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1.
Small ; : e2402761, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953299

RESUMO

Flexible rechargeable Zn-air batteries (FZABs) exhibit high energy density, ultra-thin, lightweight, green, and safe features, and are considered as one of the ideal power sources for flexible wearable electronics. However, the slow and high overpotential oxygen reaction at the air cathode has become one of the key factors restricting the development of FZABs. The improvement of activity and stability of bifunctional catalysts has become a top priority. At the same time, FZABs should maintain the battery performance under different bending and twisting conditions, and the design of the overall structure of FZABs is also important. Based on the understanding of the three typical configurations and working principles of FZABs, this work highlights two common strategies for applying bifunctional catalysts to FZABs: 1) powder-based flexible air cathode and 2) flexible self-supported air cathode. It summarizes the recent advances in bifunctional oxygen electrocatalysts and explores the various types of catalyst structures as well as the related mechanistic understanding. Based on the latest catalyst research advances, this paper introduces and discusses various structure modulation strategies and expects to guide the synthesis and preparation of efficient bifunctional catalysts. Finally, the current status and challenges of bifunctional catalyst research in FZABs are summarized.

2.
Small ; : e2400201, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-39031757

RESUMO

Water electrolysis has become an attractive hydrogen production method. Oxygen evolution reaction (OER) is a bottleneck of water splitting as its four-electron transfer procedure presents sluggish reaction kinetics. Designing composite catalysts with high performance for efficient OER still remains a huge challenge. Here, the P-doped cobalt oxide/NiFe layered double hydroxides (P-CoOX/NiFe LDHs) composite catalysts with amorphous/crystalline interfaces are successfully prepared for OER by hydrothermal-electrodeposition combined method. The results of electrochemical characterizations, operando Raman spectra, and DFT theoretical calculations have demonstrated the electrons in the P-CoOX/NiFe LDHs heterointerfaces are easily transferred from Ni2+ to Co3+ because that the amorphous configuration of P-CoOX can well induce Ni-O-Co orbital coupling. The electron transfer of Ni2+ to the surrounding Fe3+ and Co3+ will lead to the unoccupied eg orbitals of Ni3+ that can promote water dissociation and accelerate *OOH migration to improve OER catalytic performance. The optimized P-CoOX/NiFe LDHs exhibit superior catalytic performance for OER with a very low overpotential of 265 mV at 300 mA cm-2 and excellent long-term stability of 500 h with almost no attenuation at 100 mA cm-2. This work will provide a new method to design high-performance NiFe LDHs-based catalysts for OER.

3.
Inorg Chem ; 63(24): 11438-11449, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38833708

RESUMO

Ethanethiol (EtSH), being highly toxic, flammable, and explosive, poses significant risks to human health and safety and is capable of causing fires and explosions. Room-temperature detection using chemiresistive gas sensors is essential for managing these risks. However, the gas-sensing performance of conventional metal-oxide sensing materials may be limited by their weak interaction with EtSH at room temperature. Herein, SnO2 nanoflowers assembled with non-noble Cu-site-enriched porous nanosheets were designed and prepared by an in situ self-template pyrolysis synthesis strategy to enable highly sensitive and selective room-temperature detection of EtSH. By regulating the number of non-noble Cu sites, these nanoflowers achieved efficient EtSH sensing with a Ra/Rg value of 11.0 at 50 ppb, ensuring high selectivity, reproducibility, and stability at room temperature. Moreover, a comparative analysis of the room-temperature gas-sensing performance of SnO2 nanoflowers with non-noble Fe- or Ni-site-enriched nanosheets highlights the benefits of non-noble Cu sites for EtSH detection. Density functional theory (DFT) analysis reveals that non-noble Cu sites have a unique affinity for EtSH, offering preferential binding over other gases and explaining the outstanding sensing performance of non-noble Cu-site-enriched nanosheet-assembled SnO2 nanoflowers. The structural and interface engineering of the sensing materials presented in this work provides a promising approach for offering efficient and durable gas sensors operable at room temperature.

