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1.
ACS Omega ; 9(15): 17491-17505, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38645376

RESUMEN

Geological bodies are important sources of greenhouse gas (GHG) emissions. Organic-rich oil shale in sedimentary basins is a good gas source rock, the GHG in which will be released into the atmosphere during crushing to affect climate change. Quantitative calculations of GHG emissions during oil shale crushing were carried out on oil shales from the Yaojie (YJ) and Fushun (FS) mining areas in China. Organic geochemistry, X-ray diffraction, and pore structure analysis experiments, as well as the relationship between storage time and GHG emissions, were analyzed to investigate the main controlling factors of GHG release in different types of oil shales. The results showed that the CH4 and CO2 released from the YJ oil shale were 0.002-0.145 mL/g and 0.011-0.054 mL/g, respectively; the CH4 and CO2 released from the FS oil shale were 0.0001-0.0008 mL/g and 0.002-0.045 mL/g, respectively. Residual CH4 release was closely related to total organic carbon (TOC) and maturity: the CH4 released from the organic-rich and mature YJ oil shale was much higher than that of the FS oil shale, which is relatively organic-lean and immature. The control factors of the released CO2 vary in different regions: CO2 released from the YJ oil shale was somewhat affected by the TOC, while that released from the FS oil shale was mainly controlled by carbonate minerals and their contributing pores. The results of pore structure and organic maceral analyses indicated that both organic and inorganic pores of the YJ oil shale are occupied by asphaltenes, forming a key gas preservation mechanism of residual CH4 and CO2 as solutes dissolved in asphaltenes. In addition, CO2 has a greater absorptive capacity than CH4 and is therefore more difficult to release during the same crushing time. As oil shale is stored for longer periods, residual CH4 will be preferentially released to the atmosphere, while residual CO2 will be released in large quantities during crushing.

2.
Bioorg Chem ; 147: 107370, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38621338

RESUMEN

Here, we introduce a novel and effective approach utilizing a cathepsin B cleavage albumin-binding SN38 prodrug specifically designed for the treatment of metastatic breast cancer. Termed Mal-va-mac-SN38, our prodrug exhibits a unique ability to rapidly and covalently bind with endogenous albumin, resulting in the formation of HSA-va-mac-SN38. This prodrug demonstrates exceptional stability in human plasma. Importantly, HSA-va-mac-SN38 showcases an impressive enhancement in cellular uptake by 4T1 breast cancer cells, primarily facilitated through caveolin-mediated endocytosis. Intriguingly, the release of the active SN38, is triggered by the enzymatic activity of cathepsin B within the lysosomal environment. In vivo studies employing a lung metastasis 4T1 breast cancer model underscore the potency of HSA-va-mac-SN38. Histological immunohistochemical analyses further illuminate the multifaceted impact of our prodrug, showcasing elevated levels of apoptosis, downregulated expression of matrix metalloproteinases, and inhibition of angiogenesis, all critical factors contributing to the anti-metastatic effect observed. Biodistribution studies elucidate the capacity of Mal-va-mac-SN38 to augment tumor accumulation through covalent binding to serum albumin, presenting a potential avenue for targeted therapeutic interventions. Collectively, our findings propose a promising therapeutic avenue for metastatic breast cancer, through the utilization of a cathepsin B-cleavable albumin-binding prodrug.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Catepsina B , Diseño de Fármacos , Profármacos , Profármacos/síntesis química , Profármacos/química , Profármacos/farmacología , Catepsina B/metabolismo , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Animales , Ratones , Estructura Molecular , Relación Estructura-Actividad , Ensayos de Selección de Medicamentos Antitumorales , Proliferación Celular/efectos de los fármacos , Ratones Endogámicos BALB C , Relación Dosis-Respuesta a Droga , Apoptosis/efectos de los fármacos
3.
Chemosphere ; 310: 136770, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36228724

RESUMEN

Huge volumes of wastewater containing organic flotation reagents such as xanthates have been released into the environment via mining activities, greatly threatening the eco-environment safety. A simple and fast method is urgently needed for accurate analysis of various xanthates in mining and environmental water. Here, a robust method is realized for simultaneous determination of three trace xanthates (i.e., potassium ethyl xanthate, potassium butyl xanthate, and potassium isopropyl xanthate) in environmental water samples, including eutrophic water and flotation wastewater using solid phase extraction (SPE) and HPLC-MS/MS. HPLC-MS/MS parameters, SPE cartridges and eluting solvents, pH values, and SPE procedures were optimized. The new method had an excellent linearity in the range of 1-1000 µg/L (R2 ≥ 0.998), low limits of detection (0.02-0.68 µg/L), and satisfactory accuracy and precision (72.9%-107.6% of average recoveries and <5% of relative standard deviations at 1, 10, 50, and 500 µg/L of xanthates). This is a first method developed for determination of trace xanthates in water samples. It was successfully applied to determine the target analytes in outdated flotation wastewater and river water samples, warranting the occurrence of trace xanthates (0.13-16.9 µg/L) in water and necessity of systematic investigation on environmental fate and risk of xanthates.


