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1.
Pharmacol Res ; 203: 107159, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38554790

RESUMEN

Encapsulated cell technology (ECT) is a targeted delivery method that uses the genetically engineered cells in semipermeable polymer capsules to deliver cytokines. Thus far, ECT has been extensively utilized in pharmacologic research, and shows enormous potentials in the treatment of posterior segment diseases. Due to the biological barriers within the eyeball, it is difficult to attain effective therapeutic concentration in the posterior segment through topical administration of drug molecules. Encouragingly, therapeutic cytokines provided by ECT can cross these biological barriers and achieve sustained release at the desired location. The encapsulation system uses permeable materials that allow growth factors and cytokines to diffuse efficiently into retinal tissue. Moreover, the ECT based treatment can be terminated timely when we need to retrieve the implant, which makes the therapy reversible and provides a safer alternative for intraocular gene therapy. Meanwhile, we also place special emphasis on optimizing encapsulation materials and enhancing preservation techniques to achieve the stable release of growth factors and cytokines in the eyeball. This technology holds great promise for the treatment of patients with dry AMD, RP, glaucoma and MacTel. These findings would enrich our understandings of ECT and promote its future applications in treatment of degenerative retinopathy. This review comprises articles evaluating the exactness of artificial intelligence-based formulas published from 2000 to March 2024. The papers were identified by a literature search of various databases (PubMed/MEDLINE, Google Scholar, Cochrane Library and Web of Science).


Asunto(s)
Citocinas , Oftalmopatías , Humanos , Citocinas/metabolismo , Animales , Oftalmopatías/terapia , Oftalmopatías/tratamiento farmacológico , Sistemas de Liberación de Medicamentos/métodos , Encapsulación Celular/métodos
2.
Inorg Chem ; 63(15): 6845-6853, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38568878

RESUMEN

Bis(2,4,4-trimethylpentyl)dithiophosphinic acid, commonly referred to as HBTMPDTP or Cyanex301, is a sulfur-donating ligand that shows considerable promise in the challenging task of separating trivalent actinides (An3+) from lanthanides (Ln3+). Although its effectiveness has been established, the specific molecular details about the preference of HBTMPDTP for americium over europium have remained a mystery, puzzling researchers for over two decades. This study presents a comprehensive, dual-driven separation mechanism for this complex system combining experimental and theoretical approaches. A critical finding is the increased covalency in An-S bonds compared to Ln-S bonds, which plays a significant role in HBTMPDTP's intrinsic selectivity for An3+ over Ln3+. This leads to the formation of distinct An3+ and Ln3+ species, enhancing the ligand's actinide selectivity. Additionally, it provides crucial insights into the coordination chemistry of f-elements with sulfur-donating ligands, thereby deepening our understanding of this intricate field.

3.
Mol Cancer ; 22(1): 148, 2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37679744

RESUMEN

Neutrophils, the most prevalent innate immune cells in humans, have garnered significant attention in recent years due to their involvement in cancer progression. This comprehensive review aimed to elucidate the important roles and underlying mechanisms of neutrophils in cancer from the perspective of their whole life cycle, tracking them from development in the bone marrow to circulation and finally to the tumor microenvironment (TME). Based on an understanding of their heterogeneity, we described the relationship between abnormal neutrophils and clinical manifestations in cancer. Specifically, we explored the function, origin, and polarization of neutrophils within the TME. Furthermore, we also undertook an extensive analysis of the intricate relationship between neutrophils and clinical management, including neutrophil-based clinical treatment strategies. In conclusion, we firmly assert that directing future research endeavors towards comprehending the remarkable heterogeneity exhibited by neutrophils is of paramount importance.


