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1.
Nano Lett ; 24(17): 5324-5331, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38624236

RESUMO

Phase transformation offers an alternative strategy for the synthesis of nanomaterials with unconventional phases, allowing us to further explore their unique properties and promising applications. Herein, we first observed the amorphization of Pt nanoparticles on the RuO2 surface by in situ scanning transmission electron microscopy. Density functional theory calculations demonstrate the low energy barrier and thermodynamic driving force for Pt atoms transferring from the Pt cluster to the RuO2 surface to form amorphous Pt. Remarkably, the as-synthesized amorphous Pt/RuO2 exhibits 14.2 times enhanced mass activity compared to commercial RuO2 catalysts for the oxygen evolution reaction (OER). Water electrolyzer with amorphous Pt/RuO2 achieves 1.0 A cm-2 at 1.70 V and remains stable at 200 mA cm-2 for over 80 h. The amorphous Pt layer not only optimized the *O binding but also enhanced the antioxidation ability of amorphous Pt/RuO2, thereby boosting the activity and stability for the OER.

2.
Angew Chem Int Ed Engl ; 62(35): e202308800, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37428114

RESUMO

Water electrolysis for H2 production is restricted by the sluggish oxygen evolution reaction (OER). Using the thermodynamically more favorable hydrazine oxidation reaction (HzOR) to replace OER has attracted ever-growing attention. Herein, we report a twisted NiCoP nanowire array immobilized with Ru single atoms (Ru1 -NiCoP) as superior bifunctional electrocatalyst toward both HzOR and hydrogen evolution reaction (HER), realizing an ultralow working potential of -60 mV and overpotential of 32 mV for a current density of 10 mA cm-2 , respectively. Inspiringly, two-electrode electrolyzer based on overall hydrazine splitting (OHzS) demonstrates outstanding activity with a record-high current density of 522 mA cm-2 at cell voltage of 0.3 V. DFT calculations elucidate the cooperative Ni(Co)-Ru-P sites in Ru1 -NiCoP optimize H* adsorption, and enhance adsorption of *N2 H2 to significantly lower the energy barrier for hydrazine dehydrogenation. Moreover, a self-powered H2 production system utilizing OHzS device driven by direct hydrazine fuel cell (DHzFC) achieve a satisfactory rate of 24.0 mol h-1 m-2 .

3.
Angew Chem Int Ed Engl ; 60(12): 6533-6538, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33350566

RESUMO

Developing highly stable and efficient catalysts toward the oxygen reduction reaction is important for the long-term operation in proton exchange membrane fuel cells. Reported herein is a facile synthesis of two-dimensional coplanar Pt-carbon nanomeshes (NMs) that are composed of highly distorted Pt networks (neck width of 2.05±0.72 nm) and carbon. X-ray absorption fine structure spectroscopy demonstrated the metallic state of Pt in the coplanar Pt/C NMs. Fuel cell tests verified the excellent activity of the coplanar Pt/C NM catalyst with the peak power density of 1.21 W cm-2 and current density of 0.360 A cm-2 at 0.80 V in the H2 /O2 cell. Moreover, the coplanar Pt/C NM electrocatalysts showed superior stability against aggregation, with NM structures preserved intact for a long-term operation of over 30 000 cycles for electrode measurement, and the working voltage loss was negligible after 120 h in the H2 /O2 single cell operation. Density-functional theory analysis indicates the increased vacancy formation energy of Pt atoms for coplanar Pt/C NMs, restraining the tendency of Pt dissolution and aggregation.

4.
Chemistry ; 26(18): 4019-4024, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-31571290

RESUMO

Engineering noble metal nanostructures at the atomic level can significantly optimize their electrocatalytic performance and remarkably reduce their usage. We report the synthesis of atomically dispersed Pt on screw-like Pd/Au nanowires by using ultrafine Pd nanowires as seeds. Au can selectively grow on the surface of Pd nanowires by an island growth pattern to fabricate surface defect sites to load atomically dispersed Pt, which can be confirmed by X-ray absorption fine structure measurements and aberration corrected HRTEM images. The nanowires with 2.74 at % Pt exhibit superior HER properties in acidic solution with an overpotential of 20.6 mV at 10 mA cm-2 and enhanced alkaline ORR performance with a mass activity over 15 times greater than the commercial platinum/carbon (Pt/C) catalysts.

