Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 205
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Inorg Chem ; 63(25): 11592-11603, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38861349

RESUMEN

In order to take advantage of the distinct reversible multielectron transfer properties of polyoxometalates (POMs) and increase the electron density at the active sites during the electrochemical reduction of CO2 (CO2RR), a range of transition metal-doped polyoxometalates (TMSPOMs) was entrapped within the porphyrin-based framework of PCN-224 via an encapsulation method, known as TMSPOMs@PCN-224 (TMSPOMs = [XW11O39MII(H2O)]n-, [XW11O40VIV]n-, M = CoII, MnII; X = Si, n = 6; X = P, n = 5). The central elements (Si, P) and the incorporated transition metals (VIV, CoII, and MnII) both play a role in adjusting the electronic structure and electron transfer during the CO2RR process. Remarkably, the composite material with cobalt substitution displayed significantly improved performance. Through fine-tuning the POM loading, the electrocatalytic activity was optimized, leading to an impressive Faradaic efficiency for CO production (FECO) of 89.9% for SiW11Co@PCN-224, a significant improvement compared to the 12.1% FECO of PCN-224. Furthermore, the electrochemical stability of this catalyst was demonstrated over 20 h. Comparative analyses involving six composite materials indicated a relationship between the negative charge of the polyanions and their ability to facilitate effective electron transfer, ultimately enhancing the catalyst's performance. Meanwhile, these findings were supported by density functional theory (DFT) calculations.

2.
Altern Ther Health Med ; 30(1): 44-50, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37773677

RESUMEN

This study employs network pharmacology to uncover the pharmacological mechanisms underlying Shen-qi-di-huang decoction's efficacy in treating uremia. We identified a total of 927 differentially expressed genes (DEGs) through differential expression analysis and the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database and analysis platform, of which 607 were downregulated and 320 were upregulated. We also obtained the effective biological components and related target gene information of Chinese herbal medicines such as Renshen, Huangqi, shudihuang, Shanyao, Fuling, Mudanpi, and Shanzhuyu in Shen-qi-di-huang decoction and constructed a regulatory relationship network between molecular components and target genes in Shen-qi-di-huang decoction. We then constructed a protein-protein interaction (PPI) network of 15 targeted genes (RXRA, ND6, CYP1B1, SLPI, CDKN1A, RB1, HIF1A, MYC, HSPB1, IFNGR1, NQO1, IRF1, RASA1, PSMG1 and MAP2K4) using the STRING database and visualized the PPI network using the software Cytoscape. In addition, we revealed the key molecular functions of uremia through Gene Ontology (GO) enrichment analysis, mainly including neuron apoptotic process, cellular response to oxidative stress, regulation of neuron apoptotic process, neuron projection cytoplasm, RNA polymerase II transcription regulator complex, plasma membrane bounded cell projection cytoplasm, NADH and NADPH dehydrogenase (quinone) activity, protein kinase inhibitor and ubiquitin protein ligase binding, etc. Finally, we identified important biological pathways in uremia through Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, which mainly concentrated in Kaposi sarcoma-associated, small cell lung cancer, Gastric cancer, Hepatitis B and C, Hepatocellular carcinoma, Thyroid cancer, Bladder cancer, MAPK signaling pathway, ErbB signaling pathway, Th17 cell differentiation, HIF-1 signaling pathway, Thyroid hormone signaling pathway and Cell cycle, etc. Using integrated bioinformatical analysis, we elucidated key pharmacological mechanisms based on targeted genes, which was enable early identification of patients with uremia and would contribute to early clinical diagnosis and treatment of patients.


Asunto(s)
Carcinoma Hepatocelular , Medicamentos Herbarios Chinos , Neoplasias Hepáticas , Humanos , Farmacología en Red , Transducción de Señal , Apoptosis , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Medicina Tradicional China , Proteína Activadora de GTPasa p120
3.
J Environ Manage ; 359: 120782, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38669884

RESUMEN

Capturing CO2 using clamshell/eggshell-derived CaO adsorbent can not only reduce carbon emissions but also alleviate the impact of trash on the environment. However, organic acid was usually used, high-temperature calcination was often performed, and CO2 was inevitably released during preparing CaO adsorbents from shell wastes. In this work, CaO-based CO2 adsorbent was greenly prepared by calcium-induced hydrogenation of clamshell and eggshell wastes in one pot at room/moderate temperature. CO2 adsorption experiments were performed in a thermogravimetric analyzer (TGA). The adsorption performance of the adsorbents obtained from the mechanochemical reaction (BM-C/E-CaO) was superior to that of the adsorbents obtained from the thermochemical reaction (Cal-C/E-CaO). The CO2 adsorption capacity of BM-C-CaO at 650 °C is up to 36.82 wt%, but the adsorption decay rate of the sample after 20 carbonation/calcination cycles is only 30.17%. This study offers an alternative energy-saving method for greenly preparing CaO-based adsorbent from shell wastes.


