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1.
J Transl Med ; 21(1): 734, 2023 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-37853415

RESUMEN

BACKGROUND AND AIMS: The recurrence and metastasis of hepatocellular carcinoma (HCC) are mainly caused by microvascular invasion (MVI). Our study aimed to uncover the cellular atlas of MVI+ HCC and investigate the underlying immune infiltration patterns with radiomics features. METHODS: Three MVI positive HCC and three MVI negative HCC samples were collected for single-cell RNA-seq analysis. 26 MVI positive HCC and 30 MVI negative HCC tissues were underwent bulk RNA-seq analysis. For radiomics analysis, radiomics features score (Radscore) were built using preoperative contrast MRI for MVI prediction and overall survival prediction. We deciphered the metabolism profiles of MVI+ HCC using scMetabolism and scFEA. The correlation of Radscore with the level of APOE+ macrophages and iCAFs was identified. Whole Exome Sequencing (WES) was applied to distinguish intrahepatic metastasis (IM) and multicentric occurrence (MO). Transcriptome profiles were compared between IM and MO. RESULTS: Elevated levels of APOE+ macrophages and iCAFs were detected in MVI+ HCC. There was a strong correlation between the infiltration of APOE+ macrophages and iCAFs, as confirmed by immunofluorescent staining. MVI positive tumors exhibited increased lipid metabolism, which was attributed to the increased presence of APOE+ macrophages. APOE+ macrophages and iCAFs were also found in high levels in IM, as opposed to MO. The difference of infiltration level and Radscore between two nodules in IM was relatively small. Furthermore, we developed Radscore for predicting MVI and HCC prognostication that were also able to predict the level of infiltration of APOE+ macrophages and iCAFs. CONCLUSION: This study demonstrated the interactions of cell subpopulations and distinct metabolism profiles in MVI+ HCC. Besides, MVI prediction Radscore and MVI prognostic Radscore were highly correlated with the infiltration of APOE+ macrophages and iCAFs, which helped to understand the biological significance of radiomics and optimize treatment strategy for MVI+ HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Estudios Retrospectivos , Invasividad Neoplásica , Apolipoproteínas E/genética
2.
Cancer Cell Int ; 22(1): 128, 2022 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-35305624

RESUMEN

BACKGROUND: While the correlation between PD-L1 expression and KRAS mutation has been previously reported in other solid tumors such as non-small cell lung cancer (NSCLC), whether PD-L1 can be modulated by ERK signaling downstream of KRAS in intrahepatic cholangiocarcinoma (iCCA) and the underlying molecular regulatory mechanism remain unclear. METHODS: The expression of ERK, p-ERK, PD-L1 and autophagy markers following KRAS knockdown or Ras/Raf/MEK/ERK signaling inhibitors treatment was examined in two human iCCA cell lines (HuCCT1 and RBE) using western blotting and immunofluorescence. Both pharmacological autophagy inhibitors and short-interfering RNA against ATG7 were applied to inhibit autophagy. The apoptosis rates of iCCA cell lines were detected by flow cytometry and CCK-8 after co-culturing with CD3/CD28-activated human CD8+ T lymphocytes. Immunohistochemistry was applied to detect the correlation of ERK, p-ERK and PD-L1 in 92 iCCA tissues. RESULTS: The present study demonstrated that the PD-L1 expression level was distinctly reduced in KRAS-mutated iCCA cell lines when ERK signaling was inhibited and ERK phosphorylation levels were lowered. The positive association between p-ERK and PD-L1 was also verified in 92 iCCA tissue samples. Moreover, ERK inhibition induced autophagy activation. Both inhibiting autophagy via autophagy inhibitors and genetically silencing the ATG7 expression partially reversed the reduced PD-L1 expression caused by ERK inhibition. In addition, ERK-mediated down-regulation of PD-L1 via autophagy pathways induced the apoptosis of iCCA cells when co-cultured with CD3/CD28-activated human CD8+ T lymphocytes in vitro. CONCLUSIONS: Our results suggest that ERK signaling inhibition contributes to the reduction of PD-L1 expression through the autophagy pathway in iCCA. As a supplement to anti-PD-1/PD-L1 immunotherapy, ERK-targeted therapy may serve as a potentially novel treatment strategy for human KRAS-mutated iCCA.