Asunto(s)
Neoplasias , Neutrófilos , Humanos , Neoplasias/genética , Microambiente Tumoral
4.
Inorg Chem ; 62(38): 15565-15574, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37700628

RESUMEN

Complexes of Ni(II) with a series of aryl or alkyl substituent dithiophosphinic acids were characterized by crystallographic structure, sulfur K-edge X-ray absorption spectroscopy (XAS), and density functional theory (DFT). In these complexes, Ni(II) coordinates with four sulfur atoms from two dithiophosphinate anions form a well-defined square-planar structure. Despite the minor differences in the geometry parameters among the complexes, the electronic structure is affected significantly by the substituent group attached to dithiophosphinic acid. In particular, the addition of ortho-CF3 group to the aryl ring constrains the orientation of the aryl ring and enhances the conjugation between the aryl ring and the coordinating core. Sulfur K-edge XAS spectra help further reveal the electronic structure of the complexes. Both the pre-edge feature and rising-edge feature provide abundant information on the molecular orbitals and show a distinctive effect of the substituent groups on the electronic structure of the complexes, which is supposedly relevant to the ligand's performance in Ln(III)/An(III) separation.

5.
Ann Surg Oncol ; 29(4): 2720-2731, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34792696

RESUMEN

BACKGROUND: Prognosis in pancreatic ductal adenocarcinoma (PDAC) remains poor despite improved systemic therapies and surgical techniques. The identification of biomarkers to advance insight in tumor biology and achieve better individualized prognostication could help improve outcomes. Our aim was to elucidate the prognostic role of the four main driver mutations (KRAS, TP53, SMAD4, CDKN2A) and their combinations in resected PDAC. PATIENTS AND METHODS: A retrospective analysis was conducted utilizing the cBioPortal database and National Cancer Institute's Cancer Genomic Atlas (TCGA) on patients in whom next-generation sequencing was performed on upfront resected PDAC from 2012 to 2020. Multivariable Cox regression was implemented to elucidate risk-adjusted predictors of overall (OS) and recurrence-free survival (RFS). Results were validated employing a Johns Hopkins Hospital (JHH) cohort.' RESULTS: In the discovery cohort (n = 587), increased number of mutated driver genes was associated with worse OS (p = 0.047). Specifically, patients with mutations in ≥ 2 driver genes had worse OS than ≤ 1 mutated gene (18.2 versus 32.3 months, p = 0.033). Co-occurrence of mutant (mt)KRAS p.G12D with mtTP53 (median OS, 25.9 months) conferred better prognosis than co-occurrence of other mtKRAS variants (p.G12V/R/other) with mtTP53 (median OS, 16.9 months, p = 0.038). The findings were validated using a JHH cohort. Multivariable risk-adjustment found co-occurrence of mtKRAS p.G12D with mtTP53 to be an independent predictor of beneficial OS and RFS [HR (95% CI): 0.18 (0.03-0.81) and 0.31 (0.11-0.89) respectively]. CONCLUSION: In chemo-naïve resected PDAC, combinations of mutations in the four driver genes are associated with prognosis. In patients with combined mtKRAS and mtTP53, KRAS p.G12D variant confers a better OS and RFS.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Biomarcadores de Tumor/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/cirugía , Humanos , Mutación , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Pronóstico , Proteínas Proto-Oncogénicas p21(ras)/genética , Estudios Retrospectivos , Proteína p53 Supresora de Tumor/genética
6.
Inorg Chem ; 61(16): 6063-6072, 2022 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-35420792

RESUMEN

Comparatively revealing the complexation behavior of trivalent actinides and lanthanides with functional ligands in aqueous solution is of great importance to enrich our knowledge on the fundamental coordination chemistry of trivalent f-block elements and to control the fate of minor actinides in nuclear fuel cycles. In this work, the complexation of Am(III) and Nd(III), representatives for trivalent actinides and lanthanides, respectively, with a N,O-hybrid ligand 6-(dimethylcarbamoyl)picolinic acid (DMAPA, denoted as HL) was investigated by absorption spectroscopy, calorimetry, X-ray crystallography, and density functional theory (DFT) calculations. Successive formation of 1:1, 1:2, and 1:3 (metal/ligand) complexes of Am(III) and Nd(III) with DMAPA was identified, and the corresponding thermodynamic parameters were determined. The binding strength of Am(III) with DMAPA is slightly stronger than that of Nd(III), and the complexation of Nd(III) with DMAPA is mainly entropy-driven. The crystal structure of the 1:2 Nd(III)/DMAPA complex and the DFT calculation shed additional light on the coordination and structural characteristics of the complexes. In contrast to the Nd-N bond in the Nd(III)/DMAPA complex, the Am-N bond in the Am(III)/DMAPA complex exhibits more covalency, which contributes to the slightly stronger complexation of Am(III) with DMAPA.