4.
Inorg Chem ; 63(19): 8925-8937, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38683480

RESUMO

The development of efficient urea oxidation reaction (UOR) catalysts helps UOR replace the oxygen evolution reaction (OER) in hydrogen production from water electrolysis. Here, we prepared Fe-doped Ni2P/NiSe2 composite catalyst (Fe-Ni2P/NiSe2-12) by using phosphating-selenizating and acid etching to increase the intrinsic activity and active areas. Spectral characterization and theoretical calculations demonstrated that electrons flowed through the Ni-P-Fe-interface-Ni-Se-Fe, thus conferring high UOR activity to Fe-Ni2P/NiSe2-12, which only needed 1.39 V vs RHE to produce the current density of 100 mA cm-2. Remarkably, this potential was 164 mV lower than that required for the OER under the same conditions. Furthermore, EIS demonstrated that UOR driven by the Fe-Ni2P/NiSe2-12 exhibited faster interfacial reactions, charge transfer, and current response compared to OER. Consequently, the Fe-Ni2P/NiSe2-12 catalyst can effectively prevent competition with OER and NSOR, making it suitable for efficient hydrogen production in UOR-assisted water electrolysis. Notably, when water electrolysis is operated at a current density of 40 mA cm-2, this UOR-assisted system can achieve a decrease of 140 mV in the potential compared to traditional water electrolysis. This study presents a novel strategy for UOR-assisted water splitting for energy-saving hydrogen production.

5.
Inorg Chem ; 63(8): 3702-3711, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38335057

RESUMO

A long-term goal of rechargeable zinc-air batteries (ZABs) has always been to design bifunctional electrocatalysts that are robust, effective, and affordable for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). It has become a feasible method to construct metal/metal oxide interfaces to achieve superior electrocatalytic performance for ORR and OER by enhanced charge transfer. In this study, Co/Co3O4 heterojunctions were successfully prepared and encased in porous N-doped mesoporous carbon (Co/Co3O4@NC) via a simple condensation-carbonization-etching method. The extensive specific surface area of Co/Co3O4@NC facilitates effective interaction between the electrolyte and the catalyst, thereby enabling sufficient exposure of active sites for the ORR and the OER, consequently enhancing the rate of transport of active species. The well-designed Co/Co3O4@NC delivers superior ORR catalytic activity with a half-wave potential of 0.82 V (vs RHE) and a low overpotential of 347 mV at 10 mA cm-2 for OER in alkaline solution. The power density of Co/Co3O4@NC-based alkaline aqueous ZAB (156.5 mW cm-2) is superior to the commercial Pt/C + IrO2-based alkaline aqueous ZAB, and the cycling stability of ZAB is up to 220 h. In addition, Co/Co3O4@NC-based ZAB shows a high power density (50.1 mW cm-2). The construction of metal/metal oxide heterojunction encased in N-doped mesoporous carbon provides a novel route for the design of bifunctional electrocatalysts for high-performance ZABs.

6.
J Chem Phys ; 160(11)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38501473

RESUMO

We establish a theoretical model to analyze the photoassociative spectroscopy of 85Rb 133Cs molecules in the (3)3Σ+ state. The vibrational energy, spin-spin coupling constant, and hyperfine interaction constant of the (3)3Σ+ state are determined based on nine observed vibrational levels. Consequently, the Rydberg-Klein-Rees potential energy curve of the (3)3Σ+ state is obtained and compared with the ab initial potential energy curve. Our model can be adopted to analyze the photoassociative spectroscopy of other heteronuclear alkali-metal diatomic molecules in the (3)3Σ+ state.

