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1.
Nat Commun ; 15(1): 5713, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977661

RESUMO

Cellular senescence is characterized by a decrease in protein synthesis, although the underlying processes are mostly unclear. Chemical modifications to transfer RNAs (tRNAs) frequently influence tRNA activity, which is crucial for translation. We describe how tRNA N7-methylguanosine (m7G46) methylation, catalyzed by METTL1-WDR4, regulates translation and influences senescence phenotypes. Mettl1/Wdr4 and m7G gradually diminish with senescence and aging. A decrease in METTL1 causes a reduction in tRNAs, especially those with the m7G modification, via the rapid tRNA degradation (RTD) pathway. The decreases cause ribosomes to stall at certain codons, impeding the translation of mRNA that is essential in pathways such as Wnt signaling and ribosome biogenesis. Furthermore, chronic ribosome stalling stimulates the ribotoxic and integrative stress responses, which induce senescence-associated secretory phenotype. Moreover, restoring eEF1A protein mitigates senescence phenotypes caused by METTL1 deficiency by reducing RTD. Our findings demonstrate that tRNA m7G modification is essential for preventing premature senescence and aging by enabling efficient mRNA translation.


Assuntos
Senescência Celular , Guanosina , Metiltransferases , Biossíntese de Proteínas , RNA de Transferência , Senescência Celular/genética , RNA de Transferência/metabolismo , RNA de Transferência/genética , Metiltransferases/metabolismo , Metiltransferases/genética , Guanosina/análogos & derivados , Guanosina/metabolismo , Metilação , Humanos , Ribossomos/metabolismo , Envelhecimento/metabolismo , Envelhecimento/genética , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Animais , Fator 1 de Elongação de Peptídeos/metabolismo , Fator 1 de Elongação de Peptídeos/genética , Estabilidade de RNA
2.
Exp Eye Res ; 244: 109944, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38797260

RESUMO

Fungal keratitis (FK) is an infectious keratopathy can cause serious damage to vision. Its severity is related to the virulence of fungus and response of inflammatory. Rosmarinic acid (RA) extracted from Rosmarinus officinalis exhibits antioxidant, anti-inflammatory and anti-viral properties. The aim of this study was to investigate the effect of RA on macrophage autophagy and its therapeutic effect on FK. In this study, we demonstrated that RA reduced expression of proinflammatory cytokine, lessened the recruitment of inflammatory cells in FK. The relative contents of autophagy markers, such as LC3 and Beclin-1, were significantly up-regulated in RAW 264.7 cells and FK. In addition, RA restored mitochondrial membrane potential (MMP) of macrophage to normal level. RA not only reduced the production of intracellular reactive oxygen species (ROS) but also mitochondria ROS (mtROS) in macrophage. At the same time, RA induced macrophage to M2 phenotype and down-regulated the mRNA expression of IL-6, IL-1ß, TNF-α. All the above effects could be offset by the autophagy inhibitor 3-Methyladenine (3-MA). Besides, RA promote phagocytosis of RAW 264.7 cells and inhibits spore germination, biofilm formation and conidial adherence, suggesting a potential therapeutic role for RA in FK.


Assuntos
Aspergilose , Aspergillus fumigatus , Autofagia , Cinamatos , Depsídeos , Infecções Oculares Fúngicas , Macrófagos , Espécies Reativas de Oxigênio , Ácido Rosmarínico , Depsídeos/farmacologia , Animais , Autofagia/efeitos dos fármacos , Camundongos , Aspergilose/tratamento farmacológico , Aspergilose/microbiologia , Aspergilose/metabolismo , Infecções Oculares Fúngicas/microbiologia , Infecções Oculares Fúngicas/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/microbiologia , Cinamatos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Ceratite/microbiologia , Ceratite/tratamento farmacológico , Ceratite/metabolismo , Modelos Animais de Doenças , Células RAW 264.7 , Citocinas/metabolismo , Fagocitose/efeitos dos fármacos
3.
Cytokine ; 179: 156626, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38678810