7.
Molecules ; 27(16)2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-36014431

RESUMEN

Derivates of natural products have been wildly utilized in the treatment of malignant tumors. Isorhamnetin (ISO), a most important active ingredient derived from flavonoids, shows great potential in tumor therapy. However, the therapeutic effects of ISO on gastric cancer (GC) remain unclear. Here, we demonstrate that ISO treatment dramatically inhibited the proliferation of two types of GC cells (AGS-1 and HGC-27) both in vitro and in vivo in time- and dose-dependent manners. These results are consistent with the transcriptomic analysis of ISO-treated GC cells, which yielded hundreds of differentially expressed genes that were enriched with cell growth and apoptosis. Mechanically, ISO treatment initiated the activation of caspase-3 cascade and elevated the expression of mitochondria-associated Bax/Bcl-2, cytosolic cytochrome c, followed by the activation of the cleavage of caspase-3 as well as poly ADP-ribose polymerase (PARP), resulting in the severe reduction of the mitochondrial potential and the accumulation of reactive oxygen species (ROS), while pre-treatment of the caspase-3 inhibitor could block the anti-tumor effect. Therefore, these results indicate that ISO treatment induces the apoptosis of GC cells through the mitochondria-dependent apoptotic pathway, providing a potential strategy for clinical GC therapy.


Asunto(s)
Neoplasias Gástricas , Apoptosis , Caspasa 3/metabolismo , Inhibidores de Caspasas/farmacología , Línea Celular Tumoral , Proliferación Celular , Humanos , Mitocondrias/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Quercetina/análogos & derivados , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Gástricas/metabolismo
8.
Cancer Sci ; 112(11): 4457-4469, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34402138

RESUMEN

Programmed death-ligand 1 (PD-L1) blockade has revolutionized the prognosis of several cancers, but shows a weak effect on pancreatic cancer (PC) due to poor effective immune infiltration. Chemokine C-C motif ligand 21 (CCL21), a chemokine promoting T cell immunity by recruiting and colocalizing dendritic cells (DCs) and T cells, serves as a potential antitumor agent in many cancers. However, its antitumor response and mechanism combined with PD-L1 blockade in PC remain unclear. In our study, we found CCL21 played an important role in leukocyte chemotaxis, inflammatory response, and positive regulation of PI3K-AKT signaling in PC using Metascape and gene set enrichment analysis. The CCL21 level was verified to be positively correlated with infiltration of CD8+ T cells by the CIBERSORT algorithm, but no significant difference in survival was observed in either The Cancer Genome Atlas or the International Cancer Genome Consortium cohort when stratified by CCL21 expression. Additionally, we found the growth rate of allograft tumors was reduced and T cell infiltration was increased, but tumor PD-L1 abundance elevated simultaneously in the CCL21-overexpressed tumors. Then, CCL21 was further verified to increase tumor PD-L1 level through the AKT-glycogen synthase kinase-3ß axis in human PC cells, which partly impaired the antitumor T cell immunity. Finally, the combination of CCL21 and PD-L1 blockade showed superior synergistic tumor suppression in vitro and in vivo. Together, our findings suggested that CCL21 in combination with PD-L1 blockade might be an efficient and promising option for the treatment of PC.


Asunto(s)
Antígeno B7-H1/antagonistas & inhibidores , Quimiocina CCL21/antagonistas & inhibidores , Neoplasias Pancreáticas/terapia , Animales , Antígeno B7-H1/metabolismo , Linfocitos T CD8-positivos/inmunología , Línea Celular Tumoral , Quimiocina CCL21/genética , Quimiocina CCL21/metabolismo , Quimiocina CCL21/fisiología , Quimiotaxis de Leucocito , Células Dendríticas/inmunología , Femenino , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Humanos , Inmunidad Celular , Inflamación , Linfocitos Infiltrantes de Tumor , Ratones , Ratones Endogámicos C57BL , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/mortalidad , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Escape del Tumor , Microambiente Tumoral/inmunología , Regulación hacia Arriba
9.
Ann Surg ; 274(1): 162-169, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32304375

