could respectively get the luminescence information within different time windows. It was demo nstrated that the TRXEOL system is not only feasible and reliable, but also supply XAFS beamline with the technical preparatio ns of time resolved techniques.

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