RESUMO

PURPOSE: To determine the antifungal, anti-inflammatory and neuroprotective effects of resveratrol (RES) in Aspergillus fumigatus (A. fumigatus) keratitis. METHODS: Cytotoxicity assay and Draize eye assay were performed to assess the toxicity of RES. The antifungal effect of RES was assessed by minimal inhibitory concentration, scanning or transmission electron microscopy, propidium iodide uptake assay, and Calcofluor white staining. Phosphorylation of p38 MAPK, mRNA and protein levels of Dectin-1 and related inflammatory factors were measured by qRT-PCR, ELISA and Western blot in vitro and in vivo. Clinical score, HE staining, plate count, and myeloperoxidase test were used to observe the progress of fungal keratitis. IF staining, qRT-PCR, and the Von Frey test were selected to assess the neuroprotective effects of RES. RESULTS: RES suppressed A. fumigatus hyphae growth and altered hyphae morphology in vitro. RES decreased the expression of Dectin-1, IL-1ß and TNF-α, as well as p38 MAPK phosphorylation expression, and also decreased clinical scores, reduced inflammatory cell infiltration and neutrophil activity, and decreased fungal load. RES also protected corneal basal nerve fibers, down-regulated mechanosensitivity thresholds, and increased the mRNA levels of CGRP and TRPV-1.. CONCLUSION: These evidences revealed that RES could exert antifungal effects on A. fumigatus and ameliorate FK through suppressing the Dectin-1/p38 MAPK pathway to down-regulate IL-1ß, IL-6, etc. expression and play protective effect on corneal nerves.


Assuntos
Anti-Inflamatórios , Aspergillus fumigatus , Ceratite , Lectinas Tipo C , Fármacos Neuroprotetores , Resveratrol , Proteínas Quinases p38 Ativadas por Mitógeno , Aspergillus fumigatus/efeitos dos fármacos , Lectinas Tipo C/metabolismo , Ceratite/tratamento farmacológico , Ceratite/metabolismo , Ceratite/microbiologia , Resveratrol/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Fármacos Neuroprotetores/farmacologia , Anti-Inflamatórios/farmacologia , Camundongos , Aspergilose/tratamento farmacológico , Aspergilose/metabolismo , Antifúngicos/farmacologia , Masculino , Transdução de Sinais/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Córnea/efeitos dos fármacos , Córnea/metabolismo
4.
Open Life Sci ; 18(1): 20220768, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38035047

RESUMO

Non-small cell lung cancer (NSCLC) is often driven by mutations in the epidermal growth factor receptor (EGFR) gene. However, rare mutations such as G719X and S768I lack standard anti-EGFR targeted therapies. Understanding the structural differences between wild-type EGFR and these rare mutants is crucial for developing EGFR-targeted drugs. We performed a systematic analysis using molecular dynamics simulations, essential dynamics (ED), molecular mechanics Poisson-Boltzmann surface area, and free energy calculation methods to compare the kinetic properties, molecular motion, and free energy distribution between wild-type EGFR and the rare mutants' structures G719X-EGFR, S768I-EGFR, and G719X + S768I-EGFR. Our results showed that S768I-EGFR and G719X + S768I-EGFR have higher global and local conformational flexibility and lower thermal and global structural stability than WT-EGFR. ED analysis revealed different molecular motion patterns between S768I-EGFR, G719X + S768I-EGFR, and WT-EGFR. The A-loop and αC-helix, crucial structural elements related to the active state, showed a tendency toward active state development, providing a molecular mechanism explanation for NSCLC caused by EGFR S768I and EGFR G719C + S768I mutations. The present study may be helpful in the development of new EGFR-targeted drugs based on the structure of rare mutations. Our findings may aid in developing new targeted treatments for patients with EGFR S768I and EGFR G719X + S768I mutations.

