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1.
Methods Mol Biol ; 2783: 93-107, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38478227

RESUMO

Murine models of obesity or reduced adiposity are a valuable resource for understanding the role of adipocyte dysfunction in metabolic disorders. Adipose tissue stromal vascular cells or primary adipocytes derived from murine adipose tissue and grown in culture are essential tools for studying the mechanisms underlying adipocyte development and function. Herein, we describe methods for the isolation, expansion, and long-term storage of murine adipose-derived stromal/stem cells, along with protocols for inducing adipogenesis to white or beige adipocytes in this cell population and osteogenic differentiation. Isolation of the adipose stromal vascular fraction cells for flow cytometric analysis is also described.


Assuntos
Adipogenia , Adiposidade , Camundongos , Humanos , Animais , Citometria de Fluxo/métodos , Osteogênese , Adipócitos , Tecido Adiposo , Diferenciação Celular , Obesidade/metabolismo , Células-Tronco
2.
PLoS One ; 17(3): e0265532, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35320304

RESUMO

To investigate the CGE on hair growth and to explore the mechanism that is involved in the acceleration of anagen induction, we investigated the effects of CGE studied on cell proliferation and molecular mechanism in human hair dermal papilla cells (hDPCs) and keratinocytes (HaCaT cells). Additionally, hair growth evaluation was carried out following topical treatment of the dorsal skin of telogen C57BL/6 mice with CGE for 14 days. As result, CGE increased cell viability and ALP activity in hDPCs. Moreover, CGE increased the expression of catenin beta 1 (CTNNB1), ALP, sex-determining region Y-box 2 (SOX2), insulin-like growth factor 1 (IGF1), and vascular endothelial growth factor A (VEGFA) genes in hDPCs. CGE increased the expression of proteins such as ALP, ß-catenin, and phosphorylation of glycogen synthase kinase 3ß (pGSK3ß), and protein kinase B (pAKT) in hDPCs. Furthermore, CGE induced the proliferation of HaCaT cells and up-regulated AKT-ERK-GSKß-ß-catenin signaling in HaCaT cells. Additionally, the anagen induction effects of CGE were confirmed on the telogen-anagen transition mice model. these findings demonstrated that CGE promoted the entering the growth phase of hair follicle via activation of ß-catenin signaling pathways in vivo. Thus, this study suggests that CGE might be a potential therapeutic reagent for hair growth.


Assuntos
Fator A de Crescimento do Endotélio Vascular , beta Catenina , Animais , Proliferação de Células , Células Cultivadas , Cabelo , Folículo Piloso/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
3.
Front Physiol ; 12: 780312, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34899399

RESUMO

Brown and beige adipocytes are specialized to dissipate energy as heat. Sgk2, encoding a serine/threonine kinase, has been identified as a brown and beige adipocyte-specific gene in rodents and humans; however, its function in brown/beige adipocytes remains unraveled. Here, we examined the regulation and role of Sgk2 in brown/beige adipose tissue thermogenesis. We found that transcriptional coactivators PGC-1α and NT-PGC-1α activated by the ß3 adrenergic receptor-cAMP-PKA pathway are recruited to the Sgk2 promoter, triggering Sgk2 transcription in response to cold. SGK2 elevation was closely associated with increased serine/threonine phosphorylation of proteins carrying the consensus RxRxxS/T phosphorylation site. However, despite cold-dependent activation of SGK2, mice lacking Sgk2 exhibited normal cold tolerance at 4°C. In addition, Sgk2+/+ and Sgk2-/- mice induced comparable increases in energy expenditure during pharmacological activation of brown and beige adipose tissue with a ß3AR agonist. In vitro loss- and gain-of-function studies further demonstrated that Sgk2 ablation or activation does not alter thermogenic gene expression and mitochondrial respiration in brown adipocytes. Collectively, our results reveal a new signaling component SGK2, although dispensable for cold-induced thermogenesis that adds an additional layer of complexity to the ß3AR signaling network in brown/beige adipose tissue.