5.
Angew Chem Int Ed Engl ; 56(50): 16047-16051, 2017 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-29063649

RESUMO

Designing highly active catalysts at an atomic scale is required to drive the hydrogen evolution reaction (HER). Copper-platinum (Cu-Pt) dual sites were alloyed with palladium nanorings (Pd NRs) containing 1.5 atom % Pt, using atomically dispersed Cu on ultrathin Pd NRs as seeds. The ultrafine structure of atomically dispersed Cu-Pt dual sites was confirmed with X-ray absorption fine structure (XAFS) measurements. The Pd/Cu-Pt NRs exhibit excellent HER properties in acidic solution with an overpotential of only 22.8 mV at a current density of 10 mA cm-2 and a high mass current density of 3002 A g-1(Pd+Pt) at a -0.05 V potential.

6.
J Am Chem Soc ; 138(42): 13850-13853, 2016 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-27740759

RESUMO

We report a one-pot synthesis of atomically dispersed Ru on ultrathin Pd nanoribbons. By using synchrotron radiation photoemission spectroscopy (SRPES) and extended X-ray absorption fine structure (EXAFS) measurements in combination with aberration corrected high-resolution transmission electron microscopy (HRTEM), we show that atomically dispersed Ru with content up to 5.9% was on the surface of the ultrathin nanoribbon. Furthermore, the ultrathin Pd/Ru nanoribbons could remarkably prohibit the hydrogenolysis in chemoselective hydrogenation of C═C bonds, leading to an excellent catalytic selectivity compared with commercial Pd/C and Ru/C.

7.
Aging Male ; 18(1): 38-43, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24828371

RESUMO

OBJECTIVES: The metabolic syndrome (MetS) is proposed to predict future occurrence of cardiovascular diseases and diabetes. There are some other "non-traditional" risk factors such as hematogram components that are also related to the same endpoints as MetS. In this four-year longitudinal study, we used hematogram components to build models for predicting future occurrence of MetS in older men and women separately. METHODS: Subjects above 65 years without MetS and related diseases were enrolled. All subjects were followed up until they developed MetS or until up to four years from the day of entry, whichever was earlier. RESULTS: Among the 4539 study participants, 1327 developed MetS. Models were built for men and women separately and the areas under the receiver operation curves were significant. The Kaplan-Meier plot showed that the models could predict future MetS. Finally, Cox regression analysis showed that the hematogram model was correlated to future MetS with hazard ratios of 1.567 and 1.738 in men and women, respectively. CONCLUSION: Our hematogram models could significantly predict future MetS in elderly and might be more practical and convenient for daily clinical practice.


Assuntos
Contagem de Células Sanguíneas/métodos , Síndrome Metabólica/sangue , Síndrome Metabólica/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Estudos Longitudinais , Masculino , Fatores Sexuais
8.
Breast Cancer Res ; 16(5): 431, 2014 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-25228280

RESUMO

INTRODUCTION: Tamoxifen, a selective estrogen receptor (ER) modulator, may affect cancer cell survival through mechanisms other than ER antagonism. In the present study, we tested the efficacy of tamoxifen in a panel of ER-negative breast cancer cell lines and examined the drug mechanism. METHODS: In total, five ER-negative breast cancer cell lines (HCC-1937, MDA-MB-231, MDA-MB-468, MDA-MB-453 and SK-BR-3) were used for in vitro studies. Cellular apoptosis was examined by flow cytometry and Western blot analysis. Signal transduction pathways in cells were assessed by Western blot analysis. The in vivo efficacy of tamoxifen was tested in xenograft nude mice. RESULTS: Tamoxifen induced significant apoptosis in MDA-MB-231, MDA-MB-468, MDA-MB-453 and SK-BR-3 cells, but not in HCC-1937 cells. Tamoxifen-induced apoptosis was associated with inhibition of cancerous inhibitor of protein phosphatase 2A (CIP2A) and phospho-Akt (p-Akt) in a dose-dependent manner. Ectopic expression of either CIP2A or Akt protected MDA-MB-231 cells from tamoxifen-induced apoptosis. In addition, tamoxifen increased protein phosphatase 2A (PP2A) activity, and tamoxifen-induced apoptosis was attenuated by the PP2A antagonist okadaic acid in the sensitive cell lines, but not in resistant HCC-1937 cells. Moreover, silencing CIP2A by small interfering RNA sensitized HCC-1937 cells to tamoxifen-induced apoptosis. Furthermore, tamoxifen regulated CIP2A protein expression by downregulating CIP2A mRNA. Importantly, tamoxifen inhibited the in vivo growth of MDA-MB-468 xenograft tumors in association with CIP2A downregulation, whereas tamoxifen had no significant effect on CIP2A expression and anti-tumor growth in HCC-1937 tumors. CONCLUSIONS: Inhibition of CIP2A determines the effects of tamoxifen-induced apoptosis in ER-negative breast cancer cells. Our data suggest a novel "off-target" mechanism of tamoxifen and suggest that CIP2A/PP2A/p-Akt signaling may be a feasible anti-cancer pathway.


Assuntos
Antineoplásicos Hormonais/farmacologia , Apoptose/efeitos dos fármacos , Autoantígenos/metabolismo , Neoplasias da Mama/tratamento farmacológico , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Tamoxifeno/farmacologia , Idoso , Animais , Autoantígenos/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Estimativa de Kaplan-Meier , Masculino , Proteínas de Membrana/genética , Camundongos Nus , Pessoa de Meia-Idade , Receptores de Estrogênio/metabolismo , Transcrição Gênica , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Pharmacol Exp Ther ; 351(2): 352-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25187431

RESUMO

Some patients with nonsmall-cell lung cancer (NSCLC) without epidermal growth factor receptor (EGFR) mutations still respond to gefitinib and erlotinib, suggesting that there may be a mechanism(s) other than the EGFR pathway that mediates the tumoricidal effects. In the current study, we tested the efficacy of TD-19, a novel compound chemically modified from erlotinib, which has more potent apoptotic effects than erlotinib in EGFR wild-type NSCLC cell lines. TD-19 induced significant cell death and apoptosis in H358, H441, H460, and A549 cells, as evidenced by increased caspase-3 activity and cleavage of procaspase-9 and poly (ADP-ribose) polymerase. The apoptotic effect of TD-19 in H460 cells, which were resistant to erlotinib, was associated with downregulation of cancerous inhibitor of protein phosphatase 2A (CIP2A), increased protein phosphatase 2A (PP2A) activity, and decreased AKT phosphorylation, but minimal effects on EGFR phosphorylation. Overexpression of CIP2A partially protected the H460 cells from TD-19-induced apoptosis. Okadaic acid, a known PP2A inhibitor, significantly reduced TD-19-induced apoptosis, while forskolin, which increased PP2A activity, increased the apoptotic effect of TD-19. TD-19 inhibited the growth of H460 xenograft tumors by ∼80%. We conclude that TD-19 exerted tumoricidal effects on NSCLC cells. TD-19 provides proof that the CIP2A pathway may be a novel target for the treatment of EGFR wild-type NSCLC.


Assuntos
Apoptose/efeitos dos fármacos , Autoantígenos/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Receptores ErbB/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Proteínas de Membrana/metabolismo , Quinazolinas/farmacologia , Animais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Cloridrato de Erlotinib , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Nus , Fosforilação/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/metabolismo , Proteína Fosfatase 2/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
10.
Aging Male ; 17(4): 230-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24456526

RESUMO

BACKGROUND: The white blood cell (WBC) count was one of the first inflammatory markers associated with metabolic syndrome (MetS). Recently, two longitudinal studies have demonstrated a cause and effect relationship between MetS and WBC counts among middle-aged adults. However, no study has used WBC cutoff values to predict MetS in the elderly. METHODS: Subjects who underwent routine health checkups, and were above 60 years of age, were enrolled. All subjects were followed-up until they developed MetS or until 4 years from the date of entry, whichever came earlier. Of the 4539 subjects eligible for enrollment, 3428 subjects comprised the study group and 1111 subjects comprised the validation group. RESULTS: WBC counts were significantly different between subjects with and without MetS in both genders. Using the ROC curve, WBC cutoff values of 5.7 × 10(3)/µl in males and 5.0 × 10(3)/µl in females were associated with the increased risk of developing MetS (all p values <0.001). Using these WBC cutoff values, the hazard ratio (HR) for females was significant in both the study group and validation group. However, the HR for males failed significance in the validation group. Kaplan-Meier plots and κ coefficients confirmed that the WBC cutoff value could predict development of MetS in women but not in men. CONCLUSIONS: The association between WBC count and MetS was gender specific. A WBC cutoff value greater than 5.0 10(3)/µl may predict the development of MetS in elderly women.


Assuntos
Contagem de Leucócitos , Síndrome Metabólica/diagnóstico , Idoso , Feminino , Humanos , Estudos Longitudinais , Masculino , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais
11.
Jpn J Clin Oncol ; 43(3): 258-63, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23288931

RESUMO

OBJECTIVE: Most of the existing findings on the association between diabetes mellitus and colorectal cancer were generated from studies in Western societies. However, significant differences in cancer incidence and cancer-prone lifestyles are apparent between Asian and Western countries. This study aims to estimate the risks of colorectal cancer in the diabetic population in Taiwan by conducting a large-scale, controlled cohort study. METHODS: From Taiwan's Longitudinal Health Insurance Database 2005 (LHID2005), a total of 37 001 diabetic patients were identified. We also obtained data for four controls per patient, matched for sex, age and year of first entry into the LHID2005. All patients were followed up from the date of entry into the LHID2005 until they developed colorectal cancer or to the end of 2006, whichever was earlier. We used Cox's regression models to assess the risk of developing colorectal cancer, with adjustment for sex, age, comorbid disorders, and socioeconomic characteristics. RESULTS: We identified 37 001 diabetic patients and 148 004 controls. The adjusted hazard ratio for colorectal cancer in diabetes mellitus patients was 2.1 (95% confidence interval, 1.82-2.42) compared with controls. The risk was significant to both men and women. The adjusted hazard ratios for colorectal cancer were 2.03 (95% confidence interval, 1.68-2.47) in male diabetes mellitus patients and 2.17 (95% confidence interval, 1.77-2.67) in female diabetes mellitus patients. CONCLUSIONS: Our findings based on a large population-based cohort study provide evidence that diabetes mellitus may increase the risk of colorectal cancer in Asians.


Assuntos
Neoplasias Colorretais/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Bases de Dados Factuais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Vigilância da População , Risco , Distribuição por Sexo , Taiwan/epidemiologia , Adulto Jovem
12.
ACS Appl Mater Interfaces ; 11(45): 42298-42304, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31642318

RESUMO

We report an atomic-scale controllable synthesis of the face-centered cubic Ru overlayers on Pd nanosheets (Pd@Ru NSs) by a solution-based epitaxial growth method. The thickness of Ru overlayers can be accurately tuned at an atomic level, which has been confirmed by atomic force microscopy and high-angle annular dark-field scanning transmission electron microscopy. After annealing in air, the Pd@Ru NSs were transformed to PdO@RuO2 NSs with rutile RuO2 epitaxially grown on the PdO. The oxygen evolution reaction (OER) activity and stability strongly depend on the atomic layers of RuO2 and ∼4 atomic layers of RuO2 (PdO@RuO2-4layers) exhibit superior stability and optimal activity for OER with only 257 mV of the overpotential to reach 10 mA cm-2. Density functional theory calculations well reproduce the thickness dependence of OER activity and reveal that O* binds more weakly on the PdO@RuO2-4layers that boosts the rate-determining step for formation of HOO*, assuring the best OER performance.

13.
Oncotarget ; 9(5): 6402-6415, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29464081

RESUMO

PURPOSE: Impotence is one of the major complications occurring in prostate cancer patients after radical prostectomy (RP). Self-repair of the injured nerve has been observed in animal models and in patients after RP. However, the downstream signalling is not well documented. Here, we found that the DAPK/CIP2A complex is involved in GAS6/AXL-related Schwann cell proliferation. MATERIALS AND METHODS: The 3 groups were a sham group, a 14-day post-bilateral cavernous nerve injury (BCNI) group and a 28-day post-BCNI group. Erectile function was assessed and immunohistochemistry was performed. The rat Schwann cell RSC96 line was chosen for gene knockdown, cell viability, western blot, immunofluorescence and co-immunoprecipitation assays. RESULTS: The intracavernosal pressure was low on the 14th day after BCNI and partially increased by the 28th day. GAS6 and p-AXL expression gradually increased in the cavernous nerve after BCNI. RSC96 cells incubated with a GAS6 ligand showed increased levels of p-ERK1/2 and p-AKT. Moreover, DAPK and CIP2A.p-AXL and p-DAPK and CIP2A complexes were identified by both immunoblotting and co-immunoprecipitation. CONCLUSION: The DAPK/CIP2A complex is involved in GAS6/AXL-related Schwann cell proliferation. CIP2A inhibits PP2A activity, which results in p-DAPK(S308) maintenance and promotes Schwann cell proliferation. CIP2A is a potential target for the treatment of nerve injury after RP.

14.
ACS Appl Mater Interfaces ; 10(40): 34147-34152, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30211535

RESUMO

The activity and stability of bimetallic nanocatalysts strongly depend on their structures, compositions, and interfaces. Here, we report the synthesis of mesoporous Pd@Ru core-shell bimetallic nanorods composed of face-centered cubic Pd and hexagonal close-packed Ru. The nanorods have two types of cavities with diameters of 3.0 ± 0.9 and 20.3 ± 8.1 nm. The mutual diffusion process between Ru and Pd is characterized by the high-angle annular dark-field scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy mapping, and the synchrotron radiation photoemission spectroscopy measurements. The mesoporous Pd@Ru nanorods exhibit superior catalytic performance and stability for hydrogen evolution reactions (overpotentials of 30 mV at 10 mA·cm-2 in 1.0 M KOH solution and 37 mV at 10 mA·cm-2 in 0.5 M H2SO4 solution).

15.
Sci Rep ; 8(1): 929, 2018 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-29343793

RESUMO

The changes in neuronal nitric oxide synthases (nNOS) in the dorsal penile nerves (DPNs) are consistent with cavernous nerve (CN) injury in rat models. However, the anatomical relationship and morphological changes between the minor branches of the DPNs and the CNs after injury have never been clearly explored. There were forty 12 week old male Sprague-Dawley rats receiving bilateral cavernous nerve injury (BCNI). Erectile function of intracavernous pressure and mean arterial pressure were measured. The histology and ultrastructure with H&E stain, Masson's trichrome stain and immunohistochemical stains were applied on the examination of CNs and DPNs. We demonstrated communicating nerve branches between the DPNs and the CNs in rats. The greatest damage and lowest erectile function were seen in the 14th day and partially recovered in the 28th day after BCNI. The nNOS positive DPN minor branches' number was significantly correlated with erectile function. The sub-analysis of the number of nNOS positive DPN minor branches also matched with the time course of the erectile function after BCNI. We suggest the regeneration of the DPNs minor branches would ameliorate the erectile function in BCNI rats.


Assuntos
Disfunção Erétil/metabolismo , Disfunção Erétil/patologia , Óxido Nítrico Sintase Tipo I/metabolismo , Pênis/metabolismo , Pênis/patologia , Nervo Pudendo/metabolismo , Nervo Pudendo/patologia , Animais , Modelos Animais de Doenças , Masculino , Ereção Peniana/fisiologia , Ratos , Ratos Sprague-Dawley
16.
Nutrients ; 9(6)2017 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-28574481

RESUMO

The available findings concerning the association between branched-chain amino acids (BCAAs)-particularly leucine-and insulin resistance are conflicting. BCAAs have been proposed to elicit different or even opposite effects, depending on the prevalence of catabolic and anabolic states. We tested the hypothesis that leucine supplementation may exert different effects at different stages of insulin resistance, to provide mechanistic insights into the role of leucine in the progression of insulin resistance. Male Sprague-Dawley rats were fed a normal chow diet, high-fat diet (HFD), HFD supplemented with 1.5% leucine, or HFD with a 20% calorie restriction for 24 or 32 weeks. Leucine supplementation led to abnormal catabolism of BCAA and the incompletely oxidized lipid species that contributed to mitochondrial dysfunction in skeletal muscle in HFD-fed rats in the early stage of insulin resistance (24 weeks). However, leucine supplementation induced no remarkable alternations in BCAA catabolism, but did enhance mitochondrial biogenesis with a concomitant improvement in lipid oxidation and mitochondrial function during the hyperglycaemia stage (32 weeks). These findings suggest that leucine trigger different effects on metabolic signatures at different stages of insulin resistance, and the overall metabolic status of the organisms should be carefully considered to potentiate the benefits of leucine.


Assuntos
Aminoácidos de Cadeia Ramificada/metabolismo , Resistência à Insulina , Leucina/farmacologia , Mitocôndrias/efeitos dos fármacos , Aminoácidos de Cadeia Ramificada/sangue , Animais , Restrição Calórica , Dieta Hiperlipídica , Suplementos Nutricionais , Hiperglicemia/sangue , Hiperglicemia/tratamento farmacológico , Leucina/sangue , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Mitocôndrias/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Ratos , Ratos Sprague-Dawley
17.
Oncotarget ; 8(13): 20706-20718, 2017 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-28157701

RESUMO

Accumulating evidence is indicating metformin to possess the potential ability in preventing tumor development and suppressing cancer growth. However, the exact mechanism of its antitumorigenic effects is still not clear. We found that metformin suppressed the ability of cancer to skew macrophage toward M2 phenotype. Metformin treated cancer cells increased macrophage expression of M1-related cytokines IL-12 and TNF-α and attenuated M2-related cytokines IL-8, IL-10, and TGF-ß expression. Furthermore, metformin treated cancer cells displayed inhibited secretion of IL-4, IL-10 and IL-13; cytokines important for inducing M2 macrophages. Conversely, M1 inducing cytokine IFN-γ was upper-regulated in cancer cells. Additionally, through increasing AMPK and p65 phosphorylation, metformin treatment activated AMPK-NF-κB signaling of cancer cells that participate in regulating M1 and M2 inducing cytokines expression. Moreover, Compound C, an AMPK inhibitor, significantly increased IL-4, IL-10, and IL-13 expression while BAY-117082, an NF-κB inhibitor, decreased expression. In metformin-treated tumor tissue, the percentage of M2-like macrophages decreased while M1-like macrophages increased. These findings suggest that metformin activates cancer AMPK-NF-κB signaling, a pathway involved in regulating M1/M2 expression and inducing genes for macrophage polarization to anti-tumor phenotype.


Assuntos
Antineoplásicos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Metformina/farmacologia , Neoplasias Experimentais/imunologia , Proteínas Quinases Ativadas por AMP/imunologia , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Xenoenxertos , Humanos , Imuno-Histoquímica , Ativação de Macrófagos/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , NF-kappa B/imunologia , NF-kappa B/metabolismo , Neoplasias Experimentais/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos
18.
APMIS ; 124(12): 1031-1037, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27649840

RESUMO

Papillary thyroid carcinoma (PTC) is the most common type of thyroid carcinoma. CIP2A has recently been described as a prognostic marker in many cancers. In this study, we assessed the value of this novel prognostic marker in PTC. A total of 178 surgical specimens of both benign and malignant thyroid tumors were collected. Immunohistochemical staining for CIP2A, HBME-1, galectin-3, and CK19 was performed. Western blotting for CIP2A was also performed. CIP2A was expressed in 85.3% of malignant tumors and 12.1% of benign tumors. ROC analysis showed that the AUC for CIP2A was higher than those for other tumor markers. Western blotting showed that CIP2A expression was higher in PTC than in other tumors. Poor progression-free survival was observed in the high-CIP2A expression group. High CIP2A expression is a poor prognostic factor and can be a diagnostic marker in PTC. The presence of any two of the three indicated makers (CIP2A, galectin-3, and HBME-1) is strongly correlated with the diagnosis of PTC.