7.
J Clin Nurs ; 33(3): 1076-1083, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38041239

RESUMO

AIMS AND OBJECTIVES: The aim of this study was to investigate the relationship between burnout and post-traumatic stress disorder (PTSD) among frontline nurses who went to assist the epidemic situation in Wuhan, China, during the outbreak in 2020. The study also explored the mediating role of depression and the moderating role of age in the main relationship. BACKGROUND: The relationship between burnout and PTSD in nurse has rarely been investigated in the context of the COVID-19 pandemic. Understand the relationship between these variables can provide empirical evidence for developing interventions and protocols that improve the health of nurses in future public health emergencies. DESIGN: An online cross-sectional survey of targeted local 327 nurses who went to assist the COVID-19 epidemic situation in Wuhan during the initial outbreak. METHODS: This study was conducted in August 2020, the burnout scale, the PTSD scale and the depression scale were used to survey participants. The moderated mediation model was used to test research hypotheses. RESULTS: Burnout could affect the PTSD symptoms in nursing staffs and depression could mediate this relationship. Age moderated the relationship between burnout/depression and PTSD, and the effects was strong and significant among younger participants in the relationship between burnout and PTSD. CONCLUSIONS: Burnout was identified as a core risk factor of PTSD in nurses. Depression and age played significant roles in the relationship between burnout and PTSD. RELEVANCE TO CLINICAL PRACTICE: PTSD, as a symptom that manifests after experiencing a stressful event, should be a key concern among frontline healthcare professionals. This study suggests that PTSD in nurses can be further reduced by reducing burnout. Attention should also be paid to the PTSD status of nurses of different age groups. PATIENT OR PUBLIC CONTRIBUTION: Patients and the public were not involved in the design and implementation of this study. Frontline nurses completed an online questionnaire for this study.


Assuntos
Esgotamento Profissional , COVID-19 , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Estudos Transversais , Análise de Mediação , Pandemias , COVID-19/epidemiologia , Esgotamento Psicológico , Esgotamento Profissional/epidemiologia
8.
Small ; 19(45): e2301130, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37434036

RESUMO

Compared with the traditional electrolysis of water to produce hydrogen, urea-assisted electrolysis of water to produce hydrogen has significant advantages and has received extensive attention from researchers. Unfortunately, urea oxidation reaction (UOR) involves a complex six-electron transfer process leading to high overpotential, which forces researchers to develop high-performance UOR catalysts to drive the development of urea-assisted water splitting. Based on the UOR mechanism and extensive literature research, this review summarizes the strategies for preparing highly efficient UOR catalysts. First, the UOR mechanism is introduced and the characteristics of excellent UOR catalysts are pointed out. Aiming at this, the following modulation strategies are proposed to improve the catalytic performance based on summarizing various literature: 1) Accelerating the active phase formation to reduce initial potential; 2) Creating double active sites to trigger a new UOR mechanism; 3) Accelerating urea adsorption and promoting C─N bond cleavage to ensure the effective conduct of UOR; 4) Promoting the desorption of CO2 to improve stability and prevent catalyst poisoning; 5) Promoting electron transfer to overcome the inherent slow dynamics of UOR; 6) Increasing active sites or active surface area. Then, the application of UOR in electrochemical devices is summarized. Finally, the current deficiencies and future directions are discussed.

9.
J Chem Phys ; 158(13): 134302, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37031158

RESUMO

The increase of the number of the two-body recombination channels strongly challenges the numerical calculation of the accurate rates for the three-body recombination (TBR) process and its reverse process, collision-induced dissociation (CID), at ultracold temperatures. By taking the 4He-4He-20Ne collision system as an example, we have obtained the rates for its TBR and CID processes involving all four recombination channels, including the two-body states 4He2 (l = 0) and 4He20Ne (l = 0, 1, 2) with l the rotational quantum number. By using the adiabatic hyperspherical method, we have considered not only total angular momentum J = 0 but also J > 0 in the ultracold collision energies (E = 0.01 - 100 mK × kB). It is found that 4He2 (l = 0) is the major product after the TBR process in the ultracold limit (E ≤ 0.1 mK × kB). The TBR rate into 4He2 (l = 0) is nearly one order of magnitude larger than the sum of the other three products, 4He20Ne (l = 0, 1, 2). Moreover, the CID rates for the three 4He20Ne (l = 0, 1, 2) + 4He initial states are close to each other and are smaller than that for the 4He2 (l = 0) + 20Ne initial state. Additionally, we have, for the first time, performed the channel-resolved scattering calculation that can explain the above-mentioned findings quantitatively.