Asunto(s)
Dióxido de Carbono , Tecnología Química Verde , Eliminación de Residuos , Tecnología Química Verde/métodos , Dióxido de Carbono/análisis , Dióxido de Carbono/química , Hidrogenación , Temperatura , Exoesqueleto/química , Cáscara de Huevo/química , Eliminación de Residuos/métodos , Adsorción
4.
Yi Chuan ; 46(6): 466-477, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38886150

RESUMEN

Gene knock-in in mammalian cells usually uses homology-directed repair (HDR) mechanism to integrate exogenous DNA template into the target genome site. However, HDR efficiency is often low, and the co-localization of exogenous DNA template and target genome site is one of the key limiting factors. To improve the efficiency of HDR mediated by CRISPR/Cas9 system, our team and previous studies fused different adaptor proteins with SpCas9 protein and expressed them. By using their characteristics of binding to specific DNA sequences, many different CRISPR/SpCas9 donor adapter gene editing systems were constructed. In this study, we used them to knock-in eGFP gene at the 3'-end of the terminal exon of GAPDH and ACTB genes in HEK293T cells to facilitate a comparison and optimization of these systems. We utilized an optimized donor DNA template design method, validated the knock-in accuracy via PCR and Sanger sequencing, and assessed the efficiency using flow cytometry. The results showed that the fusion of yGal4BD, hGal4BD, hLacI, hTHAP11 as well as N57 and other adaptor proteins with the C-terminus of SpCas9 protein had no significant effect on its activity. At the GAPDH site, the donor adapter systems of SpCas9 fused with yGal4BD, hGal4BD, hLacI and hTHAP11 significantly improved the knock-in efficiency. At the ACTB site, SpCas9 fused with yGal4BD and hGal4BD significantly improved the knock-in efficiency. Furthermore, increasing the number of BS in the donor DNA template was beneficial to enhance the knock-in efficiency mediated by SpCas9-hTHAP11 system. In conclusion, this study compares and optimizes multiple CRISPR/Cas9 donor adapter gene editing systems, providing valuable insights for future gene editing applications.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Humanos , Edición Génica/métodos , Células HEK293 , Técnicas de Sustitución del Gen/métodos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo
5.
Yi Chuan ; 46(9): 716-726, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39275871

RESUMEN

Targeted precise point editing and knock-in can be achieved by homology-directed repair(HDR) based gene editing strategies in mammalian cells. However, the inefficiency of HDR strategies seriously restricts their application in precision medicine and molecular design breeding. In view of the problem that exogenous donor DNA cannot be efficiently recruited autonomously at double-stranded breaks(DSBs) when using HDR strategies for gene editing, the concept of donor adapting system(DAS) was proposed and the CRISPR/Cas9-Gal4BD DAS was developed previously. Due to the large size of SpCas9 protein, its fusion with the Gal4BD adaptor is inconvenient for protein expression, virus vector packaging and in vivo delivery. In this study, two novel CRISPR/Gal4BD-SlugCas9 and CRISPR/Gal4BD-AsCas12a DASs were further developed, using two miniaturized Cas proteins, namely SlugCas9-HF derived from Staphylococcus lugdunensis and AsCas12a derived from Acidaminococcus sp. Firstly, the SSA reporter assay was used to assess the targeting activity of different Cas-Gal4BD fusions, and the results showed that the fusion of Gal4BD with SlugCas9 and AsCas12a N-terminals had minimal distraction on their activities. Secondly, the HDR efficiency reporter assay was conducted for the functional verification of the two DASs and the corresponding donor patterns were optimized simultaneously. The results demonstrated that the fusion of the Gal4BD adaptor binding sequence at the 5'-end of intent dsDNA template (BS-dsDNA) was better for the CRISPR/Gal4BD-AsCas12a DAS, while for the CRISPR/Gal4BD-SlugCas9 DAS, the dsDNA-BS donor pattern was recommended. Finally, CRISPR/Gal4BD-SlugCas9 DAS was used to achieve gene editing efficiency of 24%, 37% and 31% respectively for EMX1, NUDT5 and AAVS1 gene loci in HEK293T cells, which was significantly increased compared with the controls. In conclusion, this study provides a reference for the subsequent optimization of the donor adapting systems, and expands the gene editing technical toolbox for the researches on animal molecular design breeding.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Edición Génica/métodos , Humanos , Células HEK293
6.
Zhongguo Zhong Yao Za Zhi ; 49(17): 4812-4817, 2024 Sep.
Artículo en Zh | MEDLINE | ID: mdl-39307816

