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1.
J Phys Chem A ; 128(2): 449-455, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38174707

RESUMO

Nitrogen (N2) activation at room temperature has long been a great challenge. Therefore, the rational design of reactive species to adsorb N2, which is a prerequisite for cleavage of the strong N≡N triple bond in industrial and biological processes, is highly desirable and meaningful. Herein, the N2 adsorption process is controlled by regulating the types and numbers of organic ligands, and the organic ligands are produced through the reactions of Ir+ with methane and ethane. CH4 molecules dissociate on the Ir+ cations to form Ir(CH2)1,2+. The reaction of Ir+ with C2H6 can generate HIrC2H3+, which is different from the structure of Ir(CH2)2+ obtained from Ir+/CH4. The reactivity order of N2 adsorption is Ir(CH2)2+ > HIrC2H3+ ≫ HIrCH+ ≈ Ir+ (almost inert under similar reaction conditions), indicating that different organic ligand structures affect reactivity dramatically. The main reason for this interesting reactivity difference is that the lowest unoccupied molecular orbital (LUMO) level of Ir(CH2)2+ is much closer to the highest occupied molecular orbital (HOMO) level of N2 than those of the other three systems. This study provides new insights into the adsorption of N2 on metal-organic ligand species, in which the organic ligand dominates the reactivity, and it discovers new clues in designing effective transition metal carbine species for N2 activation.

2.
Inorg Chem ; 62(15): 6102-6108, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37021782

RESUMO

The direct coupling of dinitrogen (N2) and oxygen (O2) to produce value-added chemicals such as nitric acid (HNO3) at room temperature is fascinating but quite challenging because of the inertness of N2 molecules. Herein, an interesting reaction pathway is proposed for a direct conversion of N2 and O2 mediated by all-metal Y3+ cations. This reaction pattern begins with the N≡N triple bond cleavage by Y3+ to generate a dinitride cation Y2N2+, and the electrons that lead to N2 activation in this process mainly originate from Y atoms. In the following consecutive reactions with two O2 molecules, the electrons stored in the N atoms are gradually released to reduce O2 through re-formation and re-fracture of the N-N bonds, with concomitant release of two NO molecules. Therefore, the reversible N-N bond switching acts as an efficient electron reservoir to drive the oxidation of the reduced N atoms, leading to the formation of NO molecules. This method of producing NO by direct coupling N2 and O2 molecules, which is the reversible N-N bond switching, may provide a new strategy for the direct synthesis of HNO3, etc.

3.
J Phys Chem A ; 127(14): 3082-3087, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37014705

RESUMO

Compared with transition metals, nonmetallic elements have always been considered to have low reactivity toward carbon dioxide. However, in recent years, main-group compounds such as boron-based species have gradually attracted increasing attention due to their prospective applications in different kinds of reactions. Herein, we report that metal-free anions B2O2- can promote two CO2 reductions, producing the oxygen-rich product B2O4-. In most of the reported CO2 reduction reactions mediated by transition-metal-containing clusters, transition metals usually provide electrons for the activation of CO2; one oxygen atom in CO2 is transferred to metal atoms, and CO is released from the metal atoms. In sharp contrast, B atoms are electron donors in the current systems and the formed CO is liberated directly from the activated CO2 unit. The synthesis of novel-metal-free gas-phase clusters and investigation of their reactivity toward carbon dioxide as well as reaction mechanisms can provide a fundamental basis in practice for the rational design of active sites on metal-free catalysts.

4.
Appl Opt ; 62(28): 7367-7372, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855504

RESUMO

Non-line-of-sight (NLOS) optical camera communications (OCC) exhibit greater link availability and mobility than line-of-sight links, which are more susceptible to blocking and shadowing. In this work, we propose an NLOS OCC system, where the data signal is mapped into color pulse width modulation (CPWM) symbols prior to transmission using a red-, green-, and blue light-emitting diode. A convolutional-neural-network-based receiver is used to demodulate the CPWM signal. Based on experimental results, the proposed scheme effectively mitigates the effects of diffuse reflection induced intersymbol interference, resulting in an increased data transmission rate to 7.2 kbps over a link span of more than 2 m, which is typical for indoor applications.

5.
Phys Chem Chem Phys ; 24(23): 14333-14338, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35642691

RESUMO

The activation and functionalization of dinitrogen with carbon dioxide into useful chemicals containing C-N bonds are significant research projects but highly challenging. Herein, we report that N2 molecules are dissociated by heterobimetallic CuNb- anions assisted by surface plasma radiation, leading to the formation of CuNbN2- anions; the CuNbN2- anions can further react with CO2 to generate products NCO- with one C-N bond and NbO2NCN- with two C-N bonds under thermal collision conditions. For the activation of dinitrogen, the plasma atmosphere is conducive to the dissociation of the NN bond, which renders the coupling reactions of N2 and CO2 molecules easier to proceed. This is the first report of coupling of N2 and CO2 to generate C-N bonds by making good use of the plasma effect to assist in the activation of N2 molecules. This new strategy with the assistance of plasma provides a practicable route to construct C-N bonds by directly using N2 and CO2 at room temperature.

6.
J Phys Chem A ; 126(9): 1511-1517, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35226501

RESUMO

Alkali atoms are usually used as promoters to significantly increase the catalytic activity of transition-metal catalysts in a wide range of reactions such as dinitrogen conversion reactions. However, the role of alkali metal atoms remains controversial. Herein, a series of quaternary cluster anions containing lithium atoms Nb2LiNO1-4- have been synthesized and reacted with N2 at room temperature. The detailed experimental and theoretical investigations indicate that Nb2LiNO- is capable to cleave the N≡N bond and the Li atoms in Nb2LiNO1,2- act as electron donors in the N2 reduction reaction. With the increase in the number of oxygen atoms, the reactivity toward N2 is reduced from adsorption via a side-on end-on mode in Nb2LiNO2- to the inertness of Nb2LiNO4-. In Nb2LiNO3,4- anions, the Li atoms are bonded with oxygen atoms, acting as structural units to stabilize structures. Therefore, the roles of alkali atoms are able to change with different chemical environments of active sites. For the first time, we reveal how the number of ligands (oxygen atoms herein) can be used to finely regulate the reactivity toward N2.

7.
Int J Mol Sci ; 23(13)2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35805983

RESUMO

The adsorption of atmospheric dinitrogen (N2) on transition metal sites is an important topic in chemistry, which is regarded as the prerequisite for the activation of robust N≡N bonds in biological and industrial fields. Metal hydride bonds play an important part in the adsorption of N2, while the role of hydrogen has not been comprehensively studied. Herein, we report the N2 adsorption on the well-defined Y2C4H0,1- cluster anions under mild conditions by using mass spectrometry and density functional theory calculations. The mass spectrometry results reveal that the reactivity of N2 adsorption on Y2C4H- is 50 times higher than that on Y2C4- clusters. Further analysis reveals the important role of the H atom: (1) the presence of the H atom modifies the charge distribution of the Y2C4H- anion; (2) the approach of N2 to Y2C4H- is more favorable kinetically compared to that to Y2C4-; and (3) a natural charge analysis shows that two Y atoms and one Y atom are the major electron donors in the Y2C4- and Y2C4H- anion clusters, respectively. This work provides new clues to the rational design of TM-based catalysts by efficiently doping hydrogen atoms to modulate the reactivity towards N2.


Assuntos
Hidrogênio , Modelos Teóricos , Adsorção , Ânions/química , Hidrogênio/química , Temperatura
8.
J Cell Mol Med ; 25(23): 10980-10989, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34773364

RESUMO

Deubiquitinating enzyme OTU domain-containing ubiquitin aldehyde-binding proteins 1 (OTUB1) has been shown to have an essential role in multiple carcinomas. However, the function of OTUB1 in papillary thyroid cancer (PTC) and the underlying mechanisms regulating PTC cells proliferation remain poorly understood. In this study, OTUB1 was significantly upregulated in papillary thyroid carcinoma tissues and cells. Through in vitro and in vivo experiments, knockdown of OTUB1 suppressed PTC cells growth whereas OTUB1 overexpression enhanced the proliferation ability of PTC cells. Moreover, the eyes absent homologue 1 (EYA1) was recognized as a potential target of OTUB1 through mass spectrometry analysis, and we further verified that EYA1 protein level was positively correlated with OTUB1 expression in PTC cells and clinical samples. Mechanistically, OTUB1 could interact with EYA1 directly and deubiquitinate EYA1 to stabilize it. At last, EYA1 was found to play an essential role in OTUB1-derived PTC cells growth. Overall, our investigation reveals that OTUB1 is a previously unrecognized oncogenic factor in PTC cells proliferation and suggests that OTUB1 might be a novel therapeutic target in PTC.


Assuntos
Proliferação de Células/genética , Enzimas Desubiquitinantes/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Nucleares/genética , Proteínas Tirosina Fosfatases/genética , Neoplasias da Glândula Tireoide/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Oncogenes/genética , Transdução de Sinais/genética , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Regulação para Cima/genética
9.
Phys Chem Chem Phys ; 23(22): 12592-12599, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34047332

RESUMO

Cleavage of all C-H bonds in two methane molecules by gas-phase cluster ions at room temperature is a challenging task. Herein, mass spectrometry and quantum chemical calculations have been used to identify one single metal boride cluster anions NbB4- that can activate eight C-H bonds in two methane molecules and release one H2 molecule each time under thermal collision conditions. In these consecutive reactions, the loaded Nb atoms and the support B4 units play different roles but act synergistically to activate CH4, which is responsible for the interesting reactivity of NbB4-. Moreover, there are some mechanistic differences in these two reactions, including the mechanisms for the first C-H bond activation steps, dihydrogen desorption sites, and major electron donors. This study shows that non-noble metal boride species are reactive enough to facilitate thermal C-H bond cleavages, and boron-based materials may be one kind of potential support material facilitating surface hydrogen transport.

10.
Anal Chem ; 92(6): 4583-4591, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32056429

RESUMO

The continuous detection of glucose is significant for revealing its role in neuron protection and for diagnosis of various diseases. In this study, for the first time, a nonenzymatic online optical detection platform (OODP) for glucose measurement in rat brain utilizing the tandem enzyme activity of V2O5 nanobelts is developed. V2O5 nanobelts were synthesized via a facile solvothermal strategy, and for the first time it is found that the V2O5 nanobelts possess dual enzyme-like activity, i.e., glucose oxidase (GOx)-like and peroxidase-like activity, and can act as a "tandem nanozyme". To investigate the mechanisms of the GOx-like property, we built an adsorption model, and the RPBE density functional calculations indicate that the glucose molecule can be adsorbed on the V2O5 plane. Based on the ability of V2O5 nanobelts to mimick tandem enzymes, a nonenzymatic online optical detection platform (OODP) for the continuous monitoring of glucose in rat brain was designed, which exhibits excellent stability, high selectivity, and a wide linear detection range from 0.2 to 5 mM and records cerebral glucose alterations in the calm/ischemia model. This facile but reliable nonenzymatic online optical glucose measurement compares favorably with natural enzyme-based online electrochemical glucose analytical systems, and its ready adoption by physiologists and pathologists will facilitate the understanding of brain function and the pathogenesis of diabetes.


Assuntos
Encéfalo , Glucose/análise , Nanocompostos/química , Compostos de Vanádio/química , Animais , Dispositivos Lab-On-A-Chip , Luz , Tamanho da Partícula , Ratos , Propriedades de Superfície , Compostos de Vanádio/síntese química
11.
Phys Chem Chem Phys ; 22(46): 27357-27363, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33231227

RESUMO

The heterogeneous oxidation of isoprene (C5H8) by metal-oxide particles, such as the typical mineral aerosols TiO2, plays an important role in the isoprene atmospheric chemistry. However, the underlying mechanism of C5H8 oxidation remains elusive owing to the complexities of aerosol surfaces and reaction channels. Herein, we report the gas-phase reactions of TixOy+ (x = 1-7, y = 1-14) cations with isoprene by using mass spectrometry and density functional theory (DFT) calculations. Five types of reaction channels were observed: association, hydrogen atom transfer (HAT), C-C bond cleavage, combined oxygen atom transfer (OAT) and HAT and combined OAT and C-C bond cleavage. It is noteworthy that formaldehyde is known as the major oxidation product of isoprene/hydroxyl radicals in the atmosphere. In addition, CO has not been observed in the reactions of isoprene with gas-phase ions. Therefore, the reaction mechanisms of CH2O and CO generation observed in Ti2O5+/C5H8 and Ti4O8+/C5H8 systems were further investigated by DFT calculations, and the calculated results are in agreement with the experimental observations. In these two reactions, both Ti and O atoms can be the adsorption sites for C5H8. The reaction channels and mechanistic information gained in these gas-phase model reactions may offer fundamental insights relevant to the corresponding oxidation processes over titanium oxide aerosols in the atmosphere.

12.
Anal Chem ; 90(12): 7158-7163, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29799730

RESUMO

We developed a simple and environmentally friendly ultraviolet (UV)-irradiation-assisted technique to fabricate a stretchable, nanostructured gold film as a flexible electrode for the detection of NO release. The flexible gold film endows the electrode with desirable electrochemical stability against mechanical deformation, including bending to different curvatures and bearing repeated bending circumstances (200 times). The flexible nanostructured gold electrodes can catalyze NO oxidation at 0.85 V (as opposed to Ag/AgCl) and detect NO within a wide linearity in the range of 10 nM to 1.295 µM. Its excellent NO-sensing ability and its stretchability together with its biocompatibility allows the electrode to electrochemically monitor NO release from mechanically sensitive HUVECs in both their unstretched and stretched states. This result paves the way for an effective and easily accessible platform for designing stretchable and flexible electrodes and opens more opportunities for sensing chemical-signal molecules released from cells or other biological samples during mechanical stimulation.


Assuntos
Ouro/química , Células Endoteliais da Veia Umbilical Humana/química , Nanoestruturas/química , Óxido Nítrico/análise , Raios Ultravioleta , Eletrodos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Óxido Nítrico/metabolismo , Tamanho da Partícula , Propriedades de Superfície
13.
Mikrochim Acta ; 185(2): 131, 2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-29594579

RESUMO

The authors report that cobalt oxyhydroxide (CoOOH) nanoflakes possess intrinsic oxidizing ability to directly oxidize 3,3',5,5'-tetramethylbenzidine (TMB) to form a blue colored product (oxTMB) even in the absence of H2O2 and oxygen. In the presence of ascorbic acid (AA), less of the blue product is formed because AA reduces oxTMB. These findings constitute a new scheme for colorimetric detection of AA. Absorbance, best measured at 652 nm, linearly drops in the 10 nM to 1 µM AA concentration range, and the limit of detection is 5 nM (at an S/N ratio of 3). The reaction is complete within <5 s and highly selective. A strip test has been designed for fast and on-spot visual detection of AA. The method was applied to the direct estimation of AA in the microdialysate of brain, and also in soft drink samples. The strip test is considered to be a promising tool for the rapid screening of AA in brain and commercial samples. Graphic abstract Schematic of the CoOOH-TMB colorimetric system that exhibits a high selectivity for ascorbic acid (AA). A strip test has been designed for fast and on-spot visual detection of AA.

14.
BJS Open ; 8(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38284398

RESUMO

BACKGROUND: A paucity of evidence exists regarding the optimal management for abdominal aortic graft infection. The aim of this paper was to assess short- and long-term outcomes following different surgical options in aortic graft infection patients. METHODS: Medline, Embase and the Cochrane Library were searched from inception to February 2023. Network meta-analysis was performed using a frequentist method. Patients were divided into four treatment groups: complete graft removal with in situ repair, complete graft removal with extra-anatomic repair, partial graft removal with in situ repair and partial graft removal with extra-anatomic repair. The mortality rate at 30-days and 1-year was the primary outcome. Secondary outcomes were longer-term mortality rate, primary patency and reinfections. For included RCTs, the Cochrane risk-of-bias tool was utilized to assess the risk of bias. The methodological quality of cohort studies was evaluated using the Newcastle-Ottawa scale. RESULTS: Among 4559 retrieved studies, 22 studies with 1118 patients (11 multi-arm and 11 single-arm studies) were included. Patients received complete graft removal with in situ repair (N = 852), partial graft removal with in situ repair (N = 36), complete graft removal with extra-anatomic repair (N = 228) and partial graft removal with extra-anatomic repair (N = 2). Both network meta-analysis results and pooled results of multi- and single-arm cohorts indicated that partial graft removal with in situ repair has the lowest 30-day and 1-year mortality rates (0% and 6.1% respectively), followed by complete graft removal with in situ repair (11.9% and 23.8% respectively) and complete graft removal with extra-anatomic repair (16.6% and 41.4% respectively). In addition, complete graft removal with in situ repair had a lower 3-year (complete graft removal with in situ repair versus complete graft removal with extra-anatomic repair: 32.1% versus 90%) and 5-year (complete graft removal with in situ repair versus complete graft removal with extra-anatomic repair: 45.6% versus 67.9%) mortality rate when compared with complete graft removal with extra-anatomic repair. Patients in the complete graft removal with in situ repair group had the lowest reinfections (8%), followed by partial graft removal with in situ repair (9.3%) and complete graft removal with extra-anatomic repair (22.4%). CONCLUSION: Partial graft removal with in situ repair was associated with lower 30-day and 1-year mortality rates when compared with complete graft removal with in situ repair and complete graft removal with extra-anatomic repair. Partial graft removal with in situ repair might be a feasible treatment for specific aortic graft infection patients.


Assuntos
Implante de Prótese Vascular , Prótese Vascular , Humanos , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/métodos , Reinfecção , Metanálise em Rede , Complicações Pós-Operatórias
15.
Aging (Albany NY) ; 16(8): 6954-6989, 2024 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-38613802

RESUMO

BACKGROUND: Glioma, a highly invasive and deadly form of human neoplasm, presents a pressing need for the exploration of potential therapeutic targets. While the lysosomal protein transmembrane 4A (LATPM4A) has been identified as a risk factor in pancreatic cancer patients, its role in glioma remains unexplored. METHODS: The analysis of differentially expressed genes (DEG) was conducted from The Cancer Genome Atlas (TCGA) glioma dataset and the Genotype Tissue Expression (GTEx) dataset. Through weighted gene co-expression network analysis (WGCNA), the key glioma-related genes were identified. Among these, by using Kaplan-Meier (KM) analysis and univariate/multivariate COX methods, LAPTM4A emerged as the most influential gene. Moreover, the bioinformatics methods and experimental verification were employed to analyze its relationships with diagnosis, clinical parameters, epithelial-mesenchymal transition (EMT), metastasis, immune cell infiltration, immunotherapy, drug sensitivity, and ceRNA network. RESULTS: Our findings revealed that LAPTM4A was up-regulated in gliomas and was associated with clinicopathological features, leading to poor prognosis. Furthermore, functional enrichment analysis demonstrated that LATPM4A played a role in the immune system and cancer progression. In vitro experiments indicated that LAPTM4A may influence metastasis through the EMT pathway in glioma. Additionally, we found that LAPTM4A was associated with the tumor microenvironment (TME) and immunotherapy. Notably, drug sensitivity analysis revealed that patients with high LAPTM4A expression were sensitive to doxorubicin, which contributed to a reduction in LAPTM4A expression. Finally, we uncovered the FGD5-AS1-hsa-miR-103a-3p-LAPTM4A axis as a facilitator of glioma progression. CONCLUSIONS: In conclusion, our study identifies LATPM4A as a promising biomarker for prognosis and immune characteristics in glioma.


Assuntos
Biomarcadores Tumorais , Neoplasias Encefálicas , Biologia Computacional , Glioma , Proteínas de Membrana , Feminino , Humanos , Masculino , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Glioma/genética , Glioma/patologia , Glioma/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Prognóstico
16.
J Phys Chem Lett ; 14(34): 7597-7602, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37603698

RESUMO

Dinitrogen (N2) activation and its chemical transformations are some of the most challenging topics in chemistry. Herein, we report that heteronuclear metal anions AuNbBO- can mediate the direct coupling of N2 and O2 to generate NO molecules. N2 first forms the nondissociative adsorption product AuNbBON2- on AuNbBO-. In the following reactions with two O2 molecules, two NO molecules are gradually released, with the formation of AuNbBO2N- and AuNbBO3-. In the reaction with the first O2, the generated nitrene radical (N••-) originating from the dissociated N2, induces the activation of O2. Subsequently, the second O2 is anchored and forms a superoxide radical (O2•-); this radical attacks the other N atom to form an N-O bond, releasing the second NO. The N••- and O2•- radicals play key roles in the reactions. The mechanism adopted in this direct oxidation of N2 by O2 to NO can be labeled as a Zeldovich-like mechanism.

17.
Aging (Albany NY) ; 15(13): 6179-6211, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37400985

RESUMO

Hepatocellular carcinoma (HCC) is an ongoing challenge worldwide. Zinc finger protein 765 (ZNF765) is an important zinc finger protein that is related to the permeability of the blood-tumor barrier. However, the role of ZNF765 in HCC is unclear. This study evaluated the expression of ZNF765 in hepatocellular carcinoma and the impact of its expression on patient prognosis based on The Cancer Genome Atlas (TCGA). Immunohistochemical assays (IHC) were used to examine protein expression. Besides, a colony formation assay was used to examine cell viability. We also explored the relationship between ZNF765 and chemokines in the HCCLM3 cells by qRT-PCR. Moreover, we examined the effect of ZNF765 on cell resistance by measurement of the maximum half-inhibitory concentration. Our research revealed that ZNF765 expression in HCC samples was higher than that in normal samples, whose upregulation was not conducive to the prognosis. The results of GO, KEGG, and GSEA showed that ZNF765 was associated with the cell cycle and immune infiltration. Furthermore, we confirmed that the expression of ZNF765 had a strong connection with the infiltration level of various immune cells, such as B cells, CD4+ T cells, macrophages, and neutrophils. In addition, we found that ZNF765 was associated with m6A modification, which may affect the progression of HCC. Finally, drug sensitivity testing found that patients with HCC were sensitive to 20 drugs when they expressed high levels of ZNF765. In conclusion, ZNF765 may be a prognostic biomarker related to cell cycle, immune infiltration, m6A modification, and drug sensitivity for hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Prognóstico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Ciclo Celular , Biomarcadores
18.
Aging (Albany NY) ; 15(7): 2631-2666, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-37059586

RESUMO

Hepatocellular carcinoma (HCC) is the most common subtype of liver cancer, with a high morbidity and low survival rate. Rho GTPase activating protein 39 (ARHGAP39) is a crucial activating protein of Rho GTPases, a novel target in cancer therapy, and it was identified as a hub gene for gastric cancer. However, the expression and role of ARHGAP39 in hepatocellular carcinoma remain unclear. Accordingly, the cancer genome atlas (TCGA) data were used to analyze the expression and clinical value of ARHGAP39 in hepatocellular carcinoma. Further, the LinkedOmics tool suggested functional enrichment pathways for ARHGAP39. To investigate in depth the possible role of ARHGAP39 on immune infiltration, we analyzed the relationship between ARHGAP39 and chemokines in HCCLM3 cells. Finally, the GSCA website was used to explore drug resistance in patients with high ARHGAP39 expression. Studies have shown that ARHGAP39 is highly expressed in hepatocellular carcinoma and relevant to clinicopathological features. In addition, the overexpression of ARHGAP39 leads to a poor prognosis. Besides, co-expressed genes and enrichment analysis showed a correlation with the cell cycle. Notably, ARHGAP39 may worsen the survival of hepatocellular carcinoma patients by increasing the level of immune infiltration through chemokines. Moreover, N6-methyladenosine (m6A) modification-related factors and drug sensitivity were also found to be associated with ARHGAP39. In brief, ARHGAP39 is a promising prognostic factor for hepatocellular carcinoma patients that is closely related to cell cycle, immune infiltration, m6A modification, and drug resistance.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Biomarcadores , Carcinoma Hepatocelular/genética , Ciclo Celular , Neoplasias Hepáticas/genética , Prognóstico
19.
Aging (Albany NY) ; 15(8): 2937-2969, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-37074800

RESUMO

PURPOSE: Hepatocellular carcinoma (HCC) is a prevalent tumor with high morbidity, and an unfavourable prognosis. FARSB is an aminoacyl tRNA synthase, and plays a key role in protein synthesis in cells. Furthermore, previous reports have indicated that FARSB is overexpressed in gastric tumor tissues and is associated with a poor prognosis and tumorigenesis. However, the function of FARSB in HCC has not been studied. RESULTS: The results showed that FARSB mRNA and protein levels were upregulated in HCC and were closely related to many clinicopathological characteristics. Besides, according to multivariate Cox analysis, high FARSB expression was linked with a shorter survival time in HCC and may be an independent prognostic factor. In addition, the FARSB promoter methylation level was negatively associated with the expression of FARSB. Furthermore, enrichment analysis showed that FARSB was related to the cell cycle. And TIMER analysis revealed that the FARSB expression was closely linked to tumor purity and immune cell infiltration. The TCGA and ICGC data analysis suggested that FARSB expression is greatly related to m6A modifier related genes. Potential FARSB-related ceRNA regulatory networks were also constructed. What's more, based on the FARSB-protein interaction network, molecular docking models of FARSB and RPLP1 were constructed. Finally, drug susceptibility testing revealed that FARSB was susceptible to 38 different drugs or small molecules. CONCLUSIONS: FARSB can serve as a prognostic biomarker for HCC and provide clues about immune infiltration, and m6A modification.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Mycobacterium tuberculosis , Humanos , Carcinoma Hepatocelular/genética , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Prognóstico , Neoplasias Hepáticas/genética , Biomarcadores
20.
J Phys Chem Lett ; 13(18): 4058-4063, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35499311

RESUMO

Nitrogen fixation and hydrogenation are important issues in chemistry and industry. Herein, we used mass spectrometry and quantum chemical calculations to identify the quaternary AuNbBO- anions that can efficiently activate N2 and H2 to form imido (or amido) units in the products AuNbBON2H2- under thermal collision conditions. In these reactions, Nb and B atoms work in synergy to dissociate N2 and the Au atom acts as a reducing agent, which facilitates the removal of one activated N atom for the following hydrogenation process; generation of three-centered, two-electron bonds facilitates N2 activation and N transformation. This study shows that the noble metal-assisted early transition metal boronyl cluster is highly reactive to facilitate thermal N-N and H-H bond cleavage, and NH (or NH2) and NBO units, which are important intermediates in N2 hydrogenation reactions, are formed. These findings may provide insight into the design of new catalysts for the synthesis of NH3 from N2 and H2.

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