3.
Surg Endosc ; 35(2): 910-920, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32748270

RESUMEN

BACKGROUND: The concurrent presence of liver cirrhosis and hepatocellular carcinoma (HCC) poses a challenge for laparoscopic surgeons to establish a routine practice. The aim of this study was to gather evidence and produce recommendations on the safe and effective practice of laparoscopic hepatectomy for patients with solitary HCC (≤ 5 cm) and liver cirrhosis. METHODS: Between October 2013 and October 2014, 356 curative hepatectomies were performed for patients pathologically diagnosed with solitary HCC (≤ 5 cm) accompanied by cirrhosis (stage 4 fibrosis). To overcome selection bias, a 1:2 match using propensity score matching analysis was conducted between laparoscopic and open hepatectomy. Perioperative outcomes were compared between the groups, including hospitalization, operation time, blood loss, and surgical complications. Perioperative inflammation-based markers, including systemic immune-inflammation index (SII), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR) were collected from medical records and analyzed. RESULTS: There were 43 and 77 patients in the laparoscopic and open groups, respectively. The laparoscopic group had less hepatic inflow occlusion (16.3% vs. 61%; P < 0.001), shorter operation time (155 vs. 170 min; P = 0.004), and shorter postoperative hospital stay (4 vs. 7 days; P < 0.001). Although the difference was not significant (P = 0.154), the rate of postoperative complications tended to be lower in the laparoscopic group (2.3%) compared with the open group (9.1%). The increase in postoperative SII, NLR, and LMR for laparoscopic hepatectomy were significantly lower than for open hepatectomy. NLR < 5.8 on postoperative day 3 was significantly correlated with shorter hospital stay (P < 0.001). CONCLUSIONS: Compared with open hepatectomy, laparoscopic hepatectomy for selected HCC patients, even in the presence of cirrhosis, might result in better perioperative outcomes and postoperative inflammatory response attenuation, and ultimately promote faster recovery. This provides evidence for considering routine laparoscopic hepatectomy through careful selection of patients with HCC.


Asunto(s)
Carcinoma Hepatocelular/cirugía , Hepatectomía/métodos , Laparoscopía/métodos , Cirrosis Hepática/cirugía , Neoplasias Hepáticas/cirugía , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Puntaje de Propensión , Estudios Retrospectivos , Resultado del Tratamiento
4.
Br J Cancer ; 123(1): 92-100, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32376890

RESUMEN

BACKGROUND: Immunoscore have shown a promising prognostic value in many cancers. We aimed to establish and validate an immune classifier to predict survival after curative resection of hepatocellular carcinoma (HCC) patients who have undergone curative resection. METHODS: The immunohistochemistry (IHC) classifier assay was performed on 664 patients with Barcelona Clinic Liver Cancer (BCLC) stage 0 or A HCC. A nine-feature-based HCC-IHC classifier was then constructed by the least absolute shrinkage and selection operator method. The associations between the HCC-IHC classifier and patient outcomes were assessed. Herein, a nomogram was generated from the Cox regression coefficients and evaluated by decision curve analysis. RESULTS: We constructed an HCC-IHC classifier based on nine features; significant differences were found between the low-HCC-IHC classifier patients and high-HCC-IHC classifier patients in the training cohort in the 5-year relapse-free survival rates (46.7% vs. 26.7%, respectively; P < 0.001). The HCC-IHC classifier-based nomogram presented better accuracy than traditional staging systems. CONCLUSIONS: In conclusion, the HCC-IHC classifier could effectively predict recurrence in early-stage HCC patients and supplemented the prognostic value of the BCLC staging system. The HCC-IHC classifier may facilitate patient decision-making and individualise the management of postoperative patients with early-stage HCC.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Proteínas de Neoplasias/genética , Recurrencia Local de Neoplasia/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Supervivencia sin Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Inmunohistoquímica/métodos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Pronóstico , Modelos de Riesgos Proporcionales , Tasa de Supervivencia , Transcriptoma/genética
5.
BMC Cancer ; 20(1): 642, 2020 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-32650743