RESUMEN

Thrombolysis/thrombectomy treatment is an emergency medical intervention for patients with acute ischemic stroke. Its core purpose is to reduce brain tissue damage and improve patient prognosis by restoring blood flow to the brain, which is significantly advantageous in timely restoring blood flow to the brain and reducing post-stroke sequelae. However, research shows that even with successful thrombolysis/thrombectomy treatment, some patients may still experience re-occlusion of the target vessel, leading to secondary damage and worsening of the condition. This study retrospectively examined clinical, experimental, and theoretical aspects of thrombolysis/thrombectomy in both traditional Chinese medicine(TCM) and western medicine, and analyzed the characteristics of blood-activating and stasis-resolving therapy in different stages of thrombolysis/thrombectomy and the synergistic mechanism of different types of blood-activating and stasis-resolving drugs with thrombolysis/thrombectomy in combination of previous clinical studies by the research team. Furthermore, the "vessel hyperactivity" characteristics embodied by Yang vessel irritability and Yin vessel stagnation was explained, revealing the TCM mechanism by which blood-activating TCM drugs reduce the incidence of vessel re-occlusion after thrombolysis/thrombectomy through multiple targets and pathways from a theoretical perspective. It also explored how blood-activating and stasis-resolving drugs promoted the excretion of pathological products such as phlegm, fluid, stasis, and toxins from damaged brain tissue, enhanced self-repair of damaged brain tissue, and accelerated the reconstruction of the brain by facilitating the transformation of Qi, blood, and essence within the body. This study aims to deeply elucidate the TCM theoretical mechanism of blood-activating and stasis-resolving therapy in reducing the occurrence of "cerebral infarction and vascular re-occlusion" during thrombolysis/thrombectomy, which holds significant theoretical and practical significance.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional China , Trombectomía , Terapia Trombolítica , Humanos , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/cirugía
7.
Anal Chem ; 94(12): 4970-4978, 2022 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-35297621

RESUMEN

Thioredoxin reductase (TrxR) is a pivotal antioxidant enzyme, but there remains a challenge for its fast imaging. This work describes the combination of a hydroxyl styrylpyridinium scaffold as the push-pull fluorophore with a carbonate-bridged 1,2-dithiolane unit as the reaction site to develop a fast mitochondrial TrxR2 probe, DSMP. It manifested a plethora of excellent properties including a rapid specific response (12 min), large Stokes shift (170 nm), ratiometric two-photon imaging, favorable binding with TrxR (Km = 12.5 ± 0.2 µM), and the ability to cross the blood-brain barrier. With the aid of DSMP, we visualized the increased mitochondrial TrxR2 activity in cancer cells compared to normal cells. This offers the direct imaging evidence of the connection between the increased TrxR2 activity and the development of cancer. Additionally, the probe allowed the visualization of the loss in TrxR2 activity in a cellular Parkinson's disease model and, more importantly, in mouse brain tissues of a middle cerebral artery occlusion model for ischemic stroke.


Asunto(s)
Colorantes Fluorescentes , Reductasa de Tiorredoxina-Disulfuro , Animales , Diagnóstico por Imagen , Ratones , Mitocondrias , Fotones
8.
Eur J Nucl Med Mol Imaging ; 49(12): 4171-4181, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35781600