10.
Zhonghua Nan Ke Xue ; 29(9): 842-845, 2023 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-38639599

RESUMO

OBJECTIVE: To evaluate the symptom experience of patients with benign prostatic hyperplasia and bladder fistula. Exploring the mediating effect of self-efficacy on the relationship between symptom experience and quality of life in patients with benign prostatic hyperplasia undergoing long-term indwelling cystostomy. METHODS: This study used a cross-sectional survey design. Patients with prostatic hyperplasia with cystostomy in the Urology department of General Hospital of Eastern Theater Command from January 2020 to February 2023 were selected, and relevant data were collected by IPSS, IIEF-5, HAMD, GSES, and quality of life score scale for statistical analysis. We then construct a structural equation model to evaluate the mediating effect of self-efficacy between symptom experience and quality of life. RESULTS: The average score of IPSS was (22.55±8.26) ; the average score of IIEF-5 was (10.54±4.10) ; the average score of HAMD was (6.82±2.35) ; the average score of self-efficacy was (20.80±8.65) ; and the average score of quality of life was (71.65±12.55) . Symptom experience was significantly negatively correlated with self-efficacy and quality of life( r=-0.496 , P<0.01;r=-0.518 , P<0.01) . Self-efficacy was significantly positively correlated with quality of life( r= 0.412,P<0.05). Symptom experience significantly negatively affected quality of life through self-efficacy (Effect = -0.218,P = 0.014) . CONCLUSION: Self-efficacy is positively correlated with the quality of life of patients with benign prostatic hyperplasia who have long-term indwelling cystostomy tube. Nursing staff can improve the level of self-efficacy of patients by implementing corresponding interventions.


Assuntos
Hiperplasia Prostática , Masculino , Humanos , Hiperplasia Prostática/cirurgia , Cistostomia , Autoeficácia , Qualidade de Vida , Estudos Transversais , Resultado do Tratamento
11.
Zhonghua Nan Ke Xue ; 29(9): 846-850, 2023 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-38639600

RESUMO

OBJECTIVE: To study the clinical therapeutic effect as well as drug effectiveness and safety of Shizi Sanhua decoction combined with Nuoyu in the treatment of oligozoospermia in men. METHODS: 102 patients with oligozoospermia diagnosed at Longhua Hospital of Shanghai University of Traditional Chinese Medicine from February 2022 to March 2023 were selected and randomly divided into 3 groups. The treatment group was treated with Shizi Sanhua Decoction + Nuoyu; the traditional Chinese medicine group was treated with Shizi Sanhua Decoction; and the Nuoyu nutrient group was treated with Nuoyu nutrient. A review assessment and record were made after one course of treatment (3 months). RESULTS: A total of 102 patients completed the trial due to the treatment process. There were 34 cases in each of the traditional Chinese medicine group, the Nuoyu nutrient group, and the treatment group. Clinical efficacy: total effective rate of 52.94% in the traditional Chinese medicine group; 58.82% in the Nuoyu nutrient group; 82.35% in the treatment group. The clinical efficacy of the treatment group was better than that of the traditional Chinese medicine group and the Nuoyu nutrient group (P<0.05), which was statistically significant. Semen routine: the treatment group was better than the traditional Chinese medicine group and Nuoyu nutrient group in improving the total number of sperm and sperm concentration. CONCLUSION: The semen concentration and forward sperm count of patients with oligozoospermia treated with Shizi Sanhua Decoction combined with Nuoyu improved more significantly, and the clinical efficacy was remarkable. And the clinical efficacy is not affected by age and disease duration. It can be popularized and applied as a treatment for oligozoospermia.


