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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.
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.

6.
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).

7.
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.

8.
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
9.
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.

10.
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
11.
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
12.
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.

13.
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
14.
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
15.
Taiwan J Obstet Gynecol ; 55(1): 98-103, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26927258

RESUMO

OBJECTIVE: Cardiovascular events induced in breast cancer patients receiving radiotherapy (RT), chemotherapy (CT), or a combination of both (CRT) can increase the risk of death. This nationwide population-based study aims to estimate the risk of cardiovascular complications with a follow-up period of 5 years. MATERIALS AND METHODS: The study cohorts consisted of all patients hospitalized with a principal diagnosis of breast cancer who underwent treatment in 2002. The Cox proportional hazard model and Kaplan-Meier plot were analyzed to compare the cardiovascular event-free survival rate among breast cancer patients treated with different modalities. RESULTS: Of the 5514 breast cancer patients identified, 289 patients had cardiovascular disease (CVD): 110 (5.7%) from the surgery-alone group, 24 (4.1%) from the RT group, 79 (4.6) from the CT group, and 76 (5.8%) from the CRT group. Breast cancer patients who undergo CT and CRT at an age less than 55 years had a higher risk of CVD when compared with the surgery-alone group (for both groups, p < 0.001). By contrast, breast cancer patients aged over 55 years had no increased risk of CVD among the different treatment modalities. CONCLUSION: Breast cancer patients receiving CT and/or CRT have a higher risk of CVD, especially younger patients (aged < 55 years). Therefore, regular examinations of cardiac functions and electrocardiogram should be considered in cases of young breast cancer patients who are receiving CT and/or CRT.


Assuntos
Neoplasias da Mama/terapia , Doenças Cardiovasculares/epidemiologia , Mastectomia , Adulto , Fatores Etários , Idoso , Doenças Cardiovasculares/etiologia , Quimiorradioterapia Adjuvante , Quimioterapia Adjuvante , Estudos de Coortes , Feminino , Seguimentos , Humanos , Incidência , Pessoa de Meia-Idade , Radioterapia Adjuvante , Taiwan/epidemiologia
16.
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
17.
Biomed Res Int ; 2015: 359537, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26236724

RESUMO

Previously, we demonstrated that hypoxia (1% O2) enhances stemness markers and expands the cell numbers of cochlear stem/progenitor cells (SPCs). In this study, we further investigated the long-term effect of hypoxia on stemness and the bioenergetic status of cochlear spiral ganglion SPCs cultured at low oxygen tensions. Spiral ganglion SPCs were obtained from postnatal day 1 CBA/CaJ mouse pups. The measurement of oxygen consumption rate, extracellular acidification rate (ECAR), and intracellular adenosine triphosphate levels corresponding to 20% and 5% oxygen concentrations was determined using a Seahorse XF extracellular flux analyzer. After low oxygen tension cultivation for 21 days, the mean size of the hypoxia-expanded neurospheres was significantly increased at 5% O2; this correlated with high-level expression of hypoxia-inducible factor-1 alpha (Hif-1α), proliferating cell nuclear antigen (PCNA), cyclin D1, Abcg2, nestin, and Nanog proteins but downregulated expression of p27 compared to that in a normoxic condition. Low oxygen tension cultivation tended to increase the side population fraction, with a significant difference found at 5% O2 compared to that at 20% O2. In addition, hypoxia induced a metabolic energy shift of SPCs toward higher basal ECARs and higher maximum mitochondrial respiratory capacity but lower proton leak than under normoxia, where the SPC metabolism was switched toward glycolysis in long-term hypoxic cultivation.


Assuntos
Gânglio Espiral da Cóclea/citologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Animais , Biomarcadores/metabolismo , Western Blotting , Bromodesoxiuridina/metabolismo , Diferenciação Celular/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Respiração Celular/efeitos dos fármacos , Separação Celular , Células Cultivadas , Glicólise/efeitos dos fármacos , Imuno-Histoquímica , Camundongos Endogâmicos CBA , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Oxigênio/farmacologia , Células da Side Population/citologia , Esferoides Celulares/citologia , Esferoides Celulares/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
18.
Saudi J Gastroenterol ; 21(3): 158-64, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26021775

RESUMO

BACKGROUND/AIMS: Nonalchoholic fatty liver disease (NAFLD) has been reported as a hepatic manifestation of metabolic syndrome (MetS); it is common and accounts for 80% of the cases with abnormal liver function tests (LFTs). In addition, several studies have proved that there is a correlation between abnormal LFTs and MetS. Therefore, LFTs may represent the abnormal metabolic status of livers in the patients with MetS. To identify the early state of metabolic dysfunction, we investigate the value of LFTs for the future MetS development in the relatively healthy (non-NAFLD) elderly. PATIENTS AND METHODS: A total of 16,912 subjects met the criteria for analysis. In the first stage of this study, subjects were enrolled in the cross-sectional study in order to find out the optimal cutoff value in different LFTs with higher chances to have MetS. In the second stage of the present study, subjects with MetS at baseline were excluded from the same study group, and a median 5.6-year longitudinal study was conducted on the rest of the group. RESULTS: Among all LFTs, only aspartate aminotransferase in both genders and the α-fetal protein in women failed to show the significance in distinguishing subjects with MetS by the receiver operating characteristic curve. In the Kaplan-Meier plot, only γ-glutamyl transpeptidase (γ-GT) in men and the alanine aminotransferase (ALT) in women could be used to successfully separate subjects with higher risk of developing the MetS from those with lower risk. Finally, in the multivariant Cox regression model, similar results were identified. Still, the hazard ratio (HR) to have future MetS, γ-GT in men, and ALT in women showed significance (HR = 1.511 in men and 1.504 in women). CONCLUSION: Among all the different LFTs, γ-GT (>16 U/L) in male and ALT (>21 U/L) in female were the best predictors for the development of MetS in healthy elderly. These two liver markers could be an ancillary test in predicting future MetS development/diagnosis. Elevation of the LFTs without underlying liver diseases should be treated as a warning sign of the possible MetS development in the elderly.