RESUMEN

PURPOSE: Thyroid hormone withdrawal (THW) inevitably induced hypothyroidism in patients with differentiated thyroid cancer (DTC), and we aimed to evaluate the safety and efficacy of a novel recombinant human thyroid-stimulating hormone (rhTSH, ZGrhTSH) as an alternative of THW in China. METHODS: Totally, 64 DTC patients were enrolled with 24 in the dose-escalation cohort equally grouped into 0.9 mg × 1 day, 0.9 mg × 2 day, 1.8 mg × 1 day, and 1.8 mg × 2 day dosage, and 40 further enrolled into 0.9 mg × 2 day dose-expansion cohort. All patients underwent both ZGrhTSH phase and levothyroxine (L-T4) withdrawal phase for self-comparison in terms of TSH levels, the radioactive iodine (RAI) uptake, stimulated thyroglobulin level, and the quality of life (QoL). RESULTS: In ZGrhTSH phase, no major serious adverse events were observed, and mild symptoms of headache were observed in 6.3%, lethargy in 4.7%, and asthenia in 3.1% of the patients, and mostly resolved spontaneously within 2 days. Concordant RAI uptake was noticed in 89.1% (57/64) of the patients between ZGrhTSH and L-T4 withdrawal phases. The concordant thyroglobulin level with a cut-off of 1 µg/L was noticed in 84.7% (50/59) of the patients without the interference of anti-thyroglobulin antibody. The QoL was far better during ZGrhTSH phase than L-T4 withdrawal phase, with lower Billewicz (- 51.30 ± 4.70 vs. - 39.10 ± 16.61, P < 0.001) and POMS (91.70 ± 16.70 vs. 100.40 ± 22.11, P = 0.011) scores which indicate the lower the better. Serum TSH level rose from basal 0.11 ± 0.12 mU/L to a peak of 122.11 ± 42.44 mU/L 24 h after the last dose of ZGrhTSH. In L-T4 withdrawal phase, a median of 23 days after L-T4 withdrawal was needed, with the mean TSH level of 82.20 ± 31.37 mU/L. The half-life for ZGrhTSH clearance was about 20 h. CONCLUSION: The ZGrhTSH held the promise to be a safe and effective modality in facilitating RAI uptake and serum thyroglobulin stimulation, with better QoL of patients with DTC compared with L-T4 withdrawal.


Asunto(s)
Adenocarcinoma , Neoplasias de la Tiroides , Tirotropina Alfa , Humanos , Radioisótopos de Yodo/efectos adversos , Calidad de Vida , Hormonas Tiroideas , Neoplasias de la Tiroides/radioterapia , Neoplasias de la Tiroides/cirugía , Tirotropina/uso terapéutico , Tirotropina Alfa/efectos adversos , Tiroxina , Tomografía Computarizada por Rayos X
9.
Ann Vasc Surg ; 86: 380-388, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35595209

RESUMEN

BACKGROUND: This study evaluated aortic remodeling in highly tapered type B aortic dissection (TBAD) patients who underwent thoracic endovascular aortic repair (TEVAR) with a proximal tapered stent graft plus a distal restrictive stent graft to maximize thoracic coverage while avoiding distal excessive oversizing. METHODS: Thirty-four patients presenting with highly tapered TABD were randomized to restricted TEVAR (r-TEVAR) and standard TEVAR groups. Highly tapered TBAD was defined as the maximal diameter of the true lumen at proximal and distal thoracic aorta landing zone tapers greater than 8 mm or taper ratio greater than 20%. Patients in the r-TEVAR group underwent proximal tapered stent grafts plus distal restrictive stent grafts, to match the taper ratio of the descending thoracic aorta (DTA) and extend the length of stent coverage. Patients in the standard TEVAR group underwent proximal tapered stent grafts implantation without distal restrictive stent grafts. Aortic remodeling was estimated by computed tomography angiography (CTA) during the follow-up. RESULTS: In total, 16 patients underwent r-TEVAR, and 18 patients underwent standard TEVAR. The taper ratio of the stent graft matched the DTA in the r-TEVAR group (24.7 ± 3.4% vs. 27.3 ± 4.2%, P = 0.068), but did not match that in the standard TEVAR group (13.5 ± 3.3% vs. 30.5 ± 9.6%, P < 0.001). The length of stent graft coverage in the r-TEVAR group was longer than that in the standard TEVAR group (220.4 ± 21.1 mm vs. 175.3 ± 17.8 mm, P < 0.001). Compared with the standard TEVAR group, the r-TEVAR group had better complete remodeling of the DTA at 6 months (40% vs. 5.6%, P = 0.03), 12 months (60% vs. 16.7%, P = 0.027), and 24 months (78.6% vs. 41.2%, P = 0.036) after the operation. There was no difference in the cumulative survival rate between the r-TEVAR and standard TEVAR groups (P = 0.166). CONCLUSIONS: The r-TEVAR with overlapping proximal tapered stent grafts and distal restrictive stent grafts can match the taper of highly tapered TABD, extend the length of stent graft coverage, and lead to better remodeling of the DTA than standard TEVAR.