5.
Energy Fuels ; 37(16): 12018-12029, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37609062

RESUMO

The analysis of ash deposition samples by electron microscopy (EM), scanning electron microscopy (SEM)/energy dispersive scanning (EDS), and X-ray diffraction (XRD) was carried out at three sampling points of a one-dimensional furnace (sampling temperatures were TL5 = 960 °C, TL6 = 855 °C, and TL7 = 820 °C, respectively). The improvement of ash deposition characteristics of biomass combustion with the different addition ratios of coal fly ash (CFA) (Mr = 1:1, 1.5:1 or 2:1) and the heterogeneous removal of gas phase alkali metal heterogeneous were studied. The results showed that under the condition of Mr = 1:1, the ash sample presented a three-dimensional porous loose structure like "coral reef" with the rice husk ash as the skeleton and the combustion products of CFA as the bonding point. The spherical and filamentous crystals mainly composed of SiO2, Al2O3, and silicates were distributed in the slag, and the surfaces of these crystals were accompanied by the eutectic composite salt of K-Al-Si with a high melting point, reflecting the heterogeneous curing effect of CFA on the gas phase migration of the alkali metal (K). With the decreasing addition ratio of CFA (Mr = 1.5:1 or 2:1), the spherical and filamentous crystals were increased in the slag. MgO, Fe2O3, and Al2O3 may be involved in the formation of high-temperature refractory Mg-Fe-aluminate, Ca- and Mg-silicate, which were the precursors of the rigid slag. The alkali metals mostly presented in the form of K2O and KCl in the gas-solid conversion under the temperature effect, serving as binders for bridging, agglomeration, and slagging of the above precursors. In addition, the kalium enrichment was accompanied by Al and S in the CFA, indicating that the Al- and S-active sites have obvious adsorption to kalium.

6.
Materials (Basel) ; 16(12)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37374458

RESUMO

This paper mainly used database technology, machine learning, thermodynamic calculation, experimental verification, etc., on integrated computational materials engineering. The interaction between different alloying elements and the strengthening effect of precipitated phases were investigated mainly for martensitic ageing steels. Modelling and parameter optimization were performed by machine learning, and the highest prediction accuracy was 98.58%. We investigated the influence of composition fluctuation on performance and correlation tests to analyze the influence of elements from multiple perspectives. Furthermore, we screened out the three-component composition process parameters with composition and performance with high contrast. Thermodynamic calculations studied the effect of alloying element content on the nano-precipitation phase, Laves phase, and austenite in the material. The heat treatment process parameters of the new steel grade were also developed based on the phase diagram. A new type of martensitic ageing steel was prepared by selected vacuum arc melting. The sample with the highest overall mechanical properties had a yield strength of 1887 MPa, a tensile strength of 1907 MPa, and a hardness of 58 HRC. The sample with the highest plasticity had an elongation of 7.8%. The machine learning process for the accelerated design of new ultra-high tensile steels was found to be generalizable and reliable.

8.
Diabetol Metab Syndr ; 14(1): 188, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36494734

RESUMO

BACKGROUND/PURPOSE: Proliferative diabetic retinopathy (PDR) is a major diabetic microvascular complication, characterized by pathological angiogenesis. This study sets out to investigate the potential molecular mechanism in the angiogenesis during PDR. METHODS: The expression of microRNA-30b (miR-30b) was quantified in a streptozotocin (STZ)-induced mouse model of PDR. The binding affinity between SIRT1 and miR-30b was then identified and validated. After transduction with In-miR-30b or combined with sh-SIRT1, high-glucose (HG)-induced retinal microvascular endothelial cells (RMECs) were co-cultured with extracellular vesicles (EVs) derived from the plasma of PDR mice (plasma-EVs). The proliferation and angiogenesis of RMECs were then detected in vitro. RESULTS: miR-30b expression was upregulated in the retinal tissue of PDR mice. SIRT1 was a target gene of miR-30b and under the negative regulation by miR-30b in RMECs. In contrast, inhibition of miR-30b resulted in elevated SIRT1 expression, thus alleviating the angiogenesis of RMECs. miR-30b was enriched in the plasma-EVs and could be delivered to RMECs, in which miR-30b exerted pro-angiogenic effects. Furthermore, inhibition of miR-30b arrested the progression of PDR in mice by promoting the expression of SIRT1. CONCLUSION: Collectively, the present study pinpointed the involvement of miR-30b delivered by plasma-EVs in PDR angiogenesis, thus laying the basis for the development of novel therapeutic targets for the treatment of PDR.