Assuntos
Medicamentos de Ervas Chinesas , Oligospermia , Humanos , Masculino , Medicamentos de Ervas Chinesas/uso terapêutico , Oligospermia/tratamento farmacológico , Oligospermia/induzido quimicamente , Sêmen , China , Medicina Tradicional Chinesa
12.
Mol Cancer ; 21(1): 25, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35057806

RESUMO

Primary lung cancer is one of the most common malignant tumors in China. Approximately 60% of lung cancer patients have distant metastasis at the initial diagnosis, so it is necessary to find new tumor markers for early diagnosis and individualized treatment. Tumor markers contribute to the early diagnosis of lung cancer and play important roles in early detection and treatment, as well as in precision medicine, efficacy monitoring, and prognosis prediction. The pathological diagnosis of lung cancer in small biopsy specimens determines whether there are tumor cells in the biopsy and tumor type. Because biopsy is traumatic and the compliance of patients with multiple biopsies is poor, liquid biopsy has become a hot research direction. Liquid biopsies are advantageous because they are nontraumatic, easy to obtain, reflect the overall state of the tumor, and allow for real-time monitoring. At present, liquid biopsies mainly include circulating tumor cells, circulating tumor DNA, exosomes, microRNA, circulating RNA, tumor platelets, and tumor endothelial cells. This review introduces the research progress and clinical application prospect of liquid biopsy technology for lung cancer.


Assuntos
Biomarcadores Tumorais , Biópsia Líquida , Neoplasias Pulmonares/diagnóstico , Animais , DNA Tumoral Circulante , Tomada de Decisão Clínica , Gerenciamento Clínico , Suscetibilidade a Doenças , Exossomos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Biópsia Líquida/métodos , Biópsia Líquida/normas , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/terapia , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Prognóstico
13.
Rapid Commun Mass Spectrom ; 36(2): e9220, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34741365

RESUMO

RATIONALE: Ion mobility spectrometry (IMS) is a powerful analytical tool extensively applied in numerous domains. However, there still exists the phenomenon of peaks overlapping in the analysis of isomers with similar structures due to the limited resolution of IMS. In this paper, a dynamic inertia weight particle swarm optimization (DIWPSO) algorithm combined with second-order differentiation is proposed to separate the IMS overlapping peaks efficiently and precisely. METHODS: It can identify the component number of overlapping peaks and limit those parameters (ion mobility, intensity, and full-width at half maximum of each single peak) of the peak model in a small range using second-order differentiation. Based on this, DIWPSO that has been set the best operating parameters is capable of accurately separating IMS overlapping peaks to identify the compound within a short time. RESULTS: A comparison between the performance of DIWPSO and the improved particle swarm optimization (IPSO) found that DIWPSO with separation errors less than 2.34% overall outperforms IPSO whose maximum error is up to 5.58%. Moreover, the running time of DIWPSO is 30-80 times less than that of IPSO, and DIWPSO exhibits stronger robustness. CONCLUSIONS: This method can automatically identify the component number of IMS overlapping peaks and resolve them with muticomponents and different overlapped degrees rapidly and accurately, which further improves the structural resolution of IMS.