RESUMEN

OBJECTIVE: The aim of this study was to characterize the patterns and treatment of disease recurrence in patients achieving a pathological complete response (pCR) following neoadjuvant chemoradiation for advanced pancreatic ductal adenocarcinoma (PDAC). SUMMARY OF BACKGROUND DATA: A pCR is an independent predictor for improved survival in PDAC. However, disease recurrence is still observed in these patients. METHODS: Patients with advanced PDAC who were treated with neoadjuvant therapy and had a pCR were identified between 2009 and 2017. Overall survival (OS) was determined from the initiation of neoadjuvant, disease-free survival (DFS) from the date of surgery, and post-recurrence survival (PRS) from the date of recurrence. Factors associated with recurrence were analyzed using a Cox-regression model. RESULTS: Of 331 patients with borderline resectable or locally advanced PDAC, 30 achieved a pCR following neoadjuvant treatment and pancreatectomy. The median DFS for pCR patients was 29 months and OS 76 months. Recurrence was observed in 14 patients. No clinicopathologic or treatment characteristics were associated with survival. The median PRS following recurrence was 25 months. Treatment following recurrence included chemotherapy, radiation or ablation, and surgical resection. Hepatectomy or completion pancreatectomy was accomplished in 2 patients that remain alive 13 and 62 months, respectively, following metastasectomy. CONCLUSIONS: A pCR following neoadjuvant therapy in patients with advanced PDAC is associated with remarkable survival, although recurrence occurs in about half of patients. Nevertheless, patients with pCR and recurrence respond well to treatment and survival remains encouraging. Advanced molecular characterization and longitudinal liquid biopsy may offer additional assistance with understanding tumor biologic behavior after achieving a pCR.


Asunto(s)
Carcinoma Ductal Pancreático/terapia , Terapia Neoadyuvante , Neoplasias Pancreáticas/terapia , Anciano , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/cirugía , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Pancreatectomía , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Análisis de Regresión , Inducción de Remisión , Estudios Retrospectivos
10.
HPB (Oxford) ; 23(4): 575-586, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32900612

RESUMEN

BACKGROUND: Lymph node (LN) metastasis is associated with decreased survival following resection for pancreatic ductal adenocarcinoma (PDAC). In N0 disease, increasing total evaluated LN (ELN) correlates with improved outcomes suggesting patients may be understaged when LNs are undersampled. We aim to assess the optimal number of examined lymph nodes (ELN) following pancreatectomy. METHODS: Data from 1837 patients undergoing surgery were prospectively collected. The binomial probability law was utilized to analyze the minimum number of examined LNs (minELN) and accurately characterize each histopathologic stage. LN ratio (LNR) was compared to American Joint Committee on Cancer (AJCC) guidelines. RESULTS: As ELN total increased, the likelihood of finding node positive disease increased. An evaluation based upon the binomial probability law suggested an optimal minELN of 12 for accurate AJCC N staging. As the number of ELNs increased, the discriminatory capacity of alternative strategies to characterize LN disease exceeded that offered by AJCC N stage. CONCLUSION: This is the first study dedicated to optimizing histopathologic staging in PDAC using models of minELN informed by the binomial probability law. This study highlights two separate cutoffs for ELNs depending upon prognostic goal and validates that 12 LNs are adequate to determine AJCC N stage for the majority of patients.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/cirugía , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Estadificación de Neoplasias , Páncreas/patología , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Pronóstico , Tasa de Supervivencia
11.
J Cell Mol Med ; 24(15): 8674-8686, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32643277