Asunto(s)
Insecticidas , Contaminantes Químicos del Agua , Espectrometría de Masas en Tándem/métodos , Aguas Residuales/química , Agua/química , Contaminantes Químicos del Agua/análisis , Extracción en Fase Sólida/métodos , Cromatografía Liquida/métodos , Cromatografía Líquida de Alta Presión/métodos , Insecticidas/análisis , Potasio
4.
Ann Transl Med ; 10(21): 1175, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36467354

RESUMEN

Background: Endometriosis is a chronic condition that affects women of child-bearing age. Since the etiology and pathogenesis of endometriosis have not been fully elucidated, it is important to investigate the mechanisms that lead to the deterioration of endometriosis. Methods: In this study, the transcriptome data of patients with normal, mild, and severe endometriosis were examined using the GSE51981 dataset obtained from the Gene Expression Omnibus database. Short Time Series Expression Miner (STEM) was used to screen the genes with continuous expression disorder in the development process, and the core genes were identified by constructing a protein-protein interaction network. The molecular mechanisms of endometriosis were examined using enrichment analysis. Finally, the transcription factors that regulate the core genes were predicted and the comprehensive mechanisms involved in the development of endometriosis were examined. Results: A total of 3,472 differentially expressed genes were identified from the normal, mild, and severe endometriosis samples. These were allocated into 12 modules and HRAS, HSP90AA1, TGFB1, TP53, and UBC were selected as the core genes. Enrichment analysis showed that the genes in modules 6, 7, and 9 were significantly related to oxygen levels, metallic processes, and hormone levels, respectively. Transcription factor prediction analysis showed that TP53 regulates HRAS to participate in immune related signaling pathways. Drug prediction analysis identified 792 drugs that interact with the targeted core genes. Conclusions: This study explored the molecular mechanisms involved in the development of endometriosis and identified potential biomarkers of endometriosis. This data may provide novel targets and research directions for the diagnosis and treatment of endometriosis.

5.
J Agric Food Chem ; 70(46): 14622-14632, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36375011

RESUMEN

Perfluoroalkyl acids (PFAAs) are emerging ionic organic pollutants worldwide. Great amounts of extracellular DNA (∼mg/kg) coexist with PFAAs in the environment. However, PFAA-DNA interactions and effects of such interactions have not been well studied. Herein, we used isothermal titration calorimetry (ITC), spectroscopy, and computational simulations to investigate the PFAA-DNA interactions. ITC assays showed that specific binding affinities of PFHxA-DNA, PFOA-DNA, PFNA-DNA, and PFOS-DNA were 5.14 × 105, 3.29 × 105, 1.99 × 105, and 2.18 × 104 L/mol, respectively, which were about 1-2 orders of magnitude stronger than those of PFAAs with human serum albumin. Spectral analysis suggested interactions of PFAAs with adenine (A), cytosine (C), guanine (G), and thymine (T), among which grooves associated with thymine were the major binding sites. Molecular dynamics simulations and quantum chemical calculations suggested that hydrogen bonds and van der Waals forces were the main interaction forces. Such a PFAA-DNA binding decreased the bioavailability of PFAAs in plant seedlings. The findings will help to improve the current understanding of the interaction between PFAAs and biomacromolecules, as well as how such interactions affect the bioavailability of PFAAs.


Asunto(s)
Brassica , Fluorocarburos , Humanos , Fluorocarburos/análisis , Disponibilidad Biológica , Brassica/genética , Brassica/metabolismo , Timina , ADN/metabolismo
6.
Molecules ; 26(23)2021 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-34885822

RESUMEN

Histone deacetylases (HDACs) play important roles in cell growth, cell differentiation, cell apoptosis, and many other cellular processes. The inhibition of different classes of HDACs has been shown to be closely related to the therapy of cancers and other diseases. In this study, a series of novel CRBN-recruiting HDAC PROTACs were designed and synthesized by linking hydroxamic acid and benzamide with lenalidomide, pomalidomide, and CC-220 through linkers of different lengths and types. One of these PROTACs, denoted 21a, with a new benzyl alcohol linker, exhibited comparably excellent HDAC inhibition activity on different HDAC classes, acceptable degradative activity, and even better in vitro anti-proliferative activities on the MM.1S cell line compared with SAHA. Moreover, we report for the first time the benzyl alcohol linker, which could also offer the potential to be used to develop more types of potent PROTACs for targeting more proteins of interest (POI).


Asunto(s)
Diseño de Fármacos , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Línea Celular , Proliferación Celular/efectos de los fármacos , Inhibidores de Histona Desacetilasas/química , Humanos , Ligandos , Proteolisis/efectos de los fármacos
7.
Int J Oncol ; 51(6): 1920-1928, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29075785

RESUMEN

Lymph node metastasis is one of the most valuable determinants for the prognosis of ovarian cancer. However, the molecular mechanisms underlying lymphangiogenesis in ovarian cancer is still poorly understood. Secreted protein acidic and rich in cysteine (SPARC), a Ca2+-binding matricellular glycoprotein that modulates cell adhesion, migration and differentiation, is thought to play a decisive role in tumor metastasis. Vascular endothelial growth factor (VEGF)-C and VEGF-D contributes to tumor-associated lymphatic vessel growth, enhancing the metastatic spread of tumor cells to lymph nodes. The aim of the present study was to investigate the relationship among SPARC, VEGFs and lymph node metastasis in ovarian cancer. We found that SKOV3 cells expressed high-level SPARC, much more than SKOV3-PM4 cells (a subline with high directional lymphatic metastatic potentials established from the metastatic lymph node generated by human ovarian carcinoma cell line SKOV3 in nude mice) did at both mRNA and protein levels. A SPARC-overexpressed SKOV3-PM4 cell line was constructed and it was found that upregulation of SPARC expression suppressed the growth, migration and invasion of SKOV3-PM4 cells as well as markedly reduced the expression of VEGF-D at both mRNA and protein level by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assay. In 47 of ovarian malignant tissues, the expression of SPARC, VEGF-C and VEGF-D were determined by immunohistochemistry. Lymphatic microvessel density (LVD) and microvessel density (MVD) were evaluated by immunostaining with CD34 and D2-40 antibodies, respectively. We found that SPARC expression was significantly lower in tissues with lymph node metastasis as compared to tissues without lymph node metastasis. SPARC expression was inversely associated with the degree of malignancy and it had a negative correlation with VEGF-C expression, VEGF-D expression, LVD and MVD which were actually higher for advanced tumors than for non-advanced tumors. These results suggest SPARC might function as a tumor suppressor inhibiting angiogenesis and lymphangiogenesis in ovarian cancer by reducing the expression of VEGF-C and VEGF-D.


Asunto(s)
Osteonectina/metabolismo , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Factor C de Crecimiento Endotelial Vascular/biosíntesis , Factor D de Crecimiento Endotelial Vascular/biosíntesis , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Femenino , Humanos , Metástasis Linfática , Microscopía Confocal , Neovascularización Patológica/patología , Osteonectina/genética , Neoplasias Ováricas/irrigación sanguínea , Transfección , Factor C de Crecimiento Endotelial Vascular/genética , Factor D de Crecimiento Endotelial Vascular/genética
8.
Zhonghua Fu Chan Ke Za Zhi ; 49(7): 510-6, 2014 Jul.
Artículo en Chino | MEDLINE | ID: mdl-25327733

RESUMEN

OBJECTIVE: To establish the condition cultrue cell system and co- culture cell system with SKOV3/PM4, HUVEC and to study the changes of their biological characteristics. METHODS: The cells of SKOV3/PM4 and HUVEC were labeled with green and red fluorescent respectively. The cell supernatant of SKOV3/PM4 and HUVEC were collected respectively as the condition medium (e.g: the cell supernatant of HUVEC cells was used as SKOV3/PM4 condition medium)and to establish the condition cultrue cell system and the co- culture cell system of the two cell lines. In the condition cultrue cell system, The morphological changes of cells were observed by HE staining to calculate the mitotic index. The ultrastructural changes of the two cells were observed by transmission electron microscopy (TEM). The growth curve of the cells was determined by methyl thiazolyl tetrazolium (MTT) assay and flow cytometry was used to analyzed the cell cycles. In the co-culture cell system, the interaction of the two cells were detected by laser scanning confocal microscope (LSCM). The expression of matrix metalloproteinase- 2 (MMP- 2) and matrix metalloproteinase- 9 (MMP- 9) were detected by gelatin zymography. RESULTS: Compared with the single culture SKOV3/PM4, the cells which cultured in HUVEC condition medium showed the increase of pseudopodia and nuclear division, the mitotic index respectively were [(4.8 ± 0.8)%, (11.2 ± 0.3)%; P < 0.05]. The growth rate was significantly increased. In cell cycles, it showed the declined cell ratio of G0/G1 phase, respectively [(69.4 ± 3.6)%, (48.4 ± 4.6)%; P < 0.05] and the raised cell ratio of G2/M phase, respectively [(5.2 ± 1.6)%, (24.9 ± 2.2)%; P < 0.05]. Compared with the single culture HUVEC, the cells which cultured in SKOV3/PM4 condition medium showed the significant morphological change and vacuolization in the cytoplasm, Nuclear division was increased and the mitotic index respectively were [(2.7 ± 0.5)%, (5.7 ± 0.6)%; P < 0.05]. The growth rate was slightly declined. In cell cycles, it showed the raised cell ratio in G0/G1 phase, respectively [(51.4 ± 2.2)%, (79.0 ± 4.1)%; P < 0.05] and the declined cell ratio in G2/M phase, respectively [(19.1 ± 1.2)%, (3.3 ± 0.5)%; P < 0.05]. After co-culture for 48 hours, spontaneous fusion between SKOV3/PM4 and HUVEC cell was observed by the laser confocal microscope. Gelatin zymography assay showed that MMP-2 was not expressed in HUVEC cells, low-expressed in SKOV3/PM4 cells and high-expressed in the co-culture SKOV3/PM4+HUVEC cells. The expression of MMP-2 in co-culture SKOV3/PM4+HUVEC cells and SKOV3/PM4 cells respectively were 1 885 ± 84 and 1 209 ± 114 (P < 0.05). But there were no MMP-9 expression in HUVEC cells, SKOV3/PM4 cells, and the co- culture SKOV3/PM4+HUVEC. CONCLUSION: The characteristics of SKOV3/PM4 and HUVEC show significant changes after condition culture and co-culture, it may involve in the microenvironment of the cells and the intercellular crosstalk pathway.


Asunto(s)
Metástasis Linfática , Neoplasias Glandulares y Epiteliales/patología , Neoplasias Ováricas/patología , Carcinoma Epitelial de Ovario , Línea Celular Tumoral , Proliferación Celular , Técnicas de Cocultivo , Medios de Cultivo Condicionados , Citoplasma , Femenino , Citometría de Flujo , Proteínas Fluorescentes Verdes/genética , Células Endoteliales de la Vena Umbilical Humana , Humanos , Ganglios Linfáticos/patología , Metaloproteinasa 2 de la Matriz , Metaloproteinasa 9 de la Matriz , Trasplante de Neoplasias , Neoplasias Glandulares y Epiteliales/genética , Neoplasias Glandulares y Epiteliales/metabolismo , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo
9.
Cancer Biol Med ; 10(4): 221-6, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24349832

RESUMEN

OBJECTIVE: To study explores the effect of HLEC on the secreted proteins of epithelial ovarian cancer (EOC) cells (SKOV3-PM4) with directional highly lymphatic metastasis. METHODS: Supernatants of four groups of cultured cells, namely, SKOV3 (A), SKOV3+HLEC (B), SKOV3-PM4 (C), SKOV3-PM4+HLEC (D), were collected, and their proteins were detected by antibody arrays and iTRAQ-2D-LC-MALDI-TOF/TOF/MS. Significantly differential proteins were further analyzed via bioinformatics and validated in human serums and cell media via ELISA. RESULTS: Results of antibody arrays and mass spectrometry demonstrated that GRN and VEGFA were upregulated in group C (compared with group A), whereas IGFBP7 and SPARC were downregulated in group D (compared with group C). Comprehensive bioinformatics analysis results showed that IGFBP7 and VEGFA were closely linked to each other. Further validation with serums showed statistical significance in VEGFA and IGFBP7 levels among groups of patients with ovarian cancers, benign tumors, and control groups. Two proteins were upegulated in the first group. VEGFA in the control group was downregulated. For IGFBP, upregulation in the control group and down-regulation in the first group were also observed. CONCLUSION: The HLEC microenvironment is closely associated with directional metastasis to lymph nodes and with differential proteins including cell stromal proteins and adhesion factors. The upregulation of VEGFA and GRN and the downregulation of SPARC and IGFBP7 are closely associated with directional metastasis to lymph nodes in EOC cells.

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