14.
Phys Chem Chem Phys ; 24(48): 29667-29682, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36453140

RESUMO

Photoacoustic imaging techniques with gold nanoparticles as contrast agents have received a great deal of attention. The photoacoustic response of gold nanoparticles strongly depends on the far-field optical properties, which essentially depend on the dielectric constant of the material. The dielectric constant of gold not only varies with wavelength but is also affected by temperature. However, the effect of the temperature dependence of the dielectric constant on gold nanoparticles' photoacoustic response has not been fully investigated. In this work, the Drude-Lorentz model and Mie theory are used to calculate the dielectric constant and absorption efficiency of gold nanospheres in aqueous solution, respectively. Then, the finite element method is used to simulate the heat transfer process of gold nanospheres and surrounding water. Finally, the one-dimensional velocity-stress equation is solved by the finite-difference time-domain method to obtain the photoacoustic response of gold nanospheres. The results show that under the irradiation of a high-fluence nanosecond pulse laser, ignoring the temperature dependence of the dielectric constant will lead to large errors in the photothermal response and the nonlinear photoacoustic signals (it can even exceed 20% and 30%). The relative error of the photothermal and photoacoustic response caused by ignoring the temperature-dependent dielectric constant is determined from both the temperature dependence of absorption efficiency and the maximum temperature increase of gold nanospheres. This work provides a new perspective for the photothermal and photoacoustic effects of gold nanospheres, which is meaningful for the development of high-resolution photoacoustic detectors and nano/microscale temperature measurement techniques.

15.
Angew Chem Int Ed Engl ; 61(17): e202116934, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35148567

RESUMO

The integration of Fe dopant and interfacial FeOOH into Ni-MOFs [Fe-doped-(Ni-MOFs)/FeOOH] to construct Fe-O-Ni-O-Fe bonding is demonstrated and the origin of remarkable electrocatalytic performance of Ni-MOFs is elucidated. X-ray absorption/photoelectron spectroscopy and theoretical calculation results indicate that Fe-O-Ni-O-Fe bonding can facilitate the distorted coordinated structure of the Ni site with a short nickel-oxygen bond and low coordination number, and can promote the redistribution of Ni/Fe charge density to efficiently regulate the adsorption behavior of key intermediates with a near-optimal d-band center. Here the Fe-doped-(Ni-MOFs)/FeOOH with interfacial Fe-O-Ni-O-Fe bonding shows superior catalytic performance for OER with a low overpotential of 210 mV at 15 mA cm-2 and excellent stability with ≈3 % attenuation after a 120 h cycle test. This study provides a novel strategy to design high-performance Ni/Fe-based electrocatalysts for OER in alkaline media.

16.
Carcinogenesis ; 42(5): 762-771, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33758932

RESUMO

We examined the effect of microRNA-320b (miR-320b) on tumor growth and angiogenesis in lung cancer and also determined its downstream molecular mechanisms. Lung cancer tissues and adjacent non-cancerous tissues were collected from 66 patients with lung cancer. miR-320b expression was experimentally determined to be expressed at low level in cancer tissues. The results of gain-of-function experiments suggested that miR-320b overexpression suppressed cancer cell invasion, tube formation, tumor volume and angiogenesis in xenografted nude mice. Hepatocyte nuclear factor 4 gamma (HNF4G) was identified as a target of miR-320b based on in silico analysis. Dual-luciferase reporter gene assays further identified the binding relationship between HNF4G and miR-320b. Lung cancer tissues exhibited increased expression of HNF4G and insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2). Meanwhile, HNF4G knockdown suppressed IGF2BP2 expression, thereby repressing cancer cell invasion and tube formation. Furthermore, IGF2BP2 modified m6A to increase the expression of thymidine kinase 1 (TK1), thus promoting angiogenesis. In nude mice, restoration of TK1 reversed the suppressive effect of miR-320b overexpression on tumor growth rate and CD31 expression. In conclusion, miR-320b suppresses lung cancer growth and angiogenesis by inhibiting HNF4G, IGF2BP2 and TK1.


Assuntos
Fator 4 Nuclear de Hepatócito/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Neovascularização Patológica/genética , Proteínas de Ligação a RNA/genética , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Xenoenxertos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Neovascularização Patológica/patologia , Transdução de Sinais/genética
17.
J Cell Mol Med ; 25(8): 3699-3713, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33621425