RESUMEN

CD73 is a glycosylphosphatidylinositol (GPI)-anchored protein that attenuates tumour immunity via cooperating with CD39 to generate immunosuppressive adenosine. Therefore, CD73 blockade has been incorporated into clinical trials for cancers based on preclinical efficacy. However, the biological role and underlying mechanism of CD73 in pancreatic cancer (PC) microenvironment and its prognostic impact have not been comprehensively studied. In this article, we found that the expression of CD73 was up-regulated in PC tissues and patients with higher CD73 expression had poorer overall survival (OS) and disease-free survival (DFS) in multiple publicly available databases. Higher CD73 expression was significantly associated with its reduced methylation, and only the hypomethylation of CpG site at cg23172664 was obviously correlated with poorer OS. Then, Metascape analysis and GSEA showed that CD73 may play an important role in PC progression and immune regulations. Notably, CD73 was verified to be negatively correlated with infiltrating levels of CD8+ T cells and γδ+ T cells in both TCGA and GEO cohorts via the CIBERSORT algorithm. In addition, patients with higher CD73 expression also tended to have higher PD-L1 expression and tumour mutation load. It seemed that CD73 might be a promising biomarker for the response to the anti-PD-1/PD-L1 treatment in PC. In conclusion, these results reveal that CD73 may function as a promotor in cancer progression and a regulator in immune patterns via CD73-related pathways. Blockade of CD73 might be a promising therapeutic strategy for PC.


Asunto(s)
5'-Nucleotidasa/metabolismo , Biomarcadores de Tumor , Neoplasias Pancreáticas/etiología , Neoplasias Pancreáticas/metabolismo , Escape del Tumor , 5'-Nucleotidasa/genética , Anciano , Anciano de 80 o más Años , Biología Computacional/métodos , Progresión de la Enfermedad , Femenino , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Perfilación de la Expresión Génica , Interacción Gen-Ambiente , Humanos , Proteínas de Punto de Control Inmunitario/genética , Proteínas de Punto de Control Inmunitario/metabolismo , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Masculino , Metilación , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Pronóstico , Análisis de Supervivencia , Transcriptoma , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología
12.
Inorg Chem ; 59(6): 3905-3911, 2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-32133859

RESUMEN

The selective separation of trivalent americium from lanthanides in a nitric acid medium by a tetradentate ligand, N,N'-diethyl-N,N'-ditolyl-2,9-diamide-1,10-phenanthroline (Et-Tol-DAPhen), in an ionic liquid (IL), C4mimNTf2, was studied by batch solvent extraction and spectroscopic approaches. The effect of various parameters such as the contact time, temperature, extractant concentration, and acidity on the extraction of Am3+ and Eu3+ have been evaluated. A significant enhancement in the extraction ability of Et-Tol-DAPhen dissolved in IL was observed as compared to that in molecular diluents under low-acid conditions. The chemical stoichiometry of Am3+ and Eu3+ complexes during extraction was determined to be 1:2 (metal/ligand) by slope analysis of the extraction data. The extraction mechanism of Am3+ and Eu3+ by Et-Tol-DAPhen in IL was determined to be cation exchange on the basis of the effect of nitrate, NTf2-, and C4mim+ ions on extraction. The coordination chemistry of Ln3+ with the ligand in C4mimNTf2 was studied by spectroscopic titrations, which helped to further identify and confirm the extracted species as well as the extraction mechanism. Results from the present study emphasize the unique role of IL in altering the extraction behavior and suggest that the Et-Tol-DAPhen/IL system has potential applications in trivalent actinide/lanthanide separation under low-acid conditions.

13.
Inorg Chem ; 59(1): 161-171, 2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-31498603

RESUMEN

Bis[o-(trifluoromethyl)phenyl]dithiophosphinate is a sulfur-donating ligand capable of providing the largest reported trivalent lanthanide (Ln3+)-actinide (An3+) group separation factors. Literature has shown that the placement and number of the -CF3 functionalities on the aryl rings proximate to the ligating sulfur atoms can significantly impact Ln3+-An3+ extraction and separation factors, but the complexation thermodynamics of -CF3-derivatized aryldithiophosphinates have not been considered to date. This systematic study considers the complexation of three CF3-substituted aryldithiophosphinates-bis(phenyl)dithiophosphinate (LI), [o-(trifluoromethyl)phenyl](phenyl)dithiophosphinate (LII), and bis[o-(trifluoromethyl)phenyl]dithiophosphinate (LIII), with Nd3+ in an ethanolic environment. The chelating ability of NdIII by these ligands follows the order of LIII > LII > LI, which is in line with the reported extraction efficiency. The positive ΔS, as well as positive ΔH, suggests that Nd3+ chelation is entropy-driven and effective desolvation is critical to enabling Nd3+ interaction with otherwise weakly interacting sulfur-containing ligands. Extended X-ray absorption fine structure results confirm thermodynamic investigations and suggest that LI can only form up to 1:2 (M-L) complexes, while LII and LIII form up to 1:3 complexes with Nd3+. All three LIII anions have bidentate interactions with NdIII, but two LII anions have bidentate interactions with Nd3+, while the third LII anion is monodentate. The significant increase in ΔS with each o-CF3 addition suggests aiding desolvation could be central in enabling f-element interaction with weakly interacting donor groups, and this report provides an approach to controlling f-element desolvation as an innovative f-element chelating strategy.