9.
Materials (Basel) ; 15(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36363168

RESUMO

The Nb4AlC3 MAX phase can be regarded as a TMC structure with stacking faults, which has great potential as a novel solid hydrogen storage material. Herein, we used ab initio calculations for understanding the hydrogen incorporation into Nb4AlC3 MAX phases, including equilibrium structural characteristics, energy changes, electronic structures, bonding characteristics, and diffusion paths. According to the calculated results, H has thermal stability in the interstice of the Nb-Al layer, and the most probable insertion site is an octahedron (3-site) composed of three Nb atoms and three Al atoms. When C vacancies are introduced, the Nb-C layer has a specific storage capacity for H. In addition, Al vacancies can also be used as possible sites for H incorporation. Moreover, the introduction of vacancies significantly increase the hydrogen storage capacity of the MAX phase. According to the electronic structure and bonding characteristics, the excellent hydrogen storage ability of the Nb4AlC3 structure may be due to the formation of ionic bonds between H and Nb/Al. It is worth noting that the H-Al bond in the 1-site is a covalent bond and an ionic bond key mixture. The linear synchronous transit optimization study shows that only H diffusion in Al vacancies is not feasible. In conclusion, the Nb-Al layer in Nb4AlC3 can provide favorable conditions for the continuous insertion and subsequent extraction of H, while the vacancy structure is more suitable for H storage. Our work provides solid theoretical results for understanding the hydrogen incorporation into Nb4AlC3 MAX phases that can be helpful for the design of advanced hydrogen storage materials.

10.
Genes Environ ; 44(1): 17, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606799

RESUMO

BACKGROUND: The principal objective of this project was to investigate the Epidermal Growth Factor Receptor (EGFR) gene mutation characteristics of lung cancer patients, which can provide a molecular basis for explaining the clinicopathological features, epidemiology and use of targeted therapy in lung cancer patients in the coal-producing areas of East Yunnan. METHODOLOGY: We collected 864 pathologically confirmed lung cancer patients' specimens in First People's Hospital of Qujing City of Yunnan Province from September 2016 to September 2021. We thereafter employed Next Generation Sequencing (NGS) technology to detect all exons present in the EGFR gene. RESULTS: The overall mutation frequency of the EGFR gene was 47.22%. The frequency of EGFR gene mutations in the tissue, plasma, and cytology samples were found to be 53.40%, 23.33%, and 62.50%, respectively. Univariate analysis indicated that the coal-producing areas and Fuyuan county origin were significantly associated with relatively low EGFR gene mutation frequency. Female, non-smoking history, adenocarcinoma, non-brain metastasis, and tissue specimens were found to be related to high EGFR gene mutation frequency. Multivariate logistic regression analysis suggested the lung cancer patients in the central area of Qujing City, stage Ia, non-coal-producing areas, non-Fuyuan origin, and non-Xuanwei origin were more likely to develop EGFR gene mutations. The most common mutations were L858R point mutation (33.09%) and exon 19 deletion (19-del) (21.32%). Interestingly, the mutation frequency of G719X (p = 0.001) and G719X + S768I (p = 0.000) in the coal-producing areas were noted to be more significant than those in non-coal-producing regions. CONCLUSION: This findings of this study might be important in establishing the correlation between routine using NGS for EGFR gene mutation diagnosis and clinical practice in the lung cancer patients.

11.
Materials (Basel) ; 14(18)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34576545

RESUMO

In this study, the high-temperature oxidation behavior of a series of AlTiNiCuCox high-entropy alloys (HEAs) was explored. The AlTiNiCuCox (x = 0.5, 0.75, 1.0, 1.25, 1.5) series HEAs were prepared using a vacuum induction melting furnace, in which three kinds of AlTiNiCuCox (x = 0.5, 1.0, 1.5) alloys with different Co contents were oxidized at 800 °C for 100 h, and their oxidation kinetic curves were determined. The microstructure, morphology, structure, and phase composition of the oxide film surface and cross-sectional layers of AlTiNiCuCox series HEAs were analyzed using scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), and X-ray diffraction (XRD). The influence of Co content on the high-temperature oxidation resistance of the HEAs was discussed, and the oxidation mechanism was summarized. The results indicate that, at 800 °C, the AlTiNiCuCox (x = 0.5, 1.0, 1.5) series HEAs had dense oxide films and certain high-temperature oxidation resistance. With increasing Co content, the high-temperature oxidation resistance of the alloys also increased. With increasing time at high temperature, there was a significant increase in the contents of oxide species and Ti on the oxide film surface. In the process of high-temperature oxidation of AlTiNiCuCox series HEAs, the interfacial reaction, in which metal elements and oxygen in the alloy form ions through direct contact reaction, initially dominated, then the diffusion process gradually became the dominant oxidation factor as ions diffused and were transported in the oxide film.