RESUMEN

BACKGROUND: The prognosis of patients with combined hepatocellular carcinoma and intrahepatic cholangiocarcinoma (CHC) is usually poor, and effective adjuvant therapy is missing making it important to investigate whether these patients may benefit from adjuvant transarterial chemoembolization (TACE). We aimed to evaluate the efficiency of adjuvant TACE for long-term recurrence and survival after curative resection before and after propensity score matching (PSM) analysis. METHODS: In this retrospective study, of 230 patients who underwent resection for CHC between January 1994 and December 2014, 46 (18.0%) patients received adjuvant TACE. Univariate and multivariate regression analyses were used to identify the independent predictive factors of survival. Cox regression analyses and log-rank tests were used to compare overall survival (OS) and disease-free survival (DFS) between patients who did or did not receive adjuvant TACE. RESULTS: A total of 230 patients (mean age 52.2 ± 11.9 years; 172 men) were enrolled, and 46 (mean age 52.7 ± 11.1 years; 38 men) patients received TACE. Before PSM, in multivariate regression analysis, γ-glutamyl transpeptidase (γ-GT), tumour nodularity, macrovascular invasion (MVI), lymphoid metastasis, and extrahepatic metastasis were associated with OS. Alanine aminotransferase (ALT), MVI, lymphoid metastasis, and preventive TACE (HR: 2.763, 95% CI: 1.769-4.314, p < 0.001) were independent prognostic factors for DFS. PSM created 46 pairs of patients. Before PSM, adjuvant preventive TACE was not associated with an increased risk of OS (HR: 0.911, 95% CI: 0.545-1.520, p = 0.720) or DFS (HR: 3.345, 95% CI: 1.686-6.638, p = 0.001). After PSM, the 5-year OS and DFS rates were comparable in the TACE group and the non-TACE group (OS: 22.7% vs 14.9%, respectively, p = 0.75; DFS: 11.2% vs 14.4%, respectively, p = 0.06). CONCLUSIONS: The present study identified that adjuvant preventive TACE did not influence DFS or OS after curative resection of CHC.


Asunto(s)
Neoplasias de los Conductos Biliares/mortalidad , Carcinoma Hepatocelular/mortalidad , Quimioembolización Terapéutica/mortalidad , Colangiocarcinoma/mortalidad , Hepatectomía/mortalidad , Neoplasias Hepáticas/mortalidad , Recurrencia Local de Neoplasia/mortalidad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de los Conductos Biliares/patología , Neoplasias de los Conductos Biliares/terapia , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/terapia , Quimioterapia Adyuvante , Colangiocarcinoma/patología , Colangiocarcinoma/terapia , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/terapia , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/terapia , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
6.
EMBO Rep ; 19(5)2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29491006

RESUMEN

Peroxisomes account for ~35% of total H2O2 generation in mammalian tissues. Peroxisomal ACOX1 (acyl-CoA oxidase 1) is the first and rate-limiting enzyme in fatty acid ß-oxidation and a major producer of H2O2 ACOX1 dysfunction is linked to peroxisomal disorders and hepatocarcinogenesis. Here, we show that the deacetylase sirtuin 5 (SIRT5) is present in peroxisomes and that ACOX1 is a physiological substrate of SIRT5. Mechanistically, SIRT5-mediated desuccinylation inhibits ACOX1 activity by suppressing its active dimer formation in both cultured cells and mouse livers. Deletion of SIRT5 increases H2O2 production and oxidative DNA damage, which can be alleviated by ACOX1 knockdown. We show that SIRT5 downregulation is associated with increased succinylation and activity of ACOX1 and oxidative DNA damage response in hepatocellular carcinoma (HCC). Our study reveals a novel role of SIRT5 in inhibiting peroxisome-induced oxidative stress, in liver protection, and in suppressing HCC development.