4.
ACS Appl Mater Interfaces ; 13(45): 54124-54132, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34726365

RESUMO

High permittivity materials for a gigahertz (GHz) communication technology have been actively sought for some time. Unfortunately, in most materials, the dielectric constant starts to drop as frequencies increase through the megahertz (MHz) range. In this work, we report a large dielectric constant of ∼800 observed in defect-mediated rutile SnO2 ceramics, which is nearly frequency and temperature independent over the frequency range of 1 mHz to 35 GHz and temperature range of 50-450 K. Experimental and theoretical investigations demonstrate that the origin of the high dielectric constant can be attributed to the formation of locally well-defined Zn2+-Nb4+ defect clusters, which create hole-pinned defect dipoles. We believe that this work provides a promising strategy to advance dipole polarization theory and opens up a direction for the design and development of high frequency, broadband dielectric materials for use in future communication technology.

5.
BMC Genomics ; 22(1): 500, 2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34217204

RESUMO

BACKGROUND: Brown adipose tissue (BAT) is specialized to dissipate energy in the form of heat. BAT-mediated heat production in rodents and humans is critical for effective temperature adaptation of newborns to the extrauterine environment immediately after birth. However, very little is known about whether and how fetal BAT development is modulated in-utero in response to changes in maternal thermal environment during pregnancy. Using BL6 mice, we evaluated the impact of different maternal environmental temperatures (28 °C and 18 °C) on the transcriptome of the placenta and fetal BAT to test if maternal cold exposure influences fetal BAT development via placental remodeling. RESULTS: Maternal weight gain during pregnancy, the average number of fetuses per pregnancy, and placental weight did not differ between the groups at 28 °C and 18 °C. However, the average fetal weight at E18.5 was 6% lower in the 18 °C-group compared to the 28 °C-group. In fetal BATs, cold exposure during pregnancy induced increased expression of genes involved in de novo lipogenesis and lipid metabolism while decreasing the expression of genes associated with muscle cell differentiation, thus suggesting that maternal cold exposure may promote fetal brown adipogenesis by suppressing the myogenic lineage in bidirectional progenitors. In placental tissues, maternal cold exposure was associated with upregulation of genes involved in complement activation and downregulation of genes related to muscle contraction and actin-myosin filament sliding. These changes may coordinate placental adaptation to maternal cold exposure, potentially by protecting against cold stress-induced inflammatory damage and modulating the vascular and extravascular contractile system in the placenta. CONCLUSIONS: These findings provide evidence that environmental cold temperature sensed by the mother can modulate the transcriptome of placental and fetal BAT tissues. The ramifications of the observed gene expression changes warrant future investigation.


Assuntos
Tecido Adiposo Marrom , Temperatura Baixa , Animais , Feminino , Feto , Camundongos , Placenta , Gravidez , Termogênese , Transcriptoma
6.
J Radiat Res ; 62(2): 249-258, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33615367

RESUMO

Chemotherapy for cancer treatment has therapeutic limitations, such as drug resistance, excessive toxic effects and undesirable adverse effects. Therefore, efforts to improve the safety and efficacy of chemotherapeutic agents are essential. Ionizing radiation can improve physiological and pharmacological properties by transforming structural modifications of the drug. In this study, in order to reduce the adverse effects of rotenone and increase anticancer activity, a new radiolytic rotenone derivative called rotenoisin A was generated through radiolytic transformation. Our findings showed that rotenoisin A inhibited the proliferation of breast cancer cells and increased the rate of apoptosis, whereas it had no inhibitory effect on primary epidermal keratinocytes compared with rotenone. Moreover, rotenoisin A-induced DNA damage by increasing reactive oxygen species (ROS) accumulation. It was also confirmed not only to alter the composition ratio of mitochondrial proteins, but also to result in structural and functional changes. The anticancer effect and molecular signalling mechanisms of rotenoisin A were consistent with those of rotenone, as previously reported. Our study suggests that radiolytic transformation of highly toxic compounds may be an alternative strategy for maintaining anticancer effects and reducing the toxicity of the parent compound.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/patologia , Rotenona/farmacologia , Antineoplásicos/química , Neoplasias da Mama/metabolismo , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dano ao DNA , Feminino , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células MCF-7 , Proteínas Mitocondriais/metabolismo , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Rotenona/química , Proteína X Associada a bcl-2/metabolismo
7.
Sci Rep ; 11(1): 1323, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33446719