12.
J Inflamm Res ; 14: 1563-1573, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33907437

RESUMO

PURPOSE: The lncRNA small nucleolar RNA host gene 1 (SNHG1) is a cerebral infarction-associated gene, its biological role and mechanism in diabetic retinopathy remain to be illuminated. The present study was designed to investigate the role of SNHG1 in high glucose induced human retinal pigment epithelial cells (ARPE-19). METHODS: ARPE-19 cells were cultured and exposed to 60 mM high glucose for 48h, and 5.5mM glucose-exposed ARPE-19 cells were used as the control. The levels of the epithelial-mesenchymal transition (EMT) markers E-cadherin, ZO-1, vimentin and α-SMA were measured, and the Cell inflammatory response was evaluated by detecting IL-6 and IL-1ß levels. Then, cell migration, proliferation and apoptosis were detected. The expression of the lncRNA SNHG1 in ARPE-19 cells was detected by quantitative real-time PCR. SNHG1 was knocked down by small interfering RNA (siRNA) transfection. The effects of SNHG1 inhibition on inflammation, EMT, migration, proliferation and apoptosis were observed. RESULTS: The results showed that the expression of SNHG1 was significantly increased in ARPE-19 cells exposed to high glucose. Silencing SNHG1 reduced the expression of vimentin, α-SMA, and the expression of inflammatory chemokines IL-6 and IL-1ß, inhibited migration and proliferation, elevated the expression of E-cadherin and ZO-1, and promoted apoptosis in ARPE-19 cells. CONCLUSION: The lncRNA SNHG1 is involved in hyperglycemia-induced EMT and the inflammatory response of ARPE-19 cells and provides a new understanding of the pathogenesis of DR.

13.
Stem Cell Res Ther ; 11(1): 208, 2020 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-32460847

RESUMO

BACKGROUND: Pluripotent stem cells (PSCs), including human embryonic stem cells (hESCs), hold great potential for regenerative medicine and cell therapy. One of the major hurdles hindering the clinical development of PSC-based therapy is the potential risk of tumorigenesis. CD133 (Prominin 1, PROM1) is a transmembrane protein whose mRNA and glycosylated forms are highly expressed in many human cancer cell types. CD133 also serves as a cancer stem cell (CSC) marker associated with cancer progression and patient outcome. Interestingly, CD133 is highly expressed in hESCs as well as in human preimplantation embryos, but its function in hESCs has remained largely unknown. METHODS: CD133 knockout hESC WA26 cell line was generated with CRISPR/Cas9. CD133 knockout and wide type hESC lines were subjected to pluripotency, proliferation, telomere biology, and teratoma tests; the related global changes and underlying mechanisms were further systemically analyzed by RNA-seq. RESULTS: CD133 deficiency did not affect hESC pluripotency or in vivo differentiation into three germ layers but significantly decreased cell proliferation. RNA-seq revealed that CD133 deficiency dysregulated the p53, PI3K-Akt, AMPK, and Wnt signaling pathways. Alterations in these pathways have been implicated in tumor proliferation and apoptotic escape. CONCLUSIONS: Our data imply that CD133 could be an additional target and used as a selective marker to sort and eliminate undifferentiated cells in reducing potential teratoma formation risk of hESCs in regenerative medicine.