Asunto(s)
Aneurisma de la Aorta Torácica , Disección Aórtica , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Humanos , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/métodos , Prótesis Vascular , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/métodos , Aortografía/métodos , Estudios Retrospectivos , Complicaciones Posoperatorias/cirugía , Resultado del Tratamiento , Disección Aórtica/diagnóstico por imagen , Disección Aórtica/cirugía , Stents , Aorta Torácica/diagnóstico por imagen , Aorta Torácica/cirugía
10.
J Environ Manage ; 319: 115617, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-35803071

RESUMEN

The preparation of clean fuel or CO2 adsorbents using industrial and domestic garbage is an alternative way of meeting global energy needs and alleviating environmental problems. Herein, H2-mixed CH4 fuel and CaO-based CO2 sorbent were first prepared in one pot by the mechanochemical reaction of pretreated clamshell or eggshell wastes (carbon and calcium source) with calcium hydride (hydrogen source) at room temperature. In the above reactions, CH4 was the sole hydrocarbon product, and its yield reached 78.23%. The H2/CH4 ratio of the produced H2-mixed CH4 fuel was tunable according to the need by changing the reaction conditions. It is inspiring that the simultaneously formed solid CaO/carbon products were efficient CaO-based sorbents, which possessed a higher CO2 adsorption capacity (49.81-58.74 wt.%) at 650 °C and could maintain good adsorption stability in 30 carbonation/calcination cycles (average activity loss per cycle of only 1.6%). The three achievements of the idea are that it can simultaneously eliminate clamshell or eggshell wastes, obtain valuable clean fuel, and acquire efficient CaO-based sorbents.


Asunto(s)
Compuestos de Calcio , Óxidos , Adsorción , Animales , Calcio , Carbono , Dióxido de Carbono , Cáscara de Huevo , Hidrogenación , Temperatura
11.
Yi Chuan ; 44(8): 708-719, 2022 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-36384669

RESUMEN

The fast-rising CRISPR-derived gene editing technologies has been widely used in the fields of life science and biomedicine, as well as plant and animal breeding. However, the efficiency of homology-directed repair (HDR), an important strategy for gene knock-in and base editing, remains to be improved. In this study, we came up with the term Donor Adapting System (DAS) to summarize those CRISPR/Cas9 systems modified with adaptor for driving aptamer-fused donor DNA. A set of CRISPR/Cas9-Gal4BD DAS was designed in our study. In this system, Gal4 DNA binding domain (Gal4BD) is used as adaptor to fuse with Cas9 protein, and Gal4 binding sequence (Gal4BS) is used as aptamer to bind to the double-stranded DNA (dsDNA) donor, in order to improve the HDR efficiency. Preliminary results from the HEK293T-HDR.GFP reporter cell line show that the HDR editing efficiency could be improved up to 2-4 times when donor homologous arms under certain length (100-60 bp). Further optimization results showed that the choice of fusion port and fusion linker would affect the expression and activity of Cas9, while the Cas9-Gal4BD fusion with a GGS5 linker was the prior choice. In addition, the HDR efficiency was likely dependent on the aptamer-dsDNA donor design, and single Gal4BD binding sequence (BS) addition to the 5'-end of intent dsDNA template was suggested. Finally, we achieved enhanced HDR editing on the endogenous AAVS1 and EMX1 sites by using the CRISPR/Gal4BD-Cas9 DAS, which we believe can be applied to facilitate animal molecular design breeding in the future.


Asunto(s)
Sistemas CRISPR-Cas , Reparación del ADN por Recombinación , Animales , Humanos , ADN , Células HEK293
12.
Anal Chem ; 93(4): 2385-2393, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33439630

RESUMEN

This work highlights the use of push-pull hydroxylphenylpolyenylpyridinium fluorophores coupled with trimethyl lock quinone to engineer the ratiometric two-photon probes for cellular and intravital imaging of mitochondrial NAD(P)H:quinone oxidoreductase 1 (NQO1), a critical antioxidant enzyme responsible for detoxifying quinones. As a typical representative, QBMP showed favorable binding with NQO1 with a Michaelis constant of 12.74 µM and exhibited a suite of superior properties, including rapid response (4 min), large Stokes shift (162 nm), ultralow detection limit (0.9 nM), favorable two-photon cross section for the released fluorophore (70.5 GM), and deep tissue penetration (225 µm) in fixed brain tissues. More importantly, this probe was successfully applied for distinguishing different NQO1-expressing cancer and normal cells, revealing decreased NQO1 activity in a cellular Parkinson's disease model, screening NQO1 inducers as neuroprotective agents, and imaging of NQO1 in live mouse brain.


