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2.
J Crit Care ; 79: 154441, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37812993

RESUMO

BACKGROUND: Venous congestion has been demonstrated to increase the risk of acute kidney injury (AKI) after cardiac surgery. Although many surrogate markers for venous congestion are currently used in clinical settings, there is no consensus on which marker is most effective in predicting AKI. METHODS: We evaluated various markers of venous congestion, including central venous pressure (CVP), inferior vena cava (IVC) diameter, portal pulsatility fraction (PPF), hepatic vein flow pattern (HVF), intra-renal venous flow pattern (IRVF), and venous excess ultrasound grading score (VExUS) in adult patients undergoing cardiac surgery to compare their ability in predicting AKI. RESULTS: Among the 230 patients enrolled in our study, 53 (23.0%) developed AKI, and 11 (4.8%) required continuous renal replacement therapy (CRRT). Our multivariate logistic analysis revealed that IRVF, PPF, HVF, and CVP were significantly associated with AKI, with IRVF being the strongest predictor (odds ratio [OR] 2.27; 95% confidence interval [CI], 1.38-3.73). However, we did not observe any association between these markers and CRRT. CONCLUSION: Venous congestion is associated with AKI after cardiac surgery, but not necessarily with CRRT. Among the markers tested, IRVF exhibits the strongest correlation with AKI.


Assuntos
Injúria Renal Aguda , Procedimentos Cirúrgicos Cardíacos , Hiperemia , Adulto , Humanos , Estudos de Coortes , Injúria Renal Aguda/etiologia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Biomarcadores
3.
Cancer Lett ; 503: 19-31, 2021 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-33472090

RESUMO

Tumor-associated mesenchymal stem cells (MSCs) play a critical role in the growth and metastasis of hepatocellular carcinoma (HCC). However, the mechanism underlying the crosstalk between MSCs and HCC cells is not completely understood. Here, HCC cells were treated with or without conditioned medium of MSCs (CM-MSC), and examined for differential expression of long non-coding RNAs (lncRNAs). Knockdown and overexpression experiments were conducted to explore the function of the lncRNA DNM3OS in MSC-induced HCC growth and metastasis. CM-MSC treatment led to a concentration-dependent induction of DNM3OS in HCC cells. DNM3OS was significantly upregulated in HCC compared to adjacent liver tissues. High DNM3OS expression was associated with TNM stage, vascular invasion, and poor prognosis of HCC patients. Silencing of DNM3OS inhibited HCC cell proliferation and invasion in vitro and tumorigenesis and metastasis in vivo. Overexpression of DNM3OS enhanced HCC cell proliferation, invasion, and metastasis. Biochemically, DNM3OS was mainly localized in the nucleus and physically interacted with KDM6B. The association of DNM3OS with KDM6B induced the expression of TIAM1 through reduction of H3K27me3 at the TIAM1 promoter. TIAM1 overexpression restored the proliferation and invasion of DNM3OS-depleted HCC cells. Our data delineate a mechanism by which MSCs accelerate HCC growth and metastasis through a DNM3OS/KDM6B/TIAM1 axis.


Assuntos
Carcinoma Hepatocelular/patologia , Histona Desmetilases com o Domínio Jumonji/genética , Neoplasias Hepáticas/patologia , Células-Tronco Neoplásicas/química , RNA Longo não Codificante/genética , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T/genética , Animais , Carcinoma Hepatocelular/genética , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Meios de Cultivo Condicionados/química , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Neoplasias Hepáticas/genética , Masculino , Camundongos , Metástase Neoplásica , Transplante de Neoplasias
4.
Artigo em Inglês | MEDLINE | ID: mdl-32700465

RESUMO

Lung cancer is considered to cause the most cancer-related deaths worldwide. Due to the deficiency in early-stage diagnostics and local invasion or distant metastasis, the first line of treatment for most patients unsuitable for surgery is chemotherapy, targeted therapy or immunotherapy. Nanocarriers with the function of improving drug solubility, in vivo stability, drug distribution in the body, and sustained and targeted delivery, can effectively improve the effect of drug treatment and reduce toxic and side effects, and have been used in clinical treatment for lung cancer and many types of cancers. Here, we review nanoparticle (NP) formulation for lung cancer treatment including liposomes, polymers, and inorganic NPs via systemic and inhaled administration, and highlight the works of overcoming drug resistance and improving cancer immunotherapy. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.