RESUMO

MicroRNA-24-3p (miR-24-3p) has been implicated as a key promoter of chemotherapy resistance in numerous cancers. Meanwhile, cancer-associated fibroblasts (CAFs) can secret exosomes to transfer miRNAs, which mediate tumour development. However, little is known regarding the molecular mechanism of CAF-derived exosomal miR-24-3p in colon cancer (CC). Hence, this study intended to characterize the functional relevance of CAF-derived exosomal miR-24-3p in CC cell resistance to methotrexate (MTX). We identified differentially expressed HEPH, CDX2 and miR-24-3p in CC through bioinformatics analyses, and validated their expression in CC tissues and cells. The relationship among HEPH, CDX2 and miR-24-3p was verified using ChIP and dual-luciferase reporter gene assays. Exosomes were isolated from miR-24-3p inhibitor-treated CAFs (CAFs-exo/miR-24-3p inhibitor), which were used in combination with gain-of-function and loss-of-function experiments and MTX treatment. CCK-8, flow cytometry and colony formation assays were conducted to determine cell viability, apoptosis and colony formation, respectively. Based on the findings, CC tissues and cells presented with high expression of miR-24-3p and low expression of HEPH and CDX2. CDX2 was a target gene of miR-24-3p and could up-regulate HEPH. Under MTX treatment, overexpressed CDX2 or HEPH and down-regulated miR-24-3p reduced cell viability and colony formation and elevated cell apoptosis. Furthermore, miR-24-3p was transferred into CC cells via CAF-derived exosomes. CAF-derived exosomal miR-24-3p inhibitor diminished cell viability and colony formation and increased cell apoptosis in vitro and inhibited tumour growth in vivo under MTX treatment. Altogether, CAF-derived exosomal miR-24-3p accelerated resistance of CC cells to MTX by down-regulating CDX2/HEPH axis.


Assuntos
Fator de Transcrição CDX2/metabolismo , Neoplasias do Colo/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Exossomos/genética , Proteínas de Membrana/metabolismo , Metotrexato/farmacologia , MicroRNAs/genética , Idoso , Animais , Antimetabólitos Antineoplásicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Fator de Transcrição CDX2/genética , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Proliferação de Células , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
18.
J Cell Mol Med ; 25(8): 4040-4052, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33621431

RESUMO

Hepatocellular cancer (HCC) has been reported to belong to one of the highly vascularized solid tumours accompanied with angiogenesis of human umbilical vein endothelial cells (HUVECs). KDM5A, an attractive drug target, plays a critical role in diverse physiological processes. Thus, this study aims to investigate its role in angiogenesis and underlying mechanisms in HCC. ChIP-qPCR was utilized to validate enrichment of H3K4me3 and KDM5A on the promotor region of miR-433, while dual luciferase assay was carried out to confirm the targeting relationship between miR-433 and FXYD3. Scratch assay, transwell assay, Edu assay, pseudo-tube formation assay and mice with xenografted tumours were conducted to investigate the physiological function of KDM5A-miR-433-FXYD3-PI3K-AKT axis in the progression of HCC after loss- and gain-function assays. KDM5A p-p85 and p-AKT were highly expressed but miR-433 was down-regulated in HCC tissues and cell lines. Depletion of KDM5A led to reduced migrative, invasive and proliferative capacities in HCC cells, including growth and a lowered HUVEC angiogenic capacity in vitro. Furthermore, KDM5A suppressed the expression of miR-433 by demethylating H3K4me3 on its promoterregion. miR-433 negatively targeted FXYD3. Depleting miR-433 or re-expressing FXYD3 restores the reduced migrative, invasive and proliferative capacities, and lowers the HUVEC angiogenic capacity caused by silencing KDM5A. Therefore, KDM5A silencing significantly suppresses HCC tumorigenesis in vivo, accompanied with down-regulated miR-433 and up-regulated FXYD3-PI3K-AKT axis in tumour tissues. Lastly, KDM5A activates the FXYD3-PI3K-AKT axis to enhance angiogenesis in HCC by suppressing miR-433.