Asunto(s)
Colorantes Fluorescentes/química , Mitocondrias/metabolismo , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Compuestos de Piridinio/química , Animales , Encéfalo/irrigación sanguínea , Línea Celular , Supervivencia Celular/efectos de los fármacos , Diagnóstico por Imagen , Humanos , Microscopía Intravital/métodos , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , NAD(P)H Deshidrogenasa (Quinona)/química , Compuestos de Piridinio/síntesis química , Compuestos de Piridinio/toxicidad , Ratas , Análisis de la Célula Individual
13.
Cancer Cell Int ; 21(1): 663, 2021 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-34895230

RESUMEN

m6A (N6-methyladenosine) methylation, a well-known modification in tumour epigenetics, dynamically and reversibly fine tunes the entire process of RNA metabolism. Aberrant levels of m6A and its regulators, which can predict the survival and outcomes of cancer patients, are involved in tumorigenesis, metastasis and resistance. Ovarian cancer (OC) ranks first among gynaecological tumours in the causes of death. At first diagnosis, patients with OC are usually at advanced stages owing to a lack of early biomarkers and effective targets. After treatment, patients with OC often develop drug resistance. This article reviews the recent experimental advances in understanding the role of m6A modification in OC, raising the possibility to treat m6A modification and its regulators as promising diagnostic markers and therapeutic targets for OC.

14.
Angew Chem Int Ed Engl ; 59(47): 20779-20793, 2020 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-32633859

RESUMEN

Photo/electrocatalysis of water (H2 O) splitting and CO2 reduction reactions is a promising strategy to alleviate the energy crisis and excessive CO2 emissions. For the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and CO2 reduction reaction (CO2 RR) involved, the development of effective photo/electrocatalysts is critical to reduce the activation energy and accelerate the sluggish dynamics. Polyoxometalate (POM)-based compounds with tunable compositions and diverse structures are emerging as unique photo/electrocatalysts for these reactions as they offer unparalleled advantages such as outstanding solution and redox stability, quasi-semiconductor behaviour, etc. This Minireview provides a basic introduction related to photo/electrocatalytic HER, OER and CO2 RR, followed by the classification of pristine POM-based compounds toward different catalytic reactions. Recent breakthroughs in engineering POM-based compounds as efficient photo/electrocatalysts are highlighted. Finally, the advantages, challenges, strategies and outlooks of POM-based compounds on improving photo/electrocatalytic performance are discussed.

15.
Fish Shellfish Immunol ; 87: 371-378, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30703548

RESUMEN

Thymosin hormones, which were shown to be involved in immune system development and differentiation in previous studies, have antimicrobial functions in different animals. Zebrafish are a useful model for immunology research. Although thymosin has been reported to be involved in the embryonic development of zebrafish, it is necessary to uncover the antimicrobial function of thymosin in zebrafish. In this study, we expressed thymosin ß (Tß) in zebrafish in vitro and studied its antimicrobial function. The Tß protein consists of 45 amino acids and is conserved among its family members, especially the actin-binding motif (LKKTET). Tß was expressed in all tested tissues and was highly expressed in the brain, liver and hindgut. After Aeromonas hydrophila challenge, the Tß transcript level increased in the skin, liver, kidney, spleen, thymus, foregut, gills and midgut. Purified recombinant thymosin ß (rTß) protein was used to study the antimicrobial mechanism. rTß could inhibit the growth of Staphylococcus aureus, Aeromonas hydrophila, Vibrio anguillarum, Pseudomonas aeruginosa and Klebsiella pneumoniae. rTß also binds to and agglutinates certain bacteria. Further study showed that rTß could combine with the polysaccharides from gram-negative and gram-positive bacterial walls. All results suggested that the Tß of zebrafish plays a significant role in innate antibacterial immune responses.


Asunto(s)
Proteínas de Peces/inmunología , Inmunidad Innata/fisiología , Timosina/inmunología , Pez Cebra/inmunología , Aeromonas hydrophila/fisiología , Animales , Enfermedades de los Peces/inmunología , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones por Bacterias Gramnegativas/veterinaria
16.
Angew Chem Int Ed Engl ; 58(48): 17260-17264, 2019 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-31557373

RESUMEN

Over the past 200 years, the most famous and important heteroatom Keggin architecture in polyoxometalates has only been synthesized with Mo, W, V, or Nb. Now, the self-assembly of two phosphate (PO4 3- )-centered polyoxo-titanium clusters (PTCs) is presented, PTi16 and PTi12 , which display classic heteroatom Keggin and its trivacant structures, respectively. Because TiIV has lower oxidate state and larger ionic radius than MoVI , WVI , VV , and NbV , additional TiIV centres in these PTCs are used to stabilize the resultant heteroatom Keggin structures, as demonstrated by the cooresponding theoretical calculation results. These photoactive PTCs can be utilized as efficient photocatalysts for highly selective CO2 -to-HCOOH conversion. This new discovery indicates that the classic heteroatom Keggin family can be assembled with Ti, thus opening a research avenue for the development of PTC chemistry.