Assuntos
Células-Tronco Embrionárias Humanas , Células-Tronco Pluripotentes , Teratoma , Antígeno AC133 , Diferenciação Celular , Proliferação de Células , Humanos , Fosfatidilinositol 3-Quinases , Teratoma/genética
14.
Transl Oncol ; 12(9): 1164-1176, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31207547

RESUMO

Telomere length maintenance is essential for cell proliferation, which is particularly prominent in cancer. We validate that the primary colorectal tumors exhibit heterogeneous telomere lengths but mostly (90%) short telomeres relative to normal tissues. Intriguingly, relatively short telomeres are associated with tumor malignancy as indicated by poorly differentiated state, and these tumors contain more cancer stem-like cells (CSLCs) identified by several commonly used markers CD44, EPHB2 or LGR5. Moreover, promyelocytic leukemia (PML) and ALT-associated PML nuclear bodies (APBs) are frequently found in tumors with short telomeres and high proliferation. In contrast, distant normal tissues rarely or only minimally express PML. Inhibition of PML and APBs by an ATR inhibitor decreases proliferation of CSLCs and organoids, suggesting a potential therapeutic target to progressive colorectal tumors. Together, telomere maintenance underling tumor progression is connected with CSLCs.

15.
J Anal Methods Chem ; 2019: 5451838, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31061742

RESUMO

[This corrects the article DOI: 10.1155/2018/3567647.].

16.
J Anal Methods Chem ; 2018: 3797389, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29850372

RESUMO

Limonin (LIM), a furan-containing limonoid, is one of the most abundant components of Dictamnus dasycarpus Turcz. Recent studies demonstrated that LIM has great potential for inhibiting the activity of drug-metabolizing enzymes. However, the mechanisms of LIM-induced enzyme inactivation processes remain unexplored. The main objective of this study was to identify the reactive metabolites of LIM using liquid chromatography-mass spectrometry. Three nucleophiles, glutathione (GSH), N-acetyl cysteine (NAC), and N-acetyl lysine (NAL), were used to trap the reactive metabolites of LIM in in vitro and in vivo models. Two different types of mass spectrometry, a hybrid quadrupole time-of-flight (Q-TOF) mass spectrometry and a LTQ velos Pro ion trap mass spectrometry, were employed to acquire structural information of nucleophile adducts of LIM. In total, six nucleophile adducts of LIM (M1-M6) with their isomers were identified; among them, M1 was a GSH and NAL conjugate of LIM, M2-M4 were glutathione adducts of LIM, M5 was a NAC and NAL conjugate of LIM, and M6 was a NAC adduct of LIM. Additionally, CYP3A4 was found to be the key enzyme responsible for the bioactivation of limonin. This metabolism study largely facilitates the understanding of mechanisms of limonin-induced enzyme inactivation processes.

17.
J Anal Methods Chem ; 2018: 3567647, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30662787

RESUMO

Dictamnine (4-methoxyfuro[2,3-b]quinolone, DIC), a common furoquinoline alkaloid in the family of Rutaceae, showed diverse biological activities. To investigate the in vivo metabolic pathways of DIC, metabolism of DIC in mice was studied using a high-performance liquid chromatography coupled to electrospray ionization of hybrid linear trap quadrupole orbitrap (HPLC-LTQ-Orbitrap) mass spectrometer. Nine metabolites were identified in the DIC-treated mouse urine, plasma, and fecal samples, of which two were identified as new metabolites. The major metabolic pathways of DIC in animal and human liver microsomes were confirmed in the present study, including o-demethylation, monohydroxylation, N-oxidation, and 2,3-olefinic epoxidation pathways. For the first time, a mono-acetylcysteine conjugate of DIC (M9) was detected from DIC-treated mouse urine and plasma samples, and 4-methoxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acid (M10) and 2-(2,8-dihydroxy-4-methoxyquinolin-3-yl)acetaldehyde (M11) were identified as new metabolites of DIC; furthermore, using an in vitro human fecal incubation model, furo[2,3-b]quinolin-4-ol (M1) was verified to be a microbial demethylated metabolite of DIC. Collectively, the present study provided new information on the in vivo metabolic fate of DIC.