RESUMO

Transcriptional coactivator PGC-1α and its splice variant NT-PGC-1α regulate metabolic adaptation by modulating many gene programs. Selective ablation of PGC-1α attenuates diet-induced obesity through enhancing fatty acid oxidation and thermogenesis by upregulation of NT-PGC-1α in brown adipose tissue (BAT). Recently, we have shown that selective ablation of NT-PGC-1α reduces fatty acid oxidation in BAT. Thus, the objective of this study was to test our hypothesis that NT-PGC-1α-/- mice would be more prone to diet-induced obesity. Male and female NT-PGC-1α+/+ (WT) and NT-PGC-1α-/- mice were fed a regular chow or 60% high-fat (HF) diet for 16 weeks. Contrary to our expectations, both male and female NT-PGC-1α-/- mice fed HFD were protected from diet-induced obesity, with more pronounced effects in females. This lean phenotype was primarily driven by reduced dietary fat intake. Intriguingly, HFD-fed female, but not male, NT-PGC-1α-/- mice further exhibited decreased feed efficiency, which was closely associated with increased fecal fat excretion and decreased uptake of fatty acids by the intestinal enterocytes and adipocytes with a concomitant decrease in fatty acid transporter gene expression. Collectively, our results highlight the role for NT-PGC-1α in regulating whole body lipid homeostasis under HFD conditions.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Ingestão de Alimentos , Absorção Intestinal , Obesidade/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Animais , Fezes , Feminino , Masculino , Camundongos , Camundongos Knockout , Obesidade/induzido quimicamente , Obesidade/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
8.
Phys Rev Lett ; 125(18): 187203, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33196220

RESUMO

Recently, two-dimensional layered electrides have emerged as a new class of materials which possess anionic electrons in the interstitial spaces between cationic layers. Here, based on first-principles calculations, we discover a time-reversal-symmetry-breaking Weyl semimetal phase in a unique two-dimensional layered ferromagnetic (FM) electride Gd_{2}C. It is revealed that the crystal field mixes the interstitial electron states and Gd-5d orbitals near the Fermi energy to form band inversions. Meanwhile, the FM order induces two spinful Weyl nodal lines (WNLs), which are converted into multiple pairs of Weyl nodes through spin-orbit coupling. Further, we not only identify Fermi-arc surface states connecting the Weyl nodes but also predict a large intrinsic anomalous Hall conductivity due to the Berry curvature produced by the gapped WNLs. Our findings demonstrate the existence of Weyl fermions in the room-temperature FM electride Gd_{2}C, therefore offering a new platform to investigate the intriguing interplay between electride materials and magnetic Weyl physics.

9.
Nanomaterials (Basel) ; 10(7)2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32630839

RESUMO

We investigate the quantum confinement effects on excitons in several types of strain-free GaAs/Al 0 . 3 Ga 0 . 7 As droplet epitaxy (DE) quantum dots (QDs). By performing comparative analyses of energy-dispersive X-ray spectroscopy with the aid of a three-dimensional (3D) envelope-function model, we elucidate the individual quantum confinement characteristics of the QD band structures with respect to their composition profiles and the asymmetries of their geometrical shapes. By precisely controlling the exciton oscillator strength in strain-free QDs, we envisage the possibility of tailoring light-matter interactions to implement fully integrated quantum photonics based on QD single-photon sources (SPSs).