Assuntos
Alanina Transaminase/metabolismo , Hepatite/enzimologia , Fígado/enzimologia , Síndrome Metabólica/enzimologia , Hepatopatia Gordurosa não Alcoólica/enzimologia , gama-Glutamiltransferase/metabolismo , Idoso , Aspartato Aminotransferases/metabolismo , Biomarcadores/metabolismo , Índice de Massa Corporal , Estudos de Coortes , Estudos Transversais , Feminino , Hepatite/fisiopatologia , Humanos , Fígado/diagnóstico por imagem , Fígado/fisiopatologia , Testes de Função Hepática , Estudos Longitudinais , Masculino , Síndrome Metabólica/fisiopatologia , Síndrome Metabólica/prevenção & controle , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Ultrassonografia , alfa-Fetoproteínas/metabolismo
19.
PLoS One ; 10(4): e0122675, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25875921

RESUMO

OBJECTIVE: This study investigated the trends in incidence and mortality of out-of-hospital cardiac arrest (OHCA), as well as factors associated with OHCA outcomes in Taiwan. METHODS: Our study included OHCA patients requiring cardiopulmonary resuscitation (CPR) upon arrival at the hospital. We used national time-series data on annual OHCA incidence rates and mortality rates from 2000 to 2012, and individual demographic and clinical data for all OHCA patients requiring mechanical ventilation (MV) care from March of 2010 to September of 2011. Analytic techniques included the time-series regression and the logistic regression. RESULTS: There were 117,787 OHCAs in total. The overall incidence rate during the 13 years was 51.1 per 100,000 persons, and the secular trend indicates a sharp increase in the early 2000s and a decrease afterwards. The trend in mortality was also curvilinear, revealing a substantial increase in the early 2000s, a subsequent steep decline and finally a modest increase. Both the 30-day and 180-day mortality rates had a long-term decreasing trend over the period (p<0.01). For both incidence and mortality rates, a significant second-order autoregressive effect emerged. Among OHCA patients with MV, 1-day, 30-day and 180-day mortality rates were 31.3%, 75.8%, and 86.0%, respectively. In this cohort, older age, the female gender, and a Charlson comorbidity index score ≥ 2 were associated with higher 180-day mortality; patients delivered to regional hospitals and those residing in non-metropolitan areas had higher death risk. CONCLUSIONS: Overall, both the 30-day and the 180-day mortality rates after OHCA had a long-term decreasing trend, while the 1-day mortality had no long-term decline. Among OHCA patients requiring MV, those delivered to regional hospitals and those residing in non-metropolitan areas tended to have higher mortality, suggesting a need for effort to further standardize and improve in-hospital care across hospitals and to advance pre-hospital care in non-metropolitan areas.


Assuntos
Comorbidade , Parada Cardíaca Extra-Hospitalar/mortalidade , Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Feminino , Hospitais , Humanos , Masculino , Parada Cardíaca Extra-Hospitalar/patologia , Caracteres Sexuais , Análise de Sobrevida , Taiwan
20.
Appl Immunohistochem Mol Morphol ; 23(3): 209-14, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25221955

RESUMO

BACKGROUND: The sensitivity in cytology diagnosis of malignant metastatic pleural effusion (MMPE) is insufficient nowadays due to the similarity of the reactive mesothelial cells and malignant cells. Vascular endothelial growth factor (VEGF) is one of the key factors in tumor lymphangiogenesis and metastasis. Therefore, the aim of this study was to evaluate the value of VEGF and its homologs in the aid of MMPE diagnosis. METHODS: A total of 217 pleural effusions samples were eligible for analysis. Among them, 81 malignant and 22 benign cases were made into the cell blocks for the immunocytochemical (ICC) staining of VEGF-A, VEGF-C, VEGF-D, VEGFR-2, and VEGFR-3 expression. Another 114 samples (41 malignant and 73 benign cases) were subjected to the ELISA test for the protein level of VEGF-D. RESULTS: In a total of 156 MMPE, only VEGF-D expression by ICC stain was significantly different between malignant (92.6%) and benign cases (9.1%) with P<0.001 in either nuclear or cytoplasmic staining. Only 6 malignant cases showed negative stain results. In addition, 3 of the 4 lung small cell carcinoma were immunoreactive for VEGF-D. However, some lymphocytes also showed nuclear staining pattern of VEGF-D. In contrast, the ELISA test for the VEGF-D protein levels failed to demonstrate the difference between malignant and benign pleural effusions. CONCLUSIONS: Among VEGF homologs, MMPE from various kinds of tumor origin, VEGF-D showed 92.6% rate of positive expression. ICC stain of VEGF-D is a useful marker in the aid of MMPE diagnosis.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Pequenas , Neoplasias Pulmonares , Proteínas de Neoplasias/metabolismo , Derrame Pleural Maligno , Fator D de Crescimento do Endotélio Vascular/metabolismo , Carcinoma de Células Pequenas/metabolismo , Carcinoma de Células Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Metástase Neoplásica , Derrame Pleural Maligno/metabolismo , Derrame Pleural Maligno/patologia , Estudos Retrospectivos
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