Assuntos
Neoplasias Pulmonares , Nanopartículas , Neoplasias , Sistemas de Liberação de Medicamentos , Resistência a Medicamentos , Humanos , Imunoterapia , Neoplasias Pulmonares/tratamento farmacológico , Nanomedicina , Neoplasias/tratamento farmacológico
5.
Gland Surg ; 9(4): 1026-1035, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32953611

RESUMO

BACKGROUND: Neoadjuvant chemotherapy (NAC) has become the best comprehensive treatment choice for breast cancer. Epirubicin is a crucial drug widely used in breast cancer chemotherapy, but it is often used with a reduced dosage in NAC for Chinese patients for its notable cardiotoxicity and frequent adverse events. This study aimed to investigate the efficacy and safety of standard-dose epirubicin in NAC for Chinese breast cancer patients retrospectively. METHODS: We retrospectively collected clinicopathological parameters of breast cancer patients who underwent epirubicin-based NAC and a later surgery from three separate medical centers. Patients were divided into standard-dose and low-dose groups according to the epirubicin dose. The pathological complete response (pCR) rate, as the main therapeutic outcomes, and the incidence of adverse events were recorded and compared. RESULTS: The pCR rate of the standard-dose group was 41.2%, while the low-dose group was 10.1% (P<0.001). The univariate analysis showed that ER status (HR, 2.519; 95% CI, 1.057-5.988, P=0.037) and epirubicin dose (HR, 6.200; 95% CI, 2.374-16.193, P<0.001) were associated with pCR rates. The multivariate analysis showed that patients receiving standard-dose epirubicin chemotherapy (HR, 6.925; 95% CI, 2.537-18.902, P<0.001) showed more possibility to achieve pCR after NAC. There was no significant difference in the incidence rates of grade III/IV adverse events between these two different dose groups. CONCLUSIONS: Standard-dose epirubicin increases the pCR rate in breast cancer patients treated with NAC, and no other toxicity is noted.

6.
J Magn Reson Imaging ; 52(1): 231-245, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31867839

RESUMO

BACKGROUND: In pancreatic cancer, methods to predict early recurrence (ER) and identify patients at increased risk of relapse are urgently required. PURPOSE: To develop a radiomic nomogram based on MR radiomics to stratify patients preoperatively and potentially improve clinical practice. STUDY TYPE: Retrospective. POPULATION: We enrolled 303 patients from two medical centers. Patients with a disease-free survival ≤12 months were assigned as the ER group (n = 130). Patients from the first medical center were divided into a training cohort (n = 123) and an internal validation cohort (n = 54). Patients from the second medical center were used as the external independent validation cohort (n = 126). FIELD STRENGTH/SEQUENCE: 3.0T axial T1 -weighted (T1 -w), T2 -weighted (T2 -w), contrast-enhanced T1 -weighted (CET1 -w). ASSESSMENT: ER was confirmed via imaging studies as MRI or CT. Risk factors, including clinical stage, CA19-9, and radiomic-related features of ER were assessed. In addition, to determine the intra- and interobserver reproducibility of radiomic features extraction, the intra- and interclass correlation coefficients (ICC) were calculated. STATISTICAL TESTS: The area under the receiver-operator characteristic (ROC) curve (AUC) was used to evaluate the predictive accuracy of the radiomic signature in both the training and test groups. The results of decision curve analysis (DCA) indicated that the radiomic nomogram achieved the most net benefit. RESULTS: The AUC values of ER evaluation for the radiomics signature were 0.80 (training cohort), 0.81 (internal validation cohort), and 0.78 (external validation cohort). Multivariate logistic analysis identified the radiomic signature, CA19-9 level, and clinical stage as independent parameters of ER. A radiomic nomogram was then developed incorporating the CA19-9 level and clinical stage. The AUC values for ER risk evaluation using the radiomic nomogram were 0.87 (training cohort), 0.88 (internal validation cohort), and 0.85 (external validation cohort). DATA CONCLUSION: The radiomic nomogram can effectively evaluate ER risks in patients with resectable pancreatic cancer preoperatively, which could potentially improve treatment strategies and facilitate personalized therapy in pancreatic cancer. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2020;52:231-245.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias Pancreáticas , Feminino , Humanos , Masculino , Nomogramas , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/cirurgia , Reprodutibilidade dos Testes , Estudos Retrospectivos
7.
Pancreatology ; 20(1): 95-100, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31786057