10.
Biomolecules ; 9(12)2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31817312

RESUMO

To determine the mechanism of action of the effects of phytoalexins in soybeans, we analyzed α-glucosidase inhibition kinetics using Michaelis-Menten plots and Lineweaver-Burk plots. The results showed that the type of inhibition with glyceollin was competitive, that of genistein was noncompetitive, that of daidzein was uncompetitive, and luteolin showed a mixed mode of action. The Ki values were determined using a Dixon plot as glyceollin, 18.99 µM; genistein, 15.42 µM; luteolin, 16.81 µM; and daidzein, 9.99 µM. Furthermore, potential synergistic effects between glyceollin and the three polyphenols were investigated. A combination of glyceollin and luteolin at a ratio of 3:7 exhibited synergistic effects on α-glucosidase inhibition, having a combination index (CI) of 0.64244, according to the CI-isobologram equation. Collectively, these results showed that a combination of glyceollin and luteolin has the potential to inhibit α-glucosidase activity via a synergistic mode of inhibition.


Assuntos
/enzimologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Sesquiterpenos/farmacologia , Sinergismo Farmacológico , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genisteína/farmacologia , Isoflavonas/farmacologia , Luteolina/farmacologia , Proteínas de Plantas/farmacologia , Pterocarpanos/farmacologia , alfa-Glucosidases/metabolismo , Fitoalexinas
11.
Phytomedicine ; 55: 172-178, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30668427

RESUMO

BACKGROUND: Centipedegrass extract (CGE) is rich in several polyphenolic compounds including C-glycosylflavonoids, such as maysin and its derivatives, and exerts antioxidant, anti-adipogenic and anticancer effects. However, the effect of CGE on the immune system is unclear. PURPOSE: CGE might inhibit NO production induced by lipopolysaccharide (LPS). In this study, we propose a molecular mechanism for regulation of aberrant immune responses by CGE in LPS-stimulated RAW264.7 cells. STUDY DESIGN: We will preparation of Centipedegrass extract and purify partially in rich of maysin and its derivatives. And examine the effect of the CGE on immune system using LPS-induced RAW cells and animals. METHODS: LPS-induced nitric oxide (NO) and interleukin-6 levels were measured by enzyme-linked immunosorbent assay. The mRNA and protein levels of immune mediators were analyzed by reverse-transcription polymerase chain reaction and immunoblotting, respectively. RESULTS: CGE inhibited LPS-induced NO production in a concentration-dependent manner by suppressing inducible nitric oxide synthase (iNOS) expression in LPS-stimulated cells; this effect was mediated by inhibition of the JAK/STAT pathway. However, CGE did not regulate the expression of other factors, including phosphorylated p38, c-jun N-terminal kinase, or extracellular signal-regulated kinase 1/2. In addition, CGE increased T cells percentage in peripheral blood after oral administration. CONCLUSION: These results indicate that CGE suppresses LPS-induced production of NO and expression of iNOS by directly inhibiting JAK2 kinase activity and enhancing effects on the immune system in mice.


Assuntos
Inibidores de Janus Quinases/farmacologia , Extratos Vegetais/imunologia , Extratos Vegetais/farmacologia , Poaceae/química , Administração Oral , Animais , Relação Dose-Resposta a Droga , Janus Quinase 2/metabolismo , Inibidores de Janus Quinases/imunologia , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Células RAW 264.7
12.
Oncol Rep ; 41(3): 1837-1850, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30569155

RESUMO

Kenalog is a synthetic glucocorticoid drug used to treat various cancers including ocular and choroidal melanoma. However, the drug achieves rarely sustainable results for patients. To overcome this difficulty, the structure of Kenalog was altered by ionizing radiation (IR) to develop a more effective anticancer agent for treatment of various skin cancers. The anticancer effect of modified