Asunto(s)
Acil-CoA Oxidasa/antagonistas & inhibidores , Acil-CoA Oxidasa/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Estrés Oxidativo , Sirtuinas/metabolismo , Acil-CoA Oxidasa/genética , Animales , Daño del ADN , Regulación hacia Abajo , Femenino , Técnicas de Silenciamiento del Gen , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Peróxido de Hidrógeno , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Oxidación-Reducción , Peroxisomas/química , Pronóstico , Sirtuinas/genética
7.
Cancer Immunol Immunother ; 68(8): 1369-1378, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31338558

RESUMEN

Intrahepatic cholangiocarcinoma (ICC) is a rare malignancy with poor prognosis. The evaluation of recurrence risk after liver resection is of great importance for ICCs. We aimed to assess the prognostic value of intra- and peritumoral immune infiltrations and to establish a novel histopathology-related immunoscore (HRI) associated with ICC recurrence. A total of 280 ICC patients who received curative resection between February 2005 and July 2011 were enrolled in our study. Patients were randomly assigned to the derivation cohort (n = 176) or the validation cohort (n = 104). Sixteen immune biomarkers in both intra- and peritumoral tissues were examined by immunohistochemistry. The least absolute shrinkage and selection operator (LASSO) Cox model was used to establish the HRI score. Cox regression analysis was used for multivariate analysis. Nine recurrence-related immune features were identified and integrated into the HRI score. The HRI score was used to categorize patients into low-risk and high-risk groups using the X-tile software. Kaplan-Meier analysis presented that the HRI score showed good stratification between low-risk and high-risk groups in both the derivation cohort (P < 0.001) and the validation cohort (P = 0.014), respectively. Multivariate analysis demonstrated that serum γ-glutamyl transpeptidase, carbohydrate antigen 19-9, lymphoid metastasis, tumor numbers, and the HRI score were independent risk factors associated with recurrence-free survival (RFS). The combination of Shen's model and HRI score provided better performance in recurrence prediction compared with traditional staging systems. The HRI score might serve as a promising RFS predictor for ICC with prognostic values.


Asunto(s)
Antígenos de Carbohidratos Asociados a Tumores/metabolismo , Biomarcadores de Tumor/metabolismo , Colangiocarcinoma/diagnóstico , Neoplasias Hepáticas/diagnóstico , Hígado/metabolismo , Colangiocarcinoma/mortalidad , Colangiocarcinoma/patología , Estudios de Cohortes , Femenino , Hepatectomía , Humanos , Hígado/patología , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Pronóstico , Proyectos de Investigación , Análisis de Supervivencia , Carga Tumoral , gamma-Glutamiltransferasa/metabolismo
8.
BMC Med ; 17(1): 106, 2019 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-31164128

RESUMEN

BACKGROUND: Intratumoral immune infiltrates have manifested a robust prognostic signature in patients with hepatocellular carcinoma (HCC). We hypothesized that a novel tissue-related immune signature (TRIS) could improve the prediction of postoperative survival for patients diagnosed with early/intermediate HCC. METHODS: Twenty-eight immune features were immunohistochemically examined on 352 HCC specimens. The LASSO Cox regression model was used to construct a five-feature-based TRIS. The univariate and multivariate Cox analyses were performed. Based on independent predictors, the immune-clinical prognostic index (ICPI) was established. Performance assessment was measured with C-index and compared with seven traditional staging systems. The independent validation cohort (n = 393) was included to validate the model. RESULTS: By using the LASSO method, the TRIS were constructed on the basis of five immune features, CD3intratumoral (T), CD27T, CD68peritumoral (P), CD103T, and PD1T. Multivariate Cox analysis showed that the TRIS was an independent prognostic predictor. In the training cohort, γ-glutamyl transferase, tumor diameter, tumor differentiation, and TRIS were incorporated into the ICPI. The ICPI presented satisfactory discrimination ability, with C-index values of 0.691 and 0.686 in the training and validation cohorts, respectively. Compared with seven conventional staging systems (C-index, training cohort, 0.548-0.597; validation cohort, 0.519-0.610), the ICPI exhibited better performance for early/intermediate-stage HCCs. Further, the patients were categorized into three subgroups with X-tile software, and the stratified ICPI presented a superior corrected Akaike information criterion and homogeneity in both cohorts. CONCLUSIONS: Our ICPI was a useful and reliable prognostic tool which may offer good individualized prediction capability for HCC patients with early/intermediate stage.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico , Inmunofenotipificación , Neoplasias Hepáticas/diagnóstico , Linfocitos Infiltrantes de Tumor/metabolismo , Adulto , Anciano , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Estudios de Cohortes , Femenino , Humanos , Inmunohistoquímica , Inmunofenotipificación/métodos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Linfocitos/patología , Linfocitos Infiltrantes de Tumor/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Análisis de Supervivencia , Análisis de Matrices Tisulares , Transcriptoma
9.
Cancer Cell Int ; 19: 71, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30962765

RESUMEN

BACKGROUND: Oxaliplatin-based chemotherapy is widely used to treat hepatocellular carcinoma (HCC). Recent studies suggested that therapeutic resistance of tumors was affected by tumor microenvironment (TME). As a major component of TME, the role of tumor-associated macrophages (TAMs) on drug resistance in HCC is largely unknown. METHODS: 26 HCC samples were obtained from patients who had underwent transarterial chemoembolization (TACE) within 3 months before receiving curative resections. Immunohistochemistry was applied to detect the density of TAMs in these tissues. SMMC-7721 and Huh-7 cell lines were used to co-culture with THP-1 derived macrophages. Under oxaliplatin treatment, cell death was measured using MTT and annexin V/propidium iodide assays. Autophagy activation was evaluated by GFP-LC3 redistribution and LC3 conversion in SMMC-7721 and Huh-7. Short-interfering RNA against ATG5 gene was applied to inhibit autophagy. In vivo validation was conducted in Huh-7 with or without macrophages using an HCC xenograft model in nude mice after oxaliplatin administration. RESULTS: We found that the density of TAMs in HCC samples was associated with the efficacy of TACE. Macrophages inhibited cell death induced by oxaliplatin in HCC cells. Autophagy was functionally activated in HCC cells after co-culturing with macrophages. Suppression of autophagy using RNA interference of ATG5 in HCC cells promoted the oxaliplatin cytotoxicity in the co-culture system. Critically, co-implantation with macrophages in HCC xenografts weakens cytotoxic effect of oxaliplatin through inducing autophagy to avoid apoptosis. CONCLUSIONS: Our results suggest that TAMs induce autophagy in HCC cells which might contribute to oxaliplatin resistance. Targeting TAMs is a promising therapeutic strategy to enhance the effects of chemotherapy oxaliplatin in HCC patients.

10.
Small ; 14(27): e1702054, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29845726

RESUMEN

An approach to assemble hierarchically ordered 3D arrangements of curved graphenic nanofragments for energy storage devices is described. Assembling them into well-defined interconnected macroporous networks, followed by removal of the template, results in spherical macroporous, mesoporous, and microporous carbon microball (3MCM) architectures with controllable features spanning nanometer to micrometer length scales. These structures are ideal porous electrodes and can serve as lithium-ion battery (LIB) anodes as well as capacitive deionization (CDI) devices. The LIBs exhibit high reversible capacity (up to 1335 mAh g-1 ), with great rate capability (248 mAh g-1 at 20 C) and a long cycle life (60 cycles). For CDI, the curved graphenic networks have superior electrosorption capacity (i.e., 5.17 mg g-1 in 0.5 × 10-3 m NaCl) over conventional carbon materials. The performance of these materials is attributed to the hierarchical structure of the graphenic electrode, which enables faster ion diffusion and low transport resistance.

11.
Acta Pharmacol Sin ; 39(2): 243-250, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28905937

RESUMEN

Aberrant fibroblast growth factor receptor (FGFR) activation is found across a diverse spectrum of malignancies, especially those lacking effective treatments. SOMCL-085 is a novel FGFR-dominant multi-target kinase inhibitor. Here, we explored the FGFR-targeting anticancer activity of SOMCL-085 both in vitro and in vivo. Among a panel of 20 tyrosine kinases screened, SOMCL-085 potently inhibited FGFR1, FGFR2 and FGFR3 kinase activity, with IC50 values of 1.8, 1.9 and 6.9 nmol/L, respectively. This compound simultaneously inhibited the angiogenesis kinases VEGFR and PDGFR, but without obvious inhibitory effect on other 12 tyrosine kinases. In 3 representative human cancer cell lines with different mechanisms of FGFR activation tested, SOMCL-085 (20-500 nmol/L) dose-dependently inhibited FGFR1-3 phosphorylation and the phosphorylation of their key downstream effectors PLCγ and Erk. In 7 FGFR aberrant human cancer cell lines, regardless of the mechanistic complexity of FGFR over-activation, SOMCL-085 potently inhibited FGFR-driven cell proliferation by arresting cells at the G1/S phase. In the FGFR1-amplified lung cancer cell line H1581 xenograft mice and FGFR2-amplified gastric cancer cell line SNU16 xenograft mice, oral administration of SOMCL-085 (25, 50 mg·kg-1·d-1) for 21 days substantially suppressed tumor growth without affecting their body-weight. These results suggest that SOMCL-085 is a potent multi-target FGFR inhibitor that inhibits the FGFR-dependent neoplastic phenotypes of human cancer cells in vitro and in vivo.


Asunto(s)
Antineoplásicos/uso terapéutico , Naftalenos/uso terapéutico , Piperazinas/uso terapéutico , Piridinas/uso terapéutico , Receptores de Factores de Crecimiento de Fibroblastos/antagonistas & inhibidores , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Línea Celular Tumoral , Femenino , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Ratones Desnudos , Naftalenos/administración & dosificación , Naftalenos/farmacología , Piperazinas/administración & dosificación , Piperazinas/farmacología , Piridinas/administración & dosificación , Piridinas/farmacología , Receptores del Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Receptores de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos
12.
J Nanosci Nanotechnol ; 18(1): 459-462, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29768870

RESUMEN

The luminescence properties of Eu2+-activated SrSi2N2O2 phosphor under VUV excitation have been firstly studied in this work. Normal pressure (1 atm) and high pressure (5 atm) synthesized- Sr0.96Si2N2O2:Eu+0.042+ powders were prepared by solid state reaction at temperature between 1400 °C and 1600 °C under 5% H2-95% N2 atmosphere and 5 atm N2 atmosphere, respectively. XRD patterns show that the purity and crystallinity of 1 atm-Sr0.96Si2N2O2:Eu+0.042+ is better than that of 5-atm Sr0.96Si2N2O2:Eu0.042+. Green emission broad band at 541 nm with Full Width at Half Maximum (FWHM) of 75 nm can be efficiently excited under 172 nm. The luminescent intensity of 1 atm-Sr0.96Si2N2O2:Eu0.042+ is almost two folds than that of 5-atm Sr0.96Si2N2O2:Eu0.042+. Moreover, photoluminescent spectra of Sr0.96Si2N2O2:Eu0.042+ with 10 K to 300 K were also carried out in this study. SrSi2N2O2:Eu2+ phosphor is a new and promising green phosphor for VUV applications.

13.
J Nanosci Nanotechnol ; 18(1): 374-380, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29768856

RESUMEN

We synthesized a emission tunable Eu(II)-activated SrAl2Si2O8 phosphors Eu(II)-activated SrAl2Si2O8 phosphors. The emission color could be controlled from blue to greenish-blue emissions via changing Sr/Eu ratio. The SrAl2Si2O8 and EuAl2Si2O8 phases were found to form a complete solid solution with composition of (Sr1-xEux)Al2Si2O8 (0 ≤ x ≤ 1.0), as indicated by X-ray diffraction analysis. Our research results also reveal that the use of fluxing agents of H3BO3 or LiBO2 in the materials synthesis plays a crucial role in improving the photoluminescence (PL) properties of (Sr,Eu)Al2Si2O8 phosphor and the surface morphology. The SrAl2Si2O8:Eu phosphors with varied Eu2+ contents show typical broad band emission in the range of 409 to 492 nm under ultraviolet excitation ranging from 352 to 380 nm. As indicated by the PL spectra of (Sr1-xEux)Al2Si2O8, the emission wavelength was found to red-shift, whereas the PL intensity was found to decrease with increasing doped Eu2+ content. Wide-range Commission Internationale de I'Eclairage (CIE) chromaticity coordinates from (0.15, 0.06) (when x = 0) to (0.23, 0.30) (when x = 1.0) can be achieved by properly adjusting the doped Eu2+ content in (Sr1-xEux)Al2Si2O8 phases. The optimization of preparation, correlation between crystal structure and luminescence properties, and microstructure of Eu2+-activated SrAl2Si2O8 are presented.

14.
J Nanosci Nanotechnol ; 18(1): 3-10, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29768804

RESUMEN

Ba3Y(BO3)3:Eu3+, Bi3+ were successfully prepared via a solid-state reaction. The crystallinity, photoluminescence properties, energy transfer and thermal quenching properties were studied. Subjecting Ba3Y(BO3)3:Bi3+ samples to different excitation wavelengths (340-370 nm), obtained blue and green emission ascribed to Bi3+(II) and Bi3+(I) sites, respectively. The influence of these two sites were systematically investigated. Bi3+ efficiently transferred its absorbed energy to neighboring Eu3+ sites by enhancing its luminescence intensity. Moreover, Bi3+ greatly enhanced the excitation spectra of Eu3+ in the N-UV region by 2.26 times which indicates that Ba3Y(BO3)3:Eu3+, Bi3+ can be used as a phosphor for w-LEDs using N-UV LED chips.

15.
J Nanosci Nanotechnol ; 18(1): 68-74, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29768813

RESUMEN

Li-rich layered cathode materials, Li1.2Ni0.4-xAlxMn0.6O2.2-y Cly (0 ≤ x ≤ 0.03 and 0 ≤ y ≤ 0.03), were successfully synthesized through coprecipitation, and the effects of Al3+-Cl- co-substitution on their surface morphology, crystal structure, surface chemistry, and electrochemical performance were characterized through XRD, SEM, XPS, TEM, and electrochemical and charge-discharge cycling. Doping the cathodes with Al3+ and Cl- ions enhanced electrochemical performance at room temperature and at a high working temperature of 55 °C. The as-synthesized optimal composition was Li1.2Ni0.37Al0.03Mn0.6O2.17Cl0.03. The discharge capacity demonstrated high cycle retention at 55 °C. XPS analyses revealed that Al3+-Cl- co-substitution enhanced the structural stability of the cathode materials by forming strong Mn-O and Ni-O bonds. Moreover, compared with un-doped cathode materials, the impedance of Al3+-Cl--codoped cathode materials was drastically reduced by 52.2%. The results indicated that Al3+-Cl--codoped Li-excess cathodes deliver a high cycle performance at high temperatures.

16.
J Nanosci Nanotechnol ; 18(1): 127-131, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29768824

RESUMEN

Lithium-Sulfur (Li-S) batteries have been achieved great attention in recent years owing to its high theoretical capacity (1675 mAh/g) and energy density (2600 Wh/kg). PEG embedded MnO2/Sulfur composite was prepared via solid state reaction method. The composite was characterized by Transmission electron microscopy, scanning electron microscopy and X-ray diffractometer. MnO2 effectively suppress the diffusion of polysulfides and add a mechanical strength to the electrode. PEG binds the MnO2 and S, resulting in the minimization of active material loss and improves the electrochemical performance in lithium sulfur batteries. The PEG/MnO2/Sulfur composite exhibits discharge capacity of 647 mAh/g even after 30 cycles with appreciable sustainability. Therefore, the resulting PEG/MnO2/Sulfur composite exhibited as a desirable cathode material for Li-S battery.

17.
J Nanosci Nanotechnol ; 18(1): 215-222, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29768833

RESUMEN

The present study emphases on the effect of toting of TiO2 filler on the electrochemical enactment of polymer electrolyte containing PVdF-co-HFP(30) + SEt3TFSI(10) + EC/PC(60) + TiO2(x) wt% (Poly (vinylidene fluoride-co-hexafluoropropylene + Triethylsulfoniumbis(trifluoromethylsulfonyl)imide + Ethylene carbonate/Propylene carbonate (1:1 ratio) + Titanium dioxide) for lithium battery applications. Composite electrolytes with different weight percentages of TiO2 were prepared and characterized by different surface analytical, thermal and electrochemical techniques. With gradual increase of the amount of TiO2 upto 6 wt%, broadening of the prominent peak has been noted, suggesting a decrease in the degree of crystallinity upon the addition of TiO2, as revealed by X-ray diffraction (XRD). Raman and FT-IR studies confirm the presence of various functional groups, present in the matrix. The electrolyte with TiO2 (6 wt%) has maximum stability of 460 °C, as confirmed by thermal analysis. Conductivity of the composite polymer electrolytes increases upto 6 wt% of TiO2 (3.42 × 10-3 S/cm at 303 K) and further addition, causes a dip down in conductivity, indicating an improvement in the ionic conductivity and thermal stability with the incorporation of TiO2 filler. Surface morphologic images show the presence of surface and cavity in the polymer matrix, filled with the filler uniformly. Voltammetric studies confirm the electrochemical stability of films upto 4.62 V. Coin cell containing Li anode and LiFePO4 cathode along with polymer electrolyte/6 wt% TiO2 filler, delivers a first discharge capacity of 145 mAh/g with the working voltage of 3.4 V.

18.
J Nanosci Nanotechnol ; 18(1): 368-373, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29768855

RESUMEN

The crystalline Zirconium oxide (ZrO2) nano particles were synthesized using optimized content of Zirconium nitrate (Zr(NO3)2·3H2O) with varying KOH concentration (0.5, 1 and 1.5 M) by co-precipitation method. The thermal history of the precursor was carefully analyzed through Thermogravimetric (TG/DTA) measurement. The as prepared samples were characterized to ensure structural, functional, morphological, compositional, chemical composition and band gap by X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), Laser Raman, scanning electron microscopy (SEM), High resolution Transverse Electron Microscopy (HR-TEM), X-ray photo electron spectroscopy (XPS), EDX, Photo luminescence spectroscopy (PL). The monoclinic structure with space group P21/c has been confirmed from XRD (JCPDS 89-9066). The Zr-O stretching vibration and Zr-O2-Zr bending vibrations were confirmed through FTIR analysis. The well dispersed particles with spherical morphology were confirmed through SEM and TEM analysis. The oxidation states of Zr, O and C were confirmed through XPS analysis. The oxygen vacancies and band gap of the particles were investigated through PL analysis.

19.
J Nanosci Nanotechnol ; 18(1): 296-300, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29768843

RESUMEN

In this study, we first focus on effects of PVA surfactant on Li2Fe0.5Mn0.5SiO4/C by using X-ray diffraction, Fourier transform infrared spectroscopy, micro Raman analysis, scanning electron microscope, transmission electron microscope and magnetization measurements. XRD result reveals the formation of new phase (Li2Fe0.5Mn0.5SiO4/C), as a result of embedded carbon, intensity of the peaks was also suppressed. Intensity domination of G-band in micro Raman analysis affirmed that the establishment of graphene formation which was yielded from decomposition of organic materials of both PVA and acetate. Confirmation of Si-O and Si-C bond in the as-prepared material was made by FTIR analyses. A well uniform spherical shaped morphology was observed in both SEM and TEM images. In addition, the TEM picture further demonstrates Li2Fe0.5Mn0.5SiO4/C with average particle size of about 20 nm by PVA introducing.

20.
J Nanosci Nanotechnol ; 18(1): 121-126, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29768823

RESUMEN

A sulfur-Polyacrylonitrile (PAN)-acetylene black (AB) composite was synthesized via thermal treatment processes. The as-prepared ternary composite was characterized by expending transmission electron microscopy (TEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) and electrochemical investigations. The improved electrochemical performance can be attributed to the formation of PAN layer, which can keep a tight contact between carbon and sulfur which leads to improve the conductivity. Moreover, the PAN can also act as a flexible cushion to accommodate volume changes of sulfur cathode as well as a barrier to trap soluble polysulfide intermediates during the charge-discharge process. The PAN-S-AB composite exhibits discharge capacity of 620 mAh/g even after 50 cycles with appreciable sustainability. Therefore, the resulting PAN/S/AB composite exhibited as a desirable cathode material for Li-S battery with great performance.

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