RESUMO

OBJECTIVES: FOLFIRINOX (FFX) or abraxane plus gemcitabine (AG)-based chemotherapy is used widely as firstline treatment for patients with pancreatic cancer. However, their use in the elderly is discouraged because of adverse events. More clinical data about the therapeutic response and tolerability to FFX or AG in elderly patents (over 70 years old) are required. METHODS: Patients with advanced pancreatic cancer (n = 203; 131 metastatic pancreatic cancer patients (MPC) and 72 locally advanced pancreatic cancer patients (LAPC)) were treated using modified-FFX (mFFX) or AG and mFFX sequentially. The patients were grouped according to their age, patients below 70 years old and patients above 70 years old. The objective response rate (ORR), disease control rate (DCR), progression free survival (PFS), overall survival (OS) and adverse events were compared between the groups. RESULTS: The ORRs in the elderly and in patients below 70 were similar (30.0% versus 32.3%). The median OS and PFS were also similar between the groups (mOS 13.3 m vs 12.7 m, p = 0.729, HR 0.874 (95% CI 0.5310 to 1.438); mPFS mPFS 10.6 m vs 10.3 m, p = 0.363, HR 0.800 (95% CI 0.4954 to 1.293)). However, the elderly patients suffered a higher incidence of severe adverse events (50% vs. 28.3%). CONCLUSIONS: These data could provide guidance for chemotherapy use in elderly patients with advanced pancreatic cancer. Age did not affect treatment outcome; however, supportive treatment is very important for elderly patients receiving chemotherapy.


Assuntos
Paclitaxel Ligado a Albumina/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Desoxicitidina/administração & dosagem , Desoxicitidina/uso terapêutico , Fluoruracila/uso terapêutico , Humanos , Irinotecano/uso terapêutico , Leucovorina/uso terapêutico , Oxaliplatina/uso terapêutico , Gencitabina
8.
Cell Oncol (Dordr) ; 42(6): 769-781, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31256347

RESUMO

PURPOSE: Peroxiredoxin 4 (PRDX4) has been reported to play a dual role in the progression of hepatocellular carcinoma (HCC). As yet, however, the underlying molecular mechanism has not been fully elucidated. METHODS: We examined the effects of PRDX4 on the growth and survival of HCC cells in an anchorage-independent microenvironment. The regulation of ß-catenin stability and activity by PRDX4 was investigated. RESULTS: We found that PRDX4 depletion reduced, and PRDX4 overexpression increased, both anchorage-dependent and anchorage-independent growth of HCC cells. We also found that PRDX4 depletion caused an overproduction of reactive oxygen species (ROS) in HCC cells, especially under suspension conditions. PRDX4 knockdown predisposed HCC cells to anoikis, whereas PRDX4 overexpression induced resistance to anoikis. Subsequent in vivo studies confirmed that PRDX4 deficiency blocks HCC tumor growth and pulmonary metastasis. Mechanistically, we found that RDX4 reduced ß-TrCP-mediated ß-catenin ubiquitination and enhanced ß-catenin protein stability, consequently leading to activation of ß-catenin signaling. Silencing of ß-catenin impaired PRDX4-mediated anchorage-independent growth and survival, whereas ß-catenin overexpression increased the survival and growth of PRDX4-depleted cells under anchorage-independent conditions. Further investigation revealed that the ß-catenin downstream gene ID2 is responsible for the oncogenic activity of PRDX4 in HCC cells, promoting anchorage-independent growth and anoikis resistance. CONCLUSIONS: PRDX4 reduces anoikis and promotes tumorigenesis and metastasis of HCC cells through stabilization of the ß-catenin protein and upregulation of ID2. Targeting of PRDX4 may represent a promising strategy to block HCC cell growth and metastasis.


Assuntos
Anoikis , Carcinoma Hepatocelular/patologia , Proteína 2 Inibidora de Diferenciação/metabolismo , Neoplasias Hepáticas/patologia , Peroxirredoxinas/metabolismo , Transdução de Sinais , beta Catenina/metabolismo , Animais , Carcinogênese/patologia , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Resistencia a Medicamentos Antineoplásicos , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica , Estabilidade Proteica , Ubiquitinação
9.
Ther Adv Med Oncol ; 11: 1758835919850665, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31205511

RESUMO

BACKGROUND: Non-small cell lung carcinoma (NSCLC) is a major worldwide health threat due to its low cure rate and high lethality. Emerging evidence suggests that epidermal growth factor receptor (EGFR) plays vital roles in cancer initiation and progression, and is considered an important cancer-driving protein. However, how EGFR expression is regulated during NSCLC development remains to be fully elucidated. METHODS: In NSCLC clinical samples, EGFR protein levels were measured by western blotting and qRT-PCR, respectively. Combining microRNA (miRNA) target prediction software and the pulldown assay, we predicted microRNAs (miRNAs) that targeted EGFR. Next, three NSCLC cell lines, A549 (p53 WT), H322 (p53 mutant), and H1299 (p53 null), were used to demonstrate the direct targeting of EGFR by miR-193a. In addition, we investigated the biological effects of EGFR inhibition by miR-193a in vitro using Cell Counting Kit-8, 5-Ethynyl-2'-deoxyuridine (EdU), transwell, and apoptosis assays. Then, using ChIP and luciferase assays, we demonstrated that miR-193a was directly activated by p53 at the transcriptional level and that p53-induced-miR-193a and EGFR form a double-negative feedback loop. RESULTS: We found that EGFR mRNA and protein were upregulated in NSCLC. We predicted that EGFR was a target of miR-193a and validated that miR-193a bound directly to the 3'-UTR of the EGFR mRNA. Moreover, miR-193a inhibited NSCLC proliferation and invasion, and promotes NSCLC apoptosis by directly downregulating EGFR. Then, we demonstrated that p53 directly activated miR-193a transcription, whereas EGFR functioned as a transcriptional repressor to negatively control miR-193a expression, forming a feedback loop. The loop promoted NSCLC cell proliferation and migration and accelerated tumor growth in xenograft mice. CONCLUSIONS: This study highlights a double-negative feedback loop in NSCLC. The feedback loop is crucial because overexpressing EGFR strongly accelerated tumor growth, while miR-193a restoration blocked tumor growth in vivo. Our findings are in line with the emerging opinion that miRNAs and protein regulators form regulatory networks in critical biological processes and that their dysregulation can lead to cellular dysfunction. In conclusion, this study provides important insights into the molecular mechanisms of NSCLC progression and may help inform the development of new therapeutics for managing NSCLC.

10.
Cancer Cell Int ; 19: 41, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30858758

RESUMO

BACKGROUND: Angiogenic factor with G-patch and FHA domain 1 (AGGF1), as a newly identified human angiogenic factor, is overexpressed in some types of malignant tumors and closely associated with patient's prognosis. However, the mechanisms involved in the regulation of AGGF1 in gastric cancer (GC) still remain unclear. METHODS: In this study, AGGF1 level in GC tissues and cell lines was analyzed by western blot and quantitative real-time polymerase chain reaction (qRT-PCR). After knockdown of AGGF expression by RNA interference in GC cell lines MKN-45 and MGC-803, wound healing and transwell assays were conducted to examine the effects of AGGF1 on migration and invasion. Tumor growth was assessed in a mouse xenograft model in vivo. Furthermore, expression levels of epithelial-mesenchymal transition (EMT) biomarkers and involvement of the Wnt/ß-catenin pathway were detected by western blot and qRT-PCR. RESULTS: Compared to those in normal groups, the protein and mRNA of AGGF1 expression levels were significantly higher both in GC tissues and cell lines (all P < 0.05). Knockdown of AGGF1 dramatically inhibited the invasion and migration of MKN-45 and MGC-803 cells (all P < 0.01) in vitro, and suppressed the tumor growth of nude mice xenograft model in vivo. Western blot revealed alterations in EMT biomarkers, suggesting the role of AGGF1 in EMT. Moreover, we found that downregulated expression of AGGF1 attenuated Wnt/ß-catenin related protein expression. CONCLUSIONS: Collectively, knockdown of AGGF1 inhibits the invasion and migration of gastric cancer via epithelial-mesenchymal transition through Wnt/ß-catenin pathway.

11.
Am J Cancer Res ; 6(8): 1681-94, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27648358

RESUMO

Drug resistance is one of the main hurdles for the successful treatment of hepatic carcinoma. However, the detailed mechanisms underlying resistance remain largely unknown and therapeutic approaches are limited. In the present study, we show that miR-122 confers resistance to 5-fluorouracil induced hepatocellular carcinoma cell apoptosis in vitro and reduces the potency of 5-fluorouracil in the inhibition of tumor growth in a mouse xenograft model in vivo. Further studies indicate that miR-122 modulates drug resistance through down-regulation of expression of PCDH20, which belongs to the protocadherin gene family and negatively regulates Akt activation. Knockdown of PCDH20 expression increases Akt phosphorylation, which leads to elevated mTOR activity and enhanced 5-fluorouracil resistance; whereas rescue of PCDH20 expression in miR-122-expressing cells decreases Akt and mTOR phosphorylation, re-sensitizing hepatocellular carcinoma cell to 5-fluorouracil induced apoptosis. Moreover, a specific and potent Akt inhibitor reverses miR-122-conferred 5-fluorouracil resistance. These findings indicate that the miR-122/PCDH20/Akt/mTOR signaling axis has an important role in mediating response to chemotherapy in human hepatocellular carcinoma. A major implication of our study is that inhibition of miR-122 or restoration of PCDH20 expression may have significant therapeutic potential to overcome drug resistance in hepatocellular carcinoma and that the combined use of an Akt inhibitor with 5-fluorouracil may increase efficacy in liver cancer treatment.

12.
Nanoscale ; 8(31): 14705-10, 2016 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-27443246

RESUMO

In this paper, porous flowerlike Pt-based (Pt, PdPt, RhPt and RhPdPt) nanocrystals were successfully achieved by a simple, economic, environmentally friendly route under the same synthetic conditions at 85 °C. The electrocatalytic properties of these flowerlike Pt-based nanocrystals toward alcohols (glycol, glycerol, methanol and ethanol) oxidation were investigated and they displayed enhanced catalytic performance compared with commercial Pt black. Among them, porous Pd45.5Pt54.5 nanoflowers showed the best catalytic performance with significant mass activity and long-term stability. More importantly, the current synthesis strategy can be easily amplified to gram-scale production.

13.
Med Oncol ; 32(4): 131, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25796501

RESUMO

Angiogenic factor with G-patch and FHA domains 1 (AGGF1) is a factor implicating in vascular differentiation and angiogenesis. Several lines of evidence indicate that aberrant expression of AGGF1 is associated with tumor initiation and progression. The aim of this study was to investigate the expression and prognostic value of AGGF1 in hepatocellular carcinoma (HCC), as well as its relationship with clinicopathological factors and tumor angiogenesis. Immunohistochemistry was performed to evaluate the expression of AGGF1 in HCC and paracarcinomatous tissues collected from 70 patients. Vascular endothelial growth factor (VEGF) and CD34 expression levels were examined in the 70 HCC tissues. Prognostic significance of tumoral AGGF1 expression was determined. Notably, AGGF1 expression was significantly higher in HCC than in surrounding non-tumor tissues (65.7 vs. 25.7 %; P < 0.001). AGGF1 expression was significantly correlated with tumoral VEGF expression and CD34-positive microvessel density. Moreover, AGGF1 expression was significantly associated with tumor size, tumor capsule, vascular invasion, Edmondson grade, alpha-fetoprotein level, and TNM stage. Kaplan-Meier survival analysis showed that high AGGF1 was correlated with reduced overall survival (OS) rate (P = 0.001) and disease-free survival (DFS) rate (P < 0.001). Multivariate analysis identified AGGF1 as an independent poor prognostic factor of OS and DFS in HCC patients (P = 0.043 and P = 0.010, respectively). Taken together, increased AGGF1 expression is associated with tumor angiogenesis and serves as an independent unfavorable prognostic factor for OS and DFS in HCC. AGGF1 may represent a potential therapeutic target for HCC.


Assuntos
Proteínas Angiogênicas/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/patologia , Neovascularização Patológica , Adulto , Idoso , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidade , Progressão da Doença , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Masculino , Microvasos/patologia , Pessoa de Meia-Idade , Análise Multivariada , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida
14.
Chem Asian J ; 10(3): 608-13, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25620545

RESUMO

Size-controllable, high-yield, island-shaped RhPdPt trimetallic nanocrystals with sub-2.0 nm islands have been successfully synthesized through a facile aqueous solution approach. The results of X-ray diffraction (XRD), energy-dispersive X-ray (EDX) line scanning and elemental mapping analysis showed the as-synthesized RhPdPt nanocrystals are alloy structures. These island-shaped RhPdPt trimetallic nanoalloys showed a composition-dependent electrocatalytic performance for ethanol oxidation in alkaline medium. Due to the special structure and intermetallic synergies, the Rh10Pd40Pt50 nanoalloys exhibited an enhanced catalytic activity and durability relative to island-shaped Pd50Pt50 bimetallic nanoalloys and commercial Pt black. The peak current density for Rh10Pd40Pt50 nanoalloys was 1.81 and 1.38 times that for commercial Pt black and Pd50Pt50 nanoalloys, respectively. In addition, the peak potential on Rh10Pd40Pt50 nanoalloys decreased 42 mV relative to commercial Pt black and Pd50Pt50 nanoalloys.

15.
Chem Commun (Camb) ; 50(88): 13551-4, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25244404

RESUMO

Composition-tunable PdPt bimetallic nanoalloys with sub-2.0 nm islands have been successfully synthesized through a facile aqueous solution approach. Among them, the Pd50Pt50 nanoalloys exhibit considerably higher catalytic activity and durability for methanol oxidation reaction than commercial Pt black.

16.
Langmuir ; 30(20): 5711-5, 2014 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-24821333

RESUMO

For the first time, composition-tunable, high-yield, RhPt flowerlike bimetallic nanocrystals were successfully synthesized through an aqueous solution approach. The electrocatalytic activity of these RhPt nanoalloys toward methanol oxidation was investigated and compared to the activity of commercial Pt black and commercial Ru50Pt50/C. The RhPt flowerlike bimetallic nanoallys have shown composition-dependent and superior catalytic properties relative to those of commercial Pt black and commercial Ru50Pt50/C. The peak current density and mass current value of Rh19Pt81 nanoalloys are 0.75 mA cm(-2) and 0.12 mA µg(-1), respectively. For commercial Pt black, they are 0.48 mA cm(-2) and 0.074 mA µg(-1), and for commercial Ru50Pt50/C, they are 0.28 mA cm(-2) and 0.10 mA µg(-1). Moreover, the chronoamperometric measurements show that the RhPt flowerlike nanoalloys have excellent stability over commercial Pt black and commercial Ru50Pt50/C.

17.
Med Oncol ; 30(1): 410, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23288726

RESUMO

Vascular endothelial growth factor (VEGF) is a major regulator of angiogenesis in the process of tumor growth and metastasis. Different VEGF gene polymorphisms have been shown to result in different VEGF protein expression in cancer cells and tumor angiogenic activity. We conducted a case-control study to evaluate the genetic effects of VEGF-460C/T polymorphism on the development of lung cancer. One hundred and twenty-six lung cancer patients and 160 sex-, age-, and ethnic-matched healthy controls were recruited for this study. The genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Odds ratios (ORs) and 95 % confidence intervals (CI) were calculated by logistic regression analysis. Our study showed that the TT genotype was associated with increased lung cancer risk than those with the CC (OR = 1.99, 95 % CI 1.05-3.77) or CT/CC (OR = 1.89, 95 % CI 1.17-3.06) genotype. Moreover, it was observed that the TT genotype associated with the advanced stage among lung cancer patients (TT vs. CC: OR = 3.09, 95 % CI 1.10-8.66). More studies are needed to detect VEGF-460C/T polymorphism and its association with lung cancer in different ethnic populations incorporated with environmental exposures.


Assuntos
Predisposição Genética para Doença/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Polimorfismo de Nucleotídeo Único , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Idoso , Povo Asiático/genética , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Polimorfismo de Fragmento de Restrição , Fatores de Risco , Adulto Jovem
18.
Med Oncol ; 28(2): 447-54, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20300977

RESUMO

Runx3 and CHFR genes were defined as tumor suppressor genes in gastric cancer (GC) recently. This paper was to investigate the roles of methylation and expression status of Runx3 and CHFR genes in GC patients. Methylation-specific polymerase chain reaction (MSP) and bisulfite DNA sequencing (BSP) were used to detect methylation status of Runx3 and CHFR genes in GC patients. The expression of Runx3 and CHFR in GC patients was analyzed by reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemical analysis. The expression of the protein and mRNA decreased remarkably in the patients with aberrant promoter methylation of Runx3 and CHFR genes. The methylation status of Runx3 and CHFR were inversely related to the tumor size, tumor invasion depth and tumor differentiation in GC patients. Moreover, the protein expression of Runx3 and CHFR were significantly correlated with tumor invasion depth and tumor differentiation, respectively. Aberrant promoter methylation of Runx3 and CHFR genes may be involved in the carcinogenesis and development of GC and may provide useful clues for the prediction of the malignant behaviors of GC.


Assuntos
Proteínas de Ciclo Celular/genética , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Metilação de DNA/genética , Proteínas de Neoplasias/genética , Neoplasias Gástricas/genética , Proteínas de Ciclo Celular/biossíntese , Subunidade alfa 3 de Fator de Ligação ao Core/biossíntese , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Estadiamento de Neoplasias , Proteínas de Ligação a Poli-ADP-Ribose , Regiões Promotoras Genéticas/genética , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Ubiquitina-Proteína Ligases
19.
Tumori ; 96(5): 726-33, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21302620

RESUMO

AIMS AND BACKGROUND: Transcriptional silencing induced by hypermethylation of CpG islands in the promoter regions of genes is believed to be an important mechanism of carcinogenesis in human cancers including gastric cancer. A number of reports on methylation of various genes in gastric cancer have been published, but most of these studies focused on cancer tissues or only a single gene. In this study, we determined the promoter hypermethylation status and mRNA expression of 4 genes: p16, Runx3, DAPK and CHFR. METHODS: Methylation-specific polymerase chain reaction (MSP) was used to determine the methylation status of p16, Runx3, DAPK and CHFR gene promoters in cancer and adjacent normal gastric mucosa specimens from 70 patients with gastric cancer, as well as normal gastric biopsy samples from 30 people without cancer serving as controls. In addition, the mRNA expression of p16, Runx3, DAPK and CHFR was investigated in 34 gastric cancer patients by RT-PCR. Bisulfite DNA sequence analysis was applied to check the positive samples detected by MSP. RESULTS: When carcinoma specimens were compared with adjacent normal gastric mucosa samples, a significant increase in promoter methylation of p16, Runx3, DAPK and CHFR was observed, while all 30 histologically normal gastric specimens were methylation free for all 4 genes. The methylation rate of the 4 genes increased from normal stomach tissue to tumor-adjacent gastric mucosa to gastric cancer tissue. Concurrent methylation in 2 or more genes was found in 22.9% of tumor-adjacent normal gastric mucosa and 75.7% of cancer tissues. No correlation was found between hypermethylation and other clinicopathological parameters such as sex, age, and tumor location. However, the frequency of DAPK and CHFR methylation in cancer tissues was significantly associated with the extent of differentiation and lymph node metastasis (P < 0.05) and the frequency of Runx3 methylation was significantly associated with tumor size (P < 0.05). Weak expression and loss of expression of the 4 genes was observed in cancer tissues and was significantly associated with promoter hypermethylation (P < 0.05). CONCLUSIONS: Promoter hypermethylation of p16, Runx3, DAPK and CHFR is frequent in gastric cancer. DAPK and CHFR promoter hypermethylation may be an important help in evaluating the differentiation grade and lymph node status of gastric cancer. Weak gene expression and loss of gene expression due to promoter hypermethylation may be a cancer-specific event.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Carcinoma/genética , Proteínas de Ciclo Celular/genética , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Metilação de DNA , Proteínas de Neoplasias/genética , Regiões Promotoras Genéticas/genética , Neoplasias Gástricas/genética , Adulto , Idoso , Carcinoma/patologia , Inibidor p16 de Quinase Dependente de Ciclina , Proteínas Quinases Associadas com Morte Celular , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Proteínas de Ligação a Poli-ADP-Ribose , RNA , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/patologia , Ubiquitina-Proteína Ligases
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