14.
Inorg Chem ; 58(17): 11664-11671, 2019 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-31436978

RESUMEN

Revealing the complexation behavior of high-valent actinides in solutions is of great importance to better understand the fundamental chemistry of actinides as well as to control the separation property of actinides in nuclear fuel cycles. In this work, the complexation of hexavalent actinide cations U(VI), Np(VI), and Pu(VI) with two dipicolinic acid derivatives, 6-(dimethylcarbamoyl)picolinic acid (DMAPA, denoted as HL) and N2,N2,N6,N6-tetramethylpyridine-2,6-dicarboxamide (TMPDA), in aqueous solutions were investigated by absorption spectrophotometry, X-ray crystallography, and DFT calculations. Formation of 1/1 and 1/2 (metal:ligand) complexes of U(VI), Np(VI), and Pu(VI) with DMAPA were identified and the corresponding stability constants were determined. The binding strengths of the three hexavalent actinide cations with DMAPA follow the order of U(VI) > Np(VI) > Pu(VI) in both 1/1 and 1/2 complexes, indicating that the driving force for the complexation is mainly electrostatic interactions. In addition, the relationships between the features of the absorption spectra and the symmetry of Pu(VI) and Np(VI) complexes with DMAPA have been established. The crystal structure of the 1/2 U(VI)/DMAPA complex as well as the DFT optimized structures of An(VI)/DMAPA complexes shed additional light on the structural characters of the hexavalent actinide cation complexes. In contrast to DMAPA, TMPDA exhibits no observable complexation with the three hexavalent actinide cations in aqueous solution, which could be attributed to low electron density on the donor atoms of TMPDA as well as steric hindrance effect by dimethyl carbamoyl groups as elucidated by DFT calculations. The results from this work provide new insights into the complexation trends of hexavalent actinide cations in aqueous solutions.

15.
Inorg Chem ; 58(9): 5457-5467, 2019 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-30335989

RESUMEN

To further reveal the extraction model for selective separation of trivalent actinides over lanthanides by dithiophosphinic acids (DPAHs), five representative DPAH ligands with different substituent groups have been synthesized, and their extraction and complexation behaviors toward Am3+/Eu3+ have been investigated both experimentally and theoretically. The introduction of electron-withdrawing group -CF3 into DPAH ligands is beneficial to their extractability among the five ligands. Slope analyses show that both Am3+ and Eu3+ were extracted as tetra-associated species with DPAH ligands. In addition, the results obtained from luminescence spectroscopy, Raman spectroscopy, and ESI-MS suggest that all of the five DPAHs coordinate with Eu3+ mainly in the form of ML3(HL)(H2O) (L represents deprotonated DPAH). Density functional theory (DFT) calculations on the thermodynamic parameters illustrate that the extractability of DPAHs is dominated by the deprotonation property of these ligands. Meanwhile, molecular orbital analysis indicates that the unoccupied valence orbitals of Am3+ display a stronger affinity to the sulfur lone electron pair than those of Eu3+, which should be one of the key factors contributing to the excellent selectivity of Am3+ over Eu3+ by DPAH ligands.