18.
BMC Biol ; 15(1): 114, 2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29216888

RESUMO

BACKGROUND: Telomere length heterogeneity has been detected in various cell types, including stem cells and cancer cells. Cell heterogeneity in pluripotent stem cells, such as embryonic stem cells (ESCs), is of particular interest; however, the implication and mechanisms underlying the heterogeneity remain to be understood. Single-cell analysis technology has recently been developed and effectively employed to investigate cell heterogeneity. Yet, methods that can simultaneously measure telomere length and analyze the global transcriptome in the same cell have not been available until now. RESULTS: We have established a robust method that can simultaneously measure telomere length coupled with RNA-sequencing analysis (scT&R-seq) in the same human ESC (hESC). Using this method, we show that telomere length varies with pluripotency state. Compared to those with long telomere, hESCs with short telomeres exhibit the lowest expressions of TERF1/TRF1, and ZFP42/REX1, PRDM14 and NANOG markers for pluripotency, suggesting that these hESCs are prone to exit from the pluripotent state. Interestingly, hESCs ubiquitously express NOP10 and DKC1, stabilizing components of telomerase complexes. Moreover, new candidate genes, such as MELK, MSH6, and UBQLN1, are highly expressed in the cluster of cells with long telomeres and higher expression of known pluripotency markers. Notably, short telomere hESCs exhibit higher oxidative phosphorylation primed for lineage differentiation, whereas long telomere hESCs show elevated glycolysis, another key feature for pluripotency. CONCLUSIONS: Telomere length is a marker of the metabolic activity and pluripotency state of individual hESCs. Single cell analysis of telomeres and RNA-sequencing can be exploited to further understand the molecular mechanisms of telomere heterogeneity.


Assuntos
Células-Tronco Embrionárias Humanas/fisiologia , RNA/metabolismo , Análise de Sequência de RNA/métodos , Homeostase do Telômero/fisiologia , Telômero/fisiologia , Humanos
19.
Oncol Res Treat ; 40(10): 586-592, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28892804

RESUMO

BACKGROUND: Papillary thyroid cancer (PTC) is the most common differentiated thyroid cancer and is responsible for 80-90% of thyroid cancer cases. Despite typically excellent prognoses, these subclinical low-risk cancers are often treated aggressively by surgical thyroidectomy. Consequently, the objective of this study was to generate a prognostic matrix to be used prior to PTC intervention. METHODS: In this study, 80 PTC patients were assessed. Following adjustment for sex, logistic regression analysis showed that BRAFV600E mutation, transforming growth factor beta (TGF-ß) expression, age, and tumor size are risk factors that can affect tumor clinical stage (p < 0.05). Based on the results of this analysis, we generated a matrix that incorporated 4 variables: patient age, tumor size, BRAFV600E mutation, and TGF-ß expression. RESULTS: We observed that the corresponding area under curve was as high as 0.91. The sensitivity and specificity of the model were 94.74 and 83.61%, respectively. These values are significantly higher than those generated from single indexes. CONCLUSION: As a result of this analysis, it is hoped that the resultant matrix can be utilized during clinical diagnosis and treatment prior to thyroid nodule surgery.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Papilar/genética , Análise Mutacional de DNA , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias da Glândula Tireoide/genética , Fator de Crescimento Transformador beta1/genética , Adolescente , Adulto , Fatores Etários , Idoso , Carcinoma Papilar/diagnóstico , Carcinoma Papilar/patologia , Carcinoma Papilar/cirurgia , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Carga Tumoral
20.
FEBS Open Bio ; 7(8): 1102-1110, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28781951

RESUMO

Interferon-induced transmembrane protein 1 (IFITM1), a member of the IFITM protein family, is a component of a multimeric complex involved in the transduction of antiproliferation and cell adhesion signals. IFITM1 is thought to play a role in antiproliferation and immune surveillance, and has been shown to restrict infection by numerous viruses. It is highly expressed in human embryonic stem cells (hESCs) but its role in hESCs remains to be elucidated. In this study, knockout of IFITM1 mediated by CRISPR/Cas9 in hESCs did not affect self-renewal, pluripotency, telomerase activity or telomeres. However expression of human endogenous retroviruses (HERVs) was higher than in wild-type hESCs, and there was also a reduced level of trimethylation of histone H3 on lysine 9 at HERV loci. These data show that IFITM1 suppresses HERVs in hESCs by regulating epigenetic modifications.

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