17.
Phys Chem Chem Phys ; 20(16): 11116-11122, 2018 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-29623311

RESUMEN

Although recent works demonstrated that some potassium compounds that can be converted to KH during ball-milling or heat-treatment have obvious effects on enhancing the dehydrogenation properties of the Li-N-H system, the effect of KH on enhancing the dehydrogenation properties of the Li-N-H system and its catalytic mechanism remain unclear. In this study, the hydrogen desorption properties of the LiNH2-LiH system with alkali metal hydrides (LiH, NaH, or KH) were investigated and discussed. We find that the three types of hydrides are effective for enhancing the hydrogen desorption properties of the LiNH2-LiH system, among which, KH shows the best effect. In comparison with the broad shaped hydrogen desorption curve of the LiNH2-LiH composite without additive, the hydrogen desorption curve of the LiNH2-LiH-0.05KH composite becomes narrow. The dehydrogenation onset temperature of the LiNH2-LiH-0.05KH composite is decreased by approximately 20 °C, and the dehydrogenation peak temperature is lowered by approximately 30 °C. Moreover, the reversibility of the LiNH2-LiH system is enhanced drastically by the addition of KH. On the basis of previous reports and present experimental results, the mechanism for the enhancement of the dehydrogenation properties in the KH-added Li-N-H system is proposed. The reason for the improvement of the hydrogen desorption kinetics is that KH has superior reactivity with NH3 and plays the role of a catalyst to accelerate hydrogen release by cyclic reactions.

18.
Clin Exp Pharmacol Physiol ; 45(5): 437-443, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29272031

RESUMEN

This retrospective study was performed to evaluate the association between the UGT2B7 tagSNPs (rs12233719, rs4356975, rs7435335 and rs7441774) and breast cancer in Chinese females. Blood samples were collected from 672 patients with breast cancer and 670 healthy controls for DNA extraction. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to analyze UGT2B7 polymorphisms. Dual-luciferase reporter assays were further performed to investigate the regulatory function of UGT2B7 tagSNPs. The frequency of rs7441774 G allele in the breast cancer cases was statistically significantly higher than in the controls (0.412 vs 0.358, P = .006; odds ratio [OR] = 1.27, 95% CI = 1.08-1.48). After adjusting for conventional risk factors, individuals with the GG genotype had a higher breast cancer risk than those with the AA genotype (adjusted OR = 1.63, 95% CI = 1.18-2.26; P = .008). The GCGG haplotype of UGT2B7 was also associated with breast cancer (OR = 1.22, 95% CI = 1.04-1.45; P = .027). Meanwhile, the rs7441774 G allele could significantly decrease the transcriptional activity of the UGT2B7 gene. This study indicates that UGT2B7 polymorphisms may play a crucial role in the occurrence and development of breast cancer in the Han Chinese population.


Asunto(s)
Pueblo Asiatico/genética , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/genética , Predisposición Genética a la Enfermedad/genética , Glucuronosiltransferasa/genética , Polimorfismo de Nucleótido Simple , Femenino , Humanos , Persona de Mediana Edad
19.
J Neurosci ; 36(29): 7663-75, 2016 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-27445144

RESUMEN

UNLABELLED: Anatomical studies have identified brainstem neurons that project bilaterally to left and right oromotor pools, which could potentially mediate bilateral muscle coordination. We use retrograde lentiviruses combined with a split-intein-mediated split-Cre-recombinase system in mice to isolate, characterize, and manipulate a population of neurons projecting to both the left and right jaw-closing trigeminal motoneurons. We find that these bilaterally projecting premotor neurons (BPNs) reside primarily in the supratrigeminal nucleus (SupV) and the parvicellular and intermediate reticular regions dorsal to the facial motor nucleus. These BPNs also project to multiple midbrain and brainstem targets implicated in orofacial sensorimotor control, and consist of a mix of glutamatergic, GABAergic, and glycinergic neurons, which can drive both excitatory and inhibitory inputs to trigeminal motoneurons when optogenetically activated in slice. Silencing BPNs with tetanus toxin light chain (TeNT) increases bilateral masseter activation during chewing, an effect driven by the expression of TeNT in SupV BPNs. Acute unilateral optogenetic inhibition of SupV BPNs identifies a group of tonically active neurons that function to lower masseter muscle tone, whereas unilateral optogenetic activation of SupV BPNs is sufficient to induce bilateral masseter activation both during resting state and during chewing. These results provide evidence for SupV BPNs in tonically modulating jaw-closing muscle tone and in mediating bilateral jaw closing. SIGNIFICANCE STATEMENT: We developed a method that combines retrograde lentiviruses with the split-intein-split-Cre system in mice to isolate, characterize, and manipulate neurons that project to both left and right jaw-closing motoneurons. We show that these bilaterally projecting premotor neurons (BPNs) reside primarily in the supratrigeminal nucleus and the rostral parvicellular and intermediate reticular nuclei. BPNs consist of both excitatory and inhibitory populations, and also project to multiple brainstem nuclei implicated in orofacial sensorimotor control. Manipulation of the supratrigeminal BPNs during natural jaw-closing behavior reveals a dual role for these neurons in eliciting phasic muscle activation and in maintaining basal muscle tone. The retrograde lentivirus carrying the split-intein-split-Cre system can be applied to study any neurons with bifurcating axons innervating two brain regions.