16.
Inorg Chem ; 58(7): 4420-4430, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30869514

RESUMEN

Recently, phenanthroline-based ligands have received increasing attention due to their excellent separation capabilities for trivalent actinides over lanthanide. In this work, we designed a soft-hard donor combined tetradentate phenanthroline-based extractant, tetraethyl (1,10-phenanthrolin-2,9-diyl)phosphonate (C2-POPhen), for the selective separation of trivalent Am(III) over Ln(III) from HNO3 media. The solvent extraction and complexation behaviors of Am(III) and Ln(III) by C2-POPhen were investigated both experimentally and theoretically. C2-POPhen could selectively extract Am(III) over Eu(III) with an extremely fast extraction kinetics. NMR titration studies suggest that only 1:1 complexes of Ln(III) with C2-POPhen formed in CH3OH in the presence of a significant amount of nitrate, while both 1:1 and 2:1 complexes species could form between C2-POPhen and Ln(III) perchlorate in CH3OH without nitrate ions. The stability constants for the complexation of Am(III) and Ln(III) with C2-POPhen in CH3OH were determined by spectrophotometric titrations and the Am(III) complexes are approximately 1 order of magnitude stronger than those of Ln(III), which is consistent with the extraction results. Theoretical calculations indicate that the Am-N bonds in Am/C2-POPhen complexes possess more covalent characters than the Eu-N bonds in Eu/C2-POPhen complexes, shedding light on the underlying chemical force responsible for the Am/Eu selectivity by C2-POPhen. This work represents the first report utilizing phenanthroline-based phosphonate ligands for selective separation of actinides from highly acidic solutions.

17.
Future Oncol ; 15(30): 3457-3465, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31460788

RESUMEN

Aim: To reassess the prognostic performance of the American Joint Committee on Cancer (AJCC) 8th edition for pancreatic ductal adenocarcinoma (PDAC) and optimize the categorization of PDAC staging. Patients & methods: A total of 11,858 patients with resected PDAC from the Surveillance, Epidemiology and End Results database were retrospectively enrolled by sequential analyses. Results: There was no statistical significance between stage IIA and IIB tumors with hazard ratios of 2.065 and 2.184 (p = 0.620) for stages IIA and IIB, respectively. With the proposed modification, there was a significant difference between the hazard ratios of stages IIIA and IIIB which were 2.481 and 2.715, respectively (p = 0.009). The C-index of modified system was 0.609, slightly higher than AJCC 8th staging system 0.604. Conclusion: We proposed a modified eighth edition of the AJCC staging system by combining stage IIA with IIB and further subclassifying stage III patients in order to lead to better discriminative power.


Asunto(s)
Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/cirugía , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Interpretación Estadística de Datos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Programa de VERF , Tasa de Supervivencia , Adulto Joven
18.
J Transl Med ; 16(1): 294, 2018 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-30359281

RESUMEN

BACKGROUND: The prognosis of pancreatic ductal adenocarcinoma (PDAC) remains poor due to the difficulty of disease diagnosis and therapy. Immunotherapy has had robust performance against several malignancies, including PDAC. In this study, we aim to analyze the expression of CD8 and FoxP3 on T lymphocytes and TGF-ß expression in tumor tissues, and then analyze the possible clinical significance of these finding in order to find a novel effective immunotherapy target in PDAC using a murine model. METHODS: A tissue microarray using patient PDAC samples was stained and analyzed for associations with clinicopathological characteristics. A preclinical murine model administrated with various immunotherapies were analyzed by growth inhibitor, flow cytometry, enzyme-linked immuno sorbent assay and immunohistochemistry. RESULTS: The infiltrating FoxP3+ regulatory T cells (Tregs) in tumor tissues were associated with survival, while CD8+ tumor infiltrating lymphocytes (TILs) were not. Considering the drawbacks of these measure alone, the number of CD8+ and FoxP3+ T cells were combined to create a new estimated value-integrated immune ratio (IIR), which showed excellent validity in survival risk stratification. IIR was further verified as an independent prognostic factor according to multivariate analysis as well as TGF-ß expression. Association between TGF-ß expression and infiltrating Tregs was also verified. Then, in our preclinical murine model, CD25 and TGF-ß combination blockade had a higher tumor growth inhibitor value. This combination therapy significantly depleted periphery and intra-tumor FoxP3+ Tregs while increasing intra-tumor CD8+ TILs levels compared to controls or anti-TGF-ß monotherapy (p < 0.05). Anti-CD25 monotherapy alone also had the ability to deplete periphery and intra-tumor Tregs (p < 0.05). The excretion of intra-tumor IL-10, TGF-ß was notably lower but higher IFN-γ excretion in this combination immunotherapy. Such combination immunotherapy was further confirmed to synergize with anti-PD-1 monotherapy to improve tumor growth inhibition and cure rates. CONCLUSIONS: The combination of CD25, TGF-ß and PD-1 blockade plays a potentially effective role in inhibiting tumor formation and progression. Our results also provide a strong rational strategy for use of IIR in future immunotherapy clinical trials.