Assuntos
Carcinoma Hepatocelular/patologia , Proteínas de Membrana/antagonistas & inibidores , MicroRNAs/genética , Proteínas de Neoplasias/antagonistas & inibidores , Neovascularização Patológica/prevenção & controle , Fosfatidilinositol 3-Quinases/química , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteína 2 de Ligação ao Retinoblastoma/antagonistas & inibidores , Idoso , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína 2 de Ligação ao Retinoblastoma/genética , Proteína 2 de Ligação ao Retinoblastoma/metabolismo , Taxa de Sobrevida , Células Tumorais Cultivadas
19.
J Transl Med ; 19(1): 400, 2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34551785

RESUMO

BACKGROUND: Cancer stem cells (CSCs) are key regulators in the processes of tumor initiation, progression, and recurrence. The mechanism that maintains their stemness remains enigmatic, although the role of several long noncoding RNAs (lncRNAs) has been highlighted in the pancreatic cancer stem cells (PCSCs). In this study, we first established that PCSCs overexpressing lncRNA NORAD, and then investigated the effects of NORAD on the maintenance of PCSC stemness. METHODS: Expression of lncRNA NORAD, miR-202-5p and ANP32E in PC tissues and cell lines was quantified after RNA isolation. Dual-luciferase reporter assay, RNA pull-down and RIP assays were performed to verify the interactions among NORAD, miR-202-5p and ANP32E. We then carried out gain- and loss-of function of miR-202-5p, ANP32E and NORAD in PANC-1 cell line, followed by measurement of the aldehyde dehydrogenase activity, cell viability, apoptosis, cell cycle distribution, colony formation, self-renewal ability and tumorigenicity of PC cells. RESULTS: LncRNA NORAD and ANP32E were upregulated in PC tissues and cells, whereas the miR-202-5p level was down-regulated. LncRNA NORAD competitively bound to miR-202-5p, and promoted the expression of the miR-202-5p target gene ANP32E thereby promoting PC cell viability, proliferation, and self-renewal ability in vitro, as well as facilitating tumorigenesis of PCSCs in vivo. CONCLUSION: Overall, lncRNA NORAD upregulates ANP32E expression by competitively binding to miR-202-5, which accelerates the proliferation and self-renewal of PCSCs.


Assuntos
MicroRNAs , Neoplasias Pancreáticas , RNA Longo não Codificante , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Chaperonas Moleculares , Recidiva Local de Neoplasia , Neoplasias Pancreáticas/genética , RNA Longo não Codificante/genética
20.
Environ Monit Assess ; 193(6): 332, 2021 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-33966117

RESUMO

Methionine is one of the many amino acids in the soil. In order to study the role of methionine in acidic forest soil, the effect of methionine (Met) was compared with control together with addition of ammonium (Met + A), nitrite (Met + N), and glucose (Met + C) under 60% or 90% water holding capacity (WHC), because ammonium and nitrite are important factors in nitrification, and glucose affect the heterotrophic nitrification and nitrogen immobilization. We found that methionine addition significantly reduced NO3- concentration in acidic forest soil. Compared to Met, Met + A and Met + N treatments non-significantly enhanced nitrification; however, Met + C treatment decreased NH4+ concentration which suggested that soil autotrophic and heterotrophic nitrification were limited in the presence of methionine at 60% WHC. Further, our findings of 15N-labeled treatment showed the impact and priming effect of methionine was negative for NO3- concentration and positive for N2O emission, which were observed mainly from the soil N source rather than methionine. At 90% WHC, Met + C treatment significantly lessened concentrations of NH4+ and NO3-, nonetheless improved N2O compared to Met treatment. Therefore, besides the denitrification and dissimilatory NO3- reduction to ammonia, the immobilization might be the key factor to explain this decrease in NO3- concentration at 90% WHC, while these processes were induced with the C addition. This study indicated that the positive role of amino acids in soil N cycling might be overrated.


Assuntos
Compostos de Amônio , Solo , Desnitrificação , Monitoramento Ambiental , Glucose , Metionina , Nitrificação , Nitritos , Nitrogênio
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