Assuntos
Autoantígenos/análise , Biomarcadores Tumorais/análise , Carcinoma/diagnóstico , Carcinoma/patologia , Proteínas de Membrana/análise , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/patologia , Adulto , Western Blotting , Carcinoma Papilar , Progressão da Doença , Feminino , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Estudos Retrospectivos , Análise de Sobrevida , Câncer Papilífero da Tireoide
19.
Nutr Res ; 36(8): 759-70, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27440530

RESUMO

The association between the age at introduction of complementary feeding and the risk of overweight or obesity during childhood has been hotly debated, but the result remains uncertain. This meta-analysis of prospective cohort studies attempted to evaluate this association, as well as provide evidence for infant feeding recommendations. The PubMed, Embase, and Cochrane databases were systematically searched for relevant original articles published prior to March 1, 2015 that met predefined inclusion criteria. The pooled relative risks (RRs) and corresponding 95% confidence intervals (CIs) were calculated using fix-effect or random-effect models, which were chosen based on heterogeneity among studies. Ten articles consisting of 13 studies, where 8 measured being overweight as an outcome and 5 measured being obese, were included in this meta-analysis. There were a total of 63,605 participants and 11,900 incident cases in the overweight studies, and 56,136 individuals and 3246 incident cases in the obese studies. The pooled results revealed that introducing complementary foods before 4months of age compared to at 4 to 6months was associated with an increased risk of being overweight (RR, 1.18; 95% CI, 1.06-1.31) or obese (RR, 1.33; 95% CI, 1.07-1.64) during childhood. No significant relationship was observed between delaying introduction of complementary foods after 6months of age, and being overweight (RR, 1.01; 95% CI, 0.90-1.13) or obese (RR, 1.02; 95% CI, 0.91-1.14) during childhood. The results of this study suggest that the introduction of complementary foods to infants before 4months of age should be avoided to protect against childhood obesity.


Assuntos
Fenômenos Fisiológicos da Nutrição do Lactente/fisiologia , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Fatores Etários , Índice de Massa Corporal , Estudos de Coortes , Humanos , Lactente , Estudos Prospectivos , Fatores de Risco
20.
Oncotarget ; 7(1): 638-55, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26575017

RESUMO

SET is known as a potent PP2A inhibitor, however, its oncogenic role including its tumorigenic potential and involvement in the development of chemoresistance in non-small cell lung cancer (NSCLC) has not yet been fully discussed. In present study, we investigated the oncogenic role of SET by SET-knockdown and showed that SET silencing impaired cell growth rate, colony formation and tumor sphere formation in A549 cells. Notably, silencing SET enhanced the pro-apoptotic effects of paclitaxel, while ectopic expression of SET diminished the sensitivity of NSCLC cells to paclitaxel. Since the SET protein was shown to affect chemosensitivity, we next examined whether combining a novel SET antagonist, EMQA, sensitized NSCLC cells to paclitaxel. Both the in vitro and in vivo experiments suggested that EMQA and paclitaxel combination treatment was synergistic. Importantly, we found that downregulating p-Akt by inhibiting SET-mediated protein phosphatase 2A (PP2A) inactivation determined the pro-apoptotic effects of EMQA and paclitaxel combination treatment. To dissect the critical site for EMQA functioning, we generated several truncated SET proteins. By analysis of the effects of EMQA on the binding affinities of different truncated SET proteins to PP2A-catalytic subunits, we revealed that the 227-277 amino-acid sequence is critical for EMQA-induced SET inhibition. Our findings demonstrate the critical role of SET in NSCLC, particularly in the development of chemoresistance. The synergistic effects of paclitaxel and the SET antagonist shown in current study encourage further validation of the clinical potential of this combination.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Chaperonas de Histonas/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Proteína Fosfatase 2/metabolismo , Fatores de Transcrição/metabolismo , Idoso , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proteínas de Ligação a DNA , Intervalo Livre de Doença , Sinergismo Farmacológico , Ativação Enzimática/efeitos dos fármacos , Feminino , Chaperonas de Histonas/antagonistas & inibidores , Chaperonas de Histonas/genética , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Paclitaxel/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinazolinas/administração & dosagem , Quinazolinas/farmacologia , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Ensaios Antitumorais Modelo de Xenoenxerto
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