Asunto(s)
Vías Eferentes/fisiología , Lateralidad Funcional/fisiología , Neuronas Motoras/fisiología , Músculo Esquelético/fisiología , Núcleos del Trigémino/citología , Potenciales de Acción/fisiología , Animales , Channelrhodopsins , Potenciales Evocados Motores/genética , Femenino , Lateralidad Funcional/genética , Glutamato Descarboxilasa/genética , Glutamato Descarboxilasa/metabolismo , Humanos , Técnicas In Vitro , Integrasas/genética , Integrasas/metabolismo , Inteínas/fisiología , Masculino , Ratones Endogámicos C57BL , Neurotransmisores/metabolismo , Ratas , Tiempo de Reacción , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Potenciales Sinápticos/genética
20.
Tumour Biol ; 39(5): 1010428317697562, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28459209

RESUMEN

Nowadays, although chemotherapy is an established therapy for breast cancer, the molecular mechanisms of chemotherapy resistance in breast cancer remain poorly understood. This study aims to explore the effects of endoplasmic reticulum stress on autophagy, apoptosis, and chemotherapy resistance in human breast cancer cells by regulating PI3K/AKT/mTOR signaling pathway. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to detect the cell viability of six human breast cancer cell lines (MCF-7, ZR-75-30, T47D, MDA-MB-435s, MDA-MB-453, and MDA-MB-231) treated with tunicamycin (5 µM), after which MCF-7 cells were selected for further experiment. Then, MCF-7 cells were divided into the control (without any treatment), tunicamycin (8 µ), BEZ235 (5 µ), and tunicamycin + BEZ235 groups. Cell viability of each group was testified by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Western blotting was applied to determine the expressions of endoplasmic reticulum stress and PI3K/AKT/mTOR pathway-related proteins and autophagy- and apoptosis-related proteins. Monodansylcadaverine and Annexin V-fluorescein isothiocyanate/propidium iodide staining were used for determination of cell autophagy and apoptosis. Furthermore, MCF-7 cells were divided into the control (without any treatment), tunicamycin (5 µM), cisplatin (16 µM), cisplatin (16 µM) + BEZ235 (5 µM), tunicamycin (5 µM) + cisplatin (16 µM), and tunicamycin (5 µM) + cisplatin (16 µM) + BEZ235 groups. Cell viability and apoptosis were also evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and Annexin V-fluorescein isothiocyanate/propidium iodide staining. In MCF-7 cells treated with tunicamycin, cell viability decreased significantly, but PEAK, eIF2, and CHOP were upregulated markedly and p-PI3K, p-AKT, and p-MTOR were downregulated in dose- and time-dependent manners. In the tunicamycin + BEZ235 group, the cell viability was lower and the apoptosis rate was higher than those of the control and monotherapy groups. Compared with the cisplatin group, the tunicamycin + cisplatin group showed a relatively higher growth inhibition rate; the growth inhibition rate substantially increased in the tunicamycin + cisplatin + BEZ235 group than the tunicamycin + cisplatin group. The apoptosis rate was highest in tunicamycin + cisplatin + BEZ235 group, followed by tunicamycin + cisplatin group and then cisplatin group. Our study provide evidence that endoplasmic reticulum stress activated by tunicamycin could promote breast cancer cell autophagy and apoptosis and enhance chemosensitivity of MCF-7 cells by inhibiting the PI3K/AKT/mTOR signaling pathway.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Resistencia a Antineoplásicos/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Cisplatino/administración & dosificación , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Imidazoles/administración & dosificación , Células MCF-7 , Proteína Oncogénica v-akt/genética , Fosfatidilinositol 3-Quinasas/genética , Quinolinas/administración & dosificación , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/genética , Tunicamicina/administración & dosificación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA