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1.
Sci Rep ; 14(1): 18183, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107359

RESUMO

To study the effect of polycrystalline 3C-SiC rough friction surface on the mechanism of subsurface brittleness during nanocrystalline grinding. Initial grinding models of polycrystalline 3C-SiC and diamond abrasive grains on rough friction surfaces are developed using molecular dynamics methods and the Voronoi method for constructing polycrystalline abrasive grains. The processing mechanism of 3C-SiC is analyzed by post-processing methods such as dislocation defect analysis, atomic arrangement analysis and stress analysis. At 2.6 nm, "stress concentration" occurs between the abrasive particles and the workpiece, forming irregular force shapes. The larger the grain size, the smaller the crystal hardness, the greater the possibility of crystal fracture, and it is obvious in the crystal of larger grains. At 8 nm, the crystal breaks and creates vacancies. The roughness of the polycrystalline 3C-SiC friction surface and the cross-cutting mechanism between grains with grain boundaries are found to be effective in ameliorating the damage in the subsurface layer.

2.
Oncogene ; 43(33): 2504-2516, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38969770

RESUMO

Despite significantly improved clinical outcomes in EGFR-mutant lung adenocarcinoma, all patients develop acquired resistance and malignancy on the treatment of EGFR tyrosine kinase inhibitors (EGFR-TKIs). Understanding the resistance mechanisms is crucial to uncover novel therapeutic targets to improve the efficacy of EGFR-TKI treatment. Here, integrated analysis using RNA-Seq and shRNAs metabolic screening reveals glutathione S-transferase omega 1 (GSTO1) as one of the key metabolic enzymes that is required for EGFR-TKIs resistance in lung adenocarcinoma cells. Aberrant upregulation of GSTO1 confers EGFR-TKIs resistance and tumor metastasis in vitro and in vivo dependent on its active-site cysteine 32 (C32). Pharmacological inhibition or knockdown of GSTO1 restores sensitivity to EGFR-TKIs and synergistically enhances tumoricidal effects. Importantly, nucleophosmin 1 (NPM1) cysteine 104 is deglutathionylated by GSTO1 through its active C32 site, which leads to activation of the AKT/NF-κB signaling pathway. In addition, clinical data illustrates that GSTO1 level is positively correlated with NPM1 level, NF-κB-mediated transcriptions and progression of human lung adenocarcinoma. Overall, our study highlights a novel mechanism of GSTO1 mediating EGFR-TKIs resistance and malignant progression via protein deglutathionylation, and GSTO1/NPM1/AKT/NF-κB axis as a potential therapeutic vulnerability in lung adenocarcinoma.


Assuntos
Adenocarcinoma de Pulmão , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB , Glutationa Transferase , Neoplasias Pulmonares , Proteínas Nucleares , Nucleofosmina , Inibidores de Proteínas Quinases , Humanos , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/metabolismo , Receptores ErbB/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Glutationa Transferase/metabolismo , Glutationa Transferase/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Animais , Camundongos , Linhagem Celular Tumoral , Metástase Neoplásica , Transdução de Sinais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , NF-kappa B/metabolismo
3.
J Med Chem ; 67(11): 8730-8756, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38817193

RESUMO

The secretory glutaminyl cyclase (sQC) and Golgi-resident glutaminyl cyclase (gQC) are responsible for N-terminal protein pyroglutamation and associated with various human diseases. Although several sQC/gQC inhibitors have been reported, only one inhibitor, PQ912, is currently undergoing clinic trials for the treatment of Alzheimer's disease. We report an X-ray crystal structure of sQC complexed with PQ912, revealing that the benzimidazole makes "anchor" interactions with the active site zinc ion and catalytic triad. Structure-guided design and optimization led to a series of new benzimidazole derivatives exhibiting nanomolar inhibition for both sQC and gQC. In a MPTP-induced Parkinson's disease (PD) mouse model, BI-43 manifested efficacy in mitigating locomotor deficits through reversing dopaminergic neuronal loss, reducing microglia, and decreasing levels of the sQC/gQC substrates, α-synuclein, and CCL2. This study not only offers structural basis and new leads for drug discovery targeting sQC/gQC but also provides evidence supporting sQC/gQC as potential targets for PD treatment.


Assuntos
Aminoaciltransferases , Benzimidazóis , Inibidores Enzimáticos , Animais , Aminoaciltransferases/antagonistas & inibidores , Aminoaciltransferases/metabolismo , Benzimidazóis/química , Benzimidazóis/farmacologia , Benzimidazóis/síntese química , Cristalografia por Raios X , Camundongos , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/uso terapêutico , Relação Estrutura-Atividade , Modelos Animais de Doenças , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Descoberta de Drogas , Masculino , Modelos Moleculares
4.
J Hazard Mater ; 471: 134415, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38677113

RESUMO

The migration and transformation mechanisms of arsenic (As) in soil environments necessitate an understanding of its influencing processes. Here, we investigate the subsurface biogeochemical transformation of As and iron (Fe) through amended in the top 20 cm with iron oxidizing bacteria (FeOB) and organic fertilizer (OF). Our comprehensive 400-day field study, conducted in a calcareous soil profile sectioned into 20 cm increments, involved analysis by sequential extraction and assessment of microbial properties. The results reveal that the introduction of additional OF increased the release ratio of As/Fe from the non-specific adsorption fraction (136.47 %) at the subsoil depth (40-60 cm), underscoring the importance of sampling at various depths and time points to accurately elucidate the form, instability, and migration of As within the profile. Examination of bacterial interaction networks indicated a disrupted initial niche in the bottom layer, resulting in a novel cooperative symbiosis. While the addition of FeOB did not lead to the dominance of specific bacterial species, it did enhance the relative abundance of As-tolerant Acidobacteria and Gemmatimonadetes in both surface (39.2 % and 38.76 %) and deeper soils (44.29 % and 23.73 %) compared to the control. Consequently, the amendment of FeOB in conjunction with OF facilitated the formation of poorly amorphous Fe (hydr)oxides in the soil, achieved through abiotic and biotic sequestration processes. Throughout the long-term remediation process, the migration coefficient of bioavailable As within the soil profile decreased, indicating that these practices did not exacerbate As mobilization. This study carries significant implications for enhancing biogeochemical cycling in As-contaminated Sierozem soils and exploring potential bioremediation strategies. ENVIRONMENTAL IMPLICATION: The long-term exposure of sewage irrigation has potential adverse effects on the local ecosystem, causing serious environmental problems. Microorganisms play a vital role in the migration and transformation of arsenic in calcareous soil in arid areas, which highlights the necessity of understanding its dynamics. The vertical distribution, microbial community and fate of arsenic in calcareous farmland soil profile in northwest China were studied through field experiments. The results of this work have certain significance for the remediation of arsenic-contaminated soil in arid areas, and provide new insights for the migration, transformation and remediation of arsenic in this kind of soil.


Assuntos
Arsênio , Bactérias , Fertilizantes , Ferro , Oxirredução , Microbiologia do Solo , Poluentes do Solo , Fertilizantes/análise , Arsênio/metabolismo , Ferro/metabolismo , Ferro/química , Bactérias/metabolismo , Poluentes do Solo/metabolismo , Poluentes do Solo/análise , Solo/química , Recuperação e Remediação Ambiental/métodos , Fazendas , Biodegradação Ambiental
5.
Hellenic J Cardiol ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38582140

RESUMO

BACKGROUND: Sacubitril/valsartan (S/V) has been shown to be an effective antihypertensive drug combination. However, its therapeutic effects on blood pressure (BP), hemodynamics, and left ventricular (LV) remodeling in resistant hypertension (RHTN) remain unclear. METHODS: Eighty-six patients completed this self-control study, during which olmesartan was administered within the first 8 weeks (phase 1), followed by S/V within the second 8 weeks (phase 2), with nifedipine and hydrochlorothiazide taken as background medications. Office BP, echocardiography, and hemodynamics assessment using impedance cardiography were performed at baseline and at the eighth and sixteenth weeks. RESULTS: The reduction in office BP was larger in phase 2 than in phase 1 (19.59/11.66 mmHg vs. 2.88/1.15 mmHg). Furthermore, the treatment in phase 2 provided greater reductions in systemic vascular resistance index (SVRI) and thoracic blood saturation ratio (TBR), with differences between the two phases of -226.59 (-1212.80 to 509.55) dyn·s/cm5/m2 and -0.02 (-0.04 to 0.02). Switching from olmesartan to S/V also significantly reduced E/E', LV mass index, LV end-diastolic volume index, and LV end-systolic volume index (all P < 0.05). Decreases in arterial stiffness, SVRI, and TBR were correlated with changes in indicators of LV remodeling (all P < 0.05). This correlation persisted even after adjusting for confounders including changes in BP. CONCLUSIONS: Switching from olmesartan to S/V effectively lowered BP and reversed ventricular remodeling in RHTN. In addition, hemodynamic improvement was also observed. Changes in hemodynamics played an important role in reversing LV remodeling of S/V, and were independent of its antihypertensive effect.

6.
Sci Total Environ ; 920: 170959, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38365035

RESUMO

Immobilization stands as the most widely adopted remediation technology for addressing heavy metal(loid) contamination in soil. However, it is crucial to acknowledge that this process does not eliminate pollutants; instead, it confines them, potentially leaving room for future mobilization. Presently, our comprehension of the temporal variations in the efficacy of immobilization, particularly in the context of its applicability to arid farmland, remains severely limited. To address this knowledge gap, our research delves deep into the roles of iron-oxidizing bacteria (FeOB) and organic fertilizer (OF) in the simultaneous immobilization of arsenic (As) and cadmium (Cd) in soils. We conducted laboratory incubation and field experiments to investigate these phenomena. When OF was combined with FeOB, a noteworthy transformation of available As and Cd into stable species, such as the residual state and combinations with Fe-Mn/Al oxides, was observed. This transformation coincided with changes in soil properties, including pH, Eh, soluble Fe, and dissolved organic carbon (DOC). Furthermore, we observed synergistic effects between available As and Cd when treated with bacteria and OF individually. The stabilization efficiency of As and Cd, as determined by the Toxicity Characteristic Leaching Procedure, reached its highest values at 33.39 % and 24.67 %, respectively, after 120 days. Nevertheless, the formation of iron­calcium complexes was disrupted due to pH fluctuations. Hence, long-term monitoring and model development are essential to enhance our understanding of the remediation process. The application of organic fertilizer and the use of FeOB in calcareous soil hold promise for the restoration of polluted soil and the maintenance of soil health by mitigating the instability of heavy metals(loid).


Assuntos
Arsênio , Metais Pesados , Poluentes do Solo , Cádmio/análise , Arsênio/análise , Solo/química , Fertilizantes , Metais Pesados/análise , Ferro , Bactérias/metabolismo , Oxirredução , Poluentes do Solo/análise
7.
Sci Total Environ ; 913: 169547, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38160821

RESUMO

Anthropogenic activities release significant quantities of trace elements into the atmosphere, which can infiltrate ecosystems through both wet and dry deposition, resulting in ecological harm. Although the current study focuses on the emission inventory and deposition of trace elements, their complex interactions remain insufficiently explored. In this study, we employ emission inventories and deposition data for eight TEs (Cr, Mn, Ni, Cu, Zn, As, Cd, Pb) in Lanzhou City to unveil the relationship between these two aspects. Emissions in Lanzhou can be roughly divided into two periods centered around 2017. Preceding 2017, industrial production constituted the primary source of TEs emissions except for As; coal combustion was the primary contributor to Cr, Mn, and As emissions; waste incineration played a significant role in As, Zn, and Cd emissions; biomass combustion influenced Cr and Cd emissions; and transportation sources were the predominant contributors to Pb and Cu emissions. With the establishment of waste-to-energy plants and the implementation of ultra-low emission retrofits, emissions from these sources decreased substantially after 2017. Consequently, emissions from industrial production emerged as the main source of TEs. The deposition concentrations of Cr, Mn, Ni, Cu, and Pb followed a similar trend to the emissions. However, Cd and As exhibited lower emissions and a less pronounced response relationship. Moreover, Zn concentrations fluctuated within a narrow range and showed a weaker response to emissions. The consistent changes in emissions and TEs deposition concentrations signify a shift in deposition pollution in Lanzhou city from Coal-fired pollution to that driven by transportation and industrial activities. Within this transition, the industrial production process offers significant potential for emission reduction. This insight provides a crucial foundation for managing TEs pollution and implementing strategies to prevent ecological risks.

8.
Environ Monit Assess ; 195(12): 1488, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37975891

RESUMO

This study aimed to investigate the distribution and migration characteristics of lead (Pb) and zinc (Zn) in paddy soils in Hunan Province, China. A total of 343 soil samples from 63 profiles were collected from typical regions. The concentration, spatial distribution, and migration behaviors of Pb and Zn in the paddy soils were examined. The results showed that (1) the concentration ranges of Pb and Zn in the surface layer were 17.62-114.07 mg/kg and 44.98-146.84 mg/kg, respectively. (2) The content was higher in the middle and lower reaches of the Xiangjiang River basin horizontally and exhibited shallow enrichment characteristics vertically. (3) Pb migration was weaker than Zn migration, and the parent material had the most significant influence on Pb and Zn content in the bottom soil layer. The research results will clarify the characteristics of Pb and Zn contents in paddy soils in Hunan Province, further understand the horizontal distribution and vertical migration and transformation characteristics of Pb and Zn contents in paddy soils, and provide basic data for scientific rice cultivation and safe food production.


Assuntos
Metais Pesados , Oryza , Poluentes do Solo , Zinco/análise , Solo , Chumbo , Poluentes do Solo/análise , Monitoramento Ambiental , China , Metais Pesados/análise
9.
J Health Popul Nutr ; 42(1): 81, 2023 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-37587534

RESUMO

BACKGROUND: Hyperhomocysteinemia is one of cardiovascular disease risk factors and fasting homocysteine levels are significantly elevated in male compared to female acute coronary syndrome (ACS) patients with normal renal function. However, it is not known the sex related determinants of plasma homocysteine levels in ACS subjects without renal dysfunction. METHODS: A total of 165 ACS participants with normal plasma creatinine who underwent coronary angiography were included in the present study. Clinical parameters, homocysteine, fasting glucose and lipid profile, hemoglobin, white blood cell, platelets, creatinine, cystatin C, blood urea nitrogen, uric acid (UA), and albumin were measured. Multivariate linear regression analyses were used to recognize the predictive factors for homocysteine. RESULTS: The levels of plasma homocysteine were significantly higher in men than in women (P < 0.0001). In males, homocysteine (log10) was positively associated with hypertension (r = 0.569, P < 0.001), creatinine (r = 0.367, P < 0.001) and cystatin C (log10) (r = 0.333, P = 0.001). In females, homocysteine (log10) was positively correlated with age (r = 0.307, P = 0.107), hypertension (r = 0.456, P < 0.001), creatinine (r = 0.341, P = 0.008), cystatin C (log10) (r = 0.429, P = 0.001) and UA (r = 0.569, P < 0.001) whereas was negatively associated with LDL-C (r = - 0.298, P = 0.021) and ApoB (r = - 0.273, P = 0.033). Parameters up to statistical significance in males or females were incorporated into the stepwise linear regression models. In men, hypertension (P < 0.001) and creatinine (P = 0.031) were independently related to homocysteine. Most of the variability of homocysteine levels in males were only determined by hypertension. In women, cystatin C (log10) (P = 0.004) and hypertension (P = 0.005) were independently related to homocysteine (log10). Plasma cystatin C had a higher explanatory value than hypertension in females. CONCLUSIONS: Hypertension and cystatin C could explain most of the sex differences in serum homocysteine levels in ACS subjects with normal serum creatinine. This finding suggested the importance of making different strategies in males and females to manage hyperhomocysteinemia effectively in ACS subjects without renal dysfunction.


Assuntos
Síndrome Coronariana Aguda , Hiper-Homocisteinemia , Hipertensão , Nefropatias , Feminino , Humanos , Masculino , Creatinina , Cistatina C , Caracteres Sexuais , Hiper-Homocisteinemia/complicações , Hipertensão/complicações
10.
RSC Adv ; 13(31): 21271-21276, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37456539

RESUMO

The morphologies and exposed surfaces of ceria nanocrystals are important factors in determining their performance. In order to establish a structure-property relationship for ceria nanomaterials, it is essential to have materials with well-defined morphologies and specific exposed facets. This is also crucial for acquiring high resolution 17O solid-state NMR spectra. In this study, we explore the synthesis conditions for preparing CeO2 nanorods with exposed (111) facets. The effects of alkali concentration, hydrothermal temperature and time, cerium source and oxidation agent are investigated and optimal synthesis conditions are found. The resulting CeO2 nanorods show very narrow 17O NMR peaks for the oxygen ions in the first, second and third layers, providing a foundation for future research on mechanisms involving ceria materials using 17O solid-state NMR spectroscopy.

11.
Front Pharmacol ; 14: 1038457, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37201027

RESUMO

Introduction: Kidney cancer is one of the most common and lethal urological malignancies. Discovering a biomarker that can predict prognosis and potential drug treatment sensitivity is necessary for managing patients with kidney cancer. SUMOylation is a type of posttranslational modification that could impact many tumor-related pathways through the mediation of SUMOylation substrates. In addition, enzymes that participate in the process of SUMOylation can also influence tumorigenesis and development. Methods: We analyzed the clinical and molecular data which were obtanied from three databases, The Cancer Genome Atlas (TCGA), the National Cancer Institute's Clinical Proteomic Tumor Analysis Consortium (CPTAC), and ArrayExpress. Results: Through analysis of differentially expressed RNA based on the total TCGA-KIRC cohort, it was found that 29 SUMOylation genes were abnormally expressed, of which 17 genes were upregulated and 12 genes were downregulated in kidney cancer tissues. A SUMOylation risk model was built based on the discovery TCGA cohort and then validated successfully in the validation TCGA cohort, total TCGA cohort, CPTAC cohort, and E-TMAB-1980 cohort. Furthermore, the SUMOylation risk score was analyzed as an independent risk factor in all five cohorts, and a nomogram was constructed. Tumor tissues in different SUMOylation risk groups showed different immune statuses and varying sensitivity to the targeted drug treatment. Discussion: In conclusion, we examined the RNA expression status of SUMOylation genes in kidney cancer tissues and developed and validated a prognostic model for predicting kidney cancer outcomes using three databases and five cohorts. Furthermore, the SUMOylation model can serve as a biomarker for selecting appropriate therapeutic drugs for kidney cancer patients based on their RNA expression.

12.
Environ Sci Pollut Res Int ; 30(26): 68258-68270, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37119488

RESUMO

In arid soil with low-iron and high-calcium carbonate contents, the fate of arsenic (As) is mainly controlled by the contents of calcium and organic matter in the soil. However, there is still a lack of knowledge about their interaction and that effect on their absorption by maize. The purpose of this study was to explore the long-term immobilization and repair mechanism of in situ As-contaminated farmland. We designed three treatments: iron-oxidizing bacteria (FeOB), organic fertilizer, FeOB and organic fertilizer added in combination. After 140-day field farmland remediation trial, the results showed that the FeOB can effectively immobilize the water-soluble As (FS1) in soil, and the organic fertilizer promoted the remediation of FeOB. In addition, the content of As in maize grains was reduced after treatment by FeOB and organic fertilizer. The XRD and XPS analysis of the topsoil showed that the combined treatment of FeOB and organic fertilizer promoted the formation of calcium arsenate mineral with low solubility and high stability; As(III) would gradually transform into As(V). The biological iron (hydr)oxide can increase the contents of Fe and As in the rhizosphere and form iron plaques on the surface of the roots by SEM-EDS analysis of maize root. Collectively, these results clarify the main biogeochemical ways to control the fate of As in calcareous soils with low-iron and low-organic matter contents and provide a basis for in situ remediation of As.


Assuntos
Arsênio , Recuperação e Remediação Ambiental , Poluentes do Solo , Arsênio/análise , Fertilizantes/análise , Poluentes do Solo/análise , Ferro/química , Solo/química , Bactérias , Oxirredução
13.
Bioorg Chem ; 135: 106487, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36996510

RESUMO

SIRT5 has been implicated in various physiological processes and human diseases, including cancer. Development of new highly potent, selective SIRT5 inhibitors is still needed to investigate disease-related mechanisms and therapeutic potentials. We here report new ε-N-thioglutaryllysine derivatives, which were designed according to SIRT5-catalysed deacylation reactions. These ε-N-thioglutaryllysine derivatives displayed potent SIRT5 inhibition, of which the potential photo-crosslinking derivative 8 manifested most potent inhibition with an IC50 value of 120 nM to SIRT5, and low inhibition to SIRT1-3 and SIRT6. The enzyme kinetic assays revealed that the ε-N-thioglutaryllysine derivatives inhibit SIRT5 by lysine-substrate competitive manner. Co-crystallographic analyses demonstrated that 8 binds to occupy the lysine-substate binding site by making hydrogen-bonding and electrostatic interactions with SIRT5-specific residues, and is likely positioned to react with NAD+ and form stable thio-intermediates. Compound 8 was observed to have low photo-crosslinking probability to SIRT5, possibly due to inappropriate position of the diazirine group as observed in SIRT5:8 crystal structure. This study provides useful information for developing drug-like inhibitors and cross-linking chemical probes for SIRT5-related studies.


Assuntos
Sirtuínas , Humanos , Sirtuínas/metabolismo , Lisina/química , Sítios de Ligação
14.
Drug Resist Updat ; 68: 100957, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36990047

RESUMO

Resistance to epidermal growth factor receptor (EGFR) inhibitors, from the first-generation erlotinib to the third generation osimertinib, is a clinical challenge in the treatment of patients with EGFR-mutant lung adenocarcinoma. Our previous work found that a novel allosteric inhibitor of phosphoglycerate mutase 1 (PGAM1), HKB99, restrains erlotinib resistance in lung adenocarcinoma cells. However, the role of HKB99 in osimertinib resistance and its underlying molecular mechanism remains to be elucidated. Herein, we found that IL-6/JAK2/STAT3 signaling pathway is aberrantly activated in both erlotinib and osimertinib resistant cells. Importantly, HKB99 significantly blocks the interaction of PGAM1 with JAK2 and STAT3 via the allosteric sites of PGAM1, which leads to inactivation of JAK2/STAT3 and thereby disrupts IL-6/JAK2/STAT3 signaling pathway. Consequently, HKB99 remarkably restores EGFR inhibitor sensitivity and exerts synergistic tumoricidal effect. Additionally, HKB99 alone or in combination with osimertinib down-regulated the level of p-STAT3 in xenograft tumor models. Collectively, this study identifies PGAM1 as a key regulator in IL-6/JAK2/STAT3 axis in the development of resistance to EGFR inhibitors, which could serve as a therapeutic target in lung adenocarcinoma with acquired resistance to EGFR inhibitors.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Cloridrato de Erlotinib/farmacologia , Cloridrato de Erlotinib/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Interleucina-6/genética , Interleucina-6/farmacologia , Interleucina-6/uso terapêutico , Fosfoglicerato Mutase/metabolismo , Fosfoglicerato Mutase/farmacologia , Resistencia a Medicamentos Antineoplásicos , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Receptores ErbB , Transdução de Sinais , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Mutação , Linhagem Celular Tumoral , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Janus Quinase 2/farmacologia
15.
Sci Total Environ ; 870: 162012, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-36737027

RESUMO

The contrasting chemical behaviors of two toxic elements, arsenic (As) and cadmium (Cd) in co-contamination calcareous soil and its absorption by crops have not been thoroughly explored, especially in the implementation of the measure of prohibiting the use of wastewater to irrigate farmland. We propose that the present environmental characteristics of ecologically fragile areas and appropriate restoration measures are critical determinant of soil remediation. In this study, the typical field farmland irrigated by industrial and domestic wastewater in the Chinese Loess Plateau for >50 years was selected. The results showed that after the sewage irrigation was stopped, the mean contents of Cd (7.09 mg/kg) and As (13.47 mg/kg) in the soil were still rising, which might be a potential input source. The average values of soil risk indices such as the potential ecological risk (PERI = 2394), pollution load index (PLI > 4 for 60 % of studied samples), and degree of contamination (Dc = 86.6) showed severe soil pollution in the study area. The decrease of soil pH, the loss of soil texture and calcium carbonate were found to be the reasons for the high chemical activity of Cd. The bioconcentration factors (< 0.2) and translocation factor (> 1.0) of Cd indicate that corn is an excluder plant and an ideal phytoremediation method. Thus, 20 % of studied samples were higher than maximum permitted levels of Cd in grain, indicating potential related health hazards. On the contrary, As was mainly adsorbed in calcareous soil, and its bioavailability was lower compared with Cd. The difference between DTPA extraction and sequential extraction may be due to the transformation of chemical forms, resulting in unstable fractions increased the bioavailability of toxic elements. Overall, the findings provide new insights for solutions to manage and repair farmlands under the post-wastewater irrigation period.


Assuntos
Arsênio , Metais Pesados , Poluentes do Solo , Cádmio/análise , Solo/química , Zea mays , Águas Residuárias , Poluentes do Solo/análise , Produtos Agrícolas , China , Biodegradação Ambiental , Metais Pesados/análise , Monitoramento Ambiental
16.
Nanomaterials (Basel) ; 13(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36677988

RESUMO

The molecular dynamics method was used to analyze the influence of simulated temperature on the damage expansion process of the 3C-SiC sample under nano-indentation loading in order to study the influence of temperature on the internal damage and expansion mechanism of the 3C-SiC single crystal sample further during the nano-indentation loading process. A simulation test platform for diamond indenter indentation was established. The process of stress and strain distribution, dislocation evolution, dislocation expansion and potential energy change were analyzed, combined with the radial distribution function and load displacement curve. The influence of temperature on the 3C-SiC material was discussed. The variation trend of the potential energy-step curve is basically the same at the temperatures of 0 K, 300 K, 600 K and 900 K. The difference in strain distribution was characterized by the influence of temperature on stress intensity, expansion direction and type. The microcosmic manifestation is the significant difference in the dislocation slip at low temperature. In the process of dislocation evolution and expansion, dislocation climbs at room temperature and increases at high temperature, which is closely related to energy release. This study has certain guiding significance for investigating the internal damage difference and temperature effect of the 3C-SiC sample.

17.
Front Cardiovasc Med ; 9: 997109, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36523357

RESUMO

Purpose: Enhanced external counterpulsation (EECP) is a new non-drug treatment for coronary artery disease (CAD). However, the long-term effect of EECP on endothelial dysfunction and exercise tolerance, and the relationship between the changes in the endothelial dysfunction and exercise tolerance in the patients with coronary heart disease are still unclear. Methods: A total of 240 patients with CAD were randomly divided into EECP group (n = 120) and control group (n = 120). All patients received routine treatment of CAD as the basic therapy. Patients in the EECP group received 35 1-h daily sessions of EECP during 7 consecutive weeks while the control group received the same treatment course, but the cuff inflation pressure was 0-10 mmHg. Peak systolic velocity (PSV), end diastolic velocity (EDV), resistance index (RI), and inner diameter (ID) of the right carotid artery were examined using a Color Doppler Ultrasound and used to calculate the fluid shear stress (FSS). Serum levels of human vascular endothelial cell growth factor (VEGF), vascular endothelial cell growth factor receptor 2 (VEGFR2), and human angiotensin 2 (Ang2) were determined by enzyme-linked immunosorbent assay (ELISA). Exercise load time, maximal oxygen uptake (VO2max ), metabolic equivalent (METs), anaerobic threshold (AT), peak oxygen pulse (VO2max/HR) were assessed using cardiopulmonary exercise tests. Results: After 1 year follow-up, the EDV, PSV, ID, and FSS were significantly increased in the EECP group (P < 0.05 and 0.01, respectively), whereas there were no significant changes in these parameters in the control group. The serum levels of VEGF and VEGFR2 were elevated in the EECP and control groups (all P < 0.05). However, the changes in VEGF and VEGFR2 were significantly higher in the EECP group than in the control group (P < 0.01). The serum level of Ang2 was decreased in the EECP group (P < 0.05) and no obvious changes in the control group. As for exercise tolerance of patients, there were significant increases in the exercise load time, VO2max, VO2max/HR, AT and METs in the EECP group (all P < 0.05) and VO2max and METs in the control group (all P < 0.05). Correlation analyses showed a significant and positive correlations of VEGF and VEGFR2 levels with the changes in FSS (all P < 0.001). The correlations were still remained even after adjustment for confounders (all Padjustment < 0.001). Linear regression displays the age, the medication of ACEI (angiotensin-converting enzyme inhibitors) or ARB (angiotensin receptor blockers), the diabetes and the changes in VEGF and VEGFR2 were positively and independently associated with the changes in METs after adjustment for confounders (all Padjustment < 0.05). Conclusion: The data of our study suggested that EECP is a useful therapeutic measurement for amelioration of endothelial dysfunction and long-term elevation of exercise tolerance for patients with coronary heart disease. Clinical trial registration: [http://www.chictr.org.cn/], identifier [ChiCTR1800020102].

18.
J Am Chem Soc ; 144(51): 23340-23351, 2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-36512749

RESUMO

ZnO plays a very important role in many catalytic processes involving H2, yet the details on their interactions and H2 activation mechanism are still missing, owing to the lack of a characterization method that provides resolution at the atomic scale and follows the fate of oxide surface species. Here, we apply 17O solid-state NMR spectroscopy in combination with DFT calculations to unravel the surface structure of ZnO nanorods and explore the H2 activation process. We show that six different types of oxygen ions in the surface and subsurface of ZnO can be distinguished. H2 undergoes heterolytic dissociation on three-coordinated surface zinc and oxygen ions, while the formed hydride species migrate to nearby oxygen species, generating a second hydroxyl site. When oxygen vacancies are present, homolytic dissociation of H2 occurs and zinc hydride species form from the vacancies. Reaction mechanisms on oxide surfaces can be explored in a similar manner.


Assuntos
Óxido de Zinco , Catálise , Óxidos , Oxigênio , Zinco
19.
Ecotoxicol Environ Saf ; 245: 114126, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36183429

RESUMO

The bio-remediation of As-polluted farmlands in the arid area is seldomly reported. This study aimed at understanding the impact of DOM, Fe-oxides, and FeOB biogeochemical processes on As remediation. The approaches used included: FeOB strain Pseudomonas flavescens LZU-3; Batch-experiment. Our results showed that all FeOB tested effectively immobilized As (>95%) during microbial mineralization; DOM play an important role in the reduction of Fe(III)(hydr)oxides and As(V); Less-crystallized ferrihydrite transform to more-crystallized goethite and secondary minerals; Under the reaction of FeOB and DOM, the As-Fe-OM ternary compound were formed, containing N, S, C and O functional group; The addition of OM can clearly reduce soil Eh, promoting dissolution of As in bound to iron oxides, co-precipitation of the amorphous iron oxide in Fe(III)-OM-FeOB, closely related to As in bound to insoluble organics and sulfides and mineral residues, which plays an important role in controlling the mobilization of As. This study provides controlling of As transportation and transformation in the As-DOM-Bio-Fe ternary system as As-remediation technology in the arid soil.


Assuntos
Compostos Férricos , Ferro , Bactérias/metabolismo , Compostos Férricos/química , Ferro/química , Minerais/química , Oxirredução , Óxidos/metabolismo , Solo/química , Sulfetos/metabolismo
20.
Front Immunol ; 13: 975057, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36189312

RESUMO

Kidney cancer is one of the most common urological cancers worldwide, and kidney renal clear cell cancer (KIRC) is the major histologic subtype. Our previous study found that von-Hippel Lindau (VHL) gene mutation, the dominant reason for sporadic KIRC and hereditary kidney cancer-VHL syndrome, could affect VHL disease-related cancers development by inducing telomere shortening. However, the prognosis role of telomere-related genes in kidney cancer has not been well discussed. In this study, we obtained the telomere-related genes (TRGs) from TelNet. We obtained the clinical information and TRGs expression status of kidney cancer patients in The Cancer Genome Atlas (TCGA) database, The International Cancer Genome Consortium (ICGC) database, and the Clinical Proteomic Tumor Analysis Consortium (CPTAC) database. Totally 353 TRGs were differential between tumor and normal tissues in the TCGA-KIRC dataset. The total TCGA cohort was divided into discovery and validation TCGA cohorts and then using univariate cox regression, lasso regression, and multivariate cox regression method to conduct data analysis sequentially, ten TRGs (ISG15, RFC2, TRIM15, NEK6, PRKCQ, ATP1A1, ELOVL3, TUBB2B, PLCL1, NR1H3) risk model had been constructed finally. The kidney patients in the high TRGs risk group represented a worse outcome in the discovery TCGA cohort (p<0.001), and the result was validated by these four cohorts (validation TCGA cohort, total TCGA cohort, ICGC cohort, and CPTAC cohort). In addition, the TRGs risk score is an independent risk factor for kidney cancer in all these five cohorts. And the high TRGs risk group correlated with worse immune subtypes and higher tumor mutation burden in cancer tissues. In addition, the high TRGs risk group might benefit from receiving immune checkpoint inhibitors and targeted therapy agents. Moreover, the proteins NEK6, RF2, and ISG15 were upregulated in tumors both at the RNA and protein levels, while PLCL1 and PRKCQ were downregulated. The other five genes may display the contrary expression status at the RNA and protein levels. In conclusion, we have constructed a telomere-related genes risk model for predicting the outcomes of kidney cancer patients, and the model may be helpful in selecting treatment agents for kidney cancer patients.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Humanos , Inibidores de Checkpoint Imunológico , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Neoplasias Renais/patologia , Quinases Relacionadas a NIMA/genética , Prognóstico , Proteína Quinase C-theta/genética , Proteômica , RNA , Fatores de Risco , Telômero/genética
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