Asunto(s)
Subunidad alfa del Receptor de Interleucina-2/antagonistas & inhibidores , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/patología , Factor de Crecimiento Transformador beta/antagonistas & inhibidores , Adenocarcinoma/inmunología , Adenocarcinoma/patología , Adenocarcinoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Animales , Antígeno B7-H1/metabolismo , Linfocitos T CD8-positivos/inmunología , Carcinoma Ductal Pancreático/inmunología , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/terapia , Proliferación Celular , Modelos Animales de Enfermedad , Femenino , Factores de Transcripción Forkhead/metabolismo , Humanos , Inmunoterapia , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Linfocitos Infiltrantes de Tumor/inmunología , Masculino , Ratones Endogámicos C57BL , Persona de Mediana Edad , Análisis Multivariante , Neoplasias Pancreáticas/terapia , Pronóstico , Receptor de Muerte Celular Programada 1/metabolismo , Análisis de Supervivencia , Linfocitos T Reguladores/inmunología , Factor de Crecimiento Transformador beta/metabolismo , Carga Tumoral
19.
Future Oncol ; 14(2): 165-175, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29226705

RESUMEN

AIM: To identify the risk factors for overall survival (OS) of pancreatic ductal adenocarcinoma patients with no distant metastasis, and formulate a novel nomogram for prognostic prediction. PATIENTS & METHODS: Data were obtained from Surveillance, Epidemiology, and End Results database of pancreatic ductal adenocarcinoma patients with no distant metastasis as the primary cohort, and 127 patients at our institution were enrolled as the validation cohort. The prognostic nomogram integrating all independent risk factors for predicting OS was established to achieve superior discriminatory ability. RESULTS: The constructed nomogram showed excellent performance and superior predictive accuracy for OS according to the concordance index and calibration curve. CONCLUSION: One more advanced and accurate predictive model will be obtained to assist in risk stratification via the constructed nomogram.


Asunto(s)
Nomogramas , Neoplasias Pancreáticas/epidemiología , Pronóstico , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Pancreáticas/patología , Factores de Riesgo
20.
Cent Eur J Immunol ; 43(2): 123-131, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30135623

RESUMEN

Previous fundamental or clinical trials of dendritic cell (DC) vaccine against pancreatic ductal adenocarcinoma (PDAC) revealed the burgeoning neoadjuvant immunotherapy. Microarray studies indicated that multiple ingredients of the transfer growth factor beta (TGF-ß) pathway were overexpressed in PDAC, which inhibited the intratumoral immune response. To explore whether the DC volume in tumor microenvironment contributes to the differentiation of T cell cohort and test the hypothesis that combining DC vaccine with TGF-ß inhibitors will elevate the anti-tumor immune response, we managed to co-culture T cells in vitro with pancreatic cancer cells and DCs in different concentrations, and combine TGF-ß blockage with DC vaccine therapy in a murine model of pancreatic cancer. In in vitro studies, we discovered that CD8+ T cytotoxic cell (Tc) presented a significant advantage and lower volume of CD4+ T helper cell (Th) existed with a certain elevated DC concentration (p < 0.05), associated with declined interleukin (IL)-10 and increased interferon (IFN)-γ, which suggested with the DC volume increasing, the enhancing immune effect may represent a great advantage in such a system (p < 0.05). When interfered with anti-TGF-ß antibody or TGF-ß cytokine, respectively, in the co-culture system, we found IFN-γ producing was extremely higher and T cell apoptosis relatively descent with TGF-ß blockage (p < 0.05). The murine PDAC model demonstrated a survival advantage treated with anti-TGF-ß antibody combined with DC vaccine when compared with monotherapy controls (p < 0.05). Therefore, these findings indicated that, through neutralizing TGF-ß associated with DC vaccine, the anti-tumor immunity is highly elevated and this combinational therapy will provide an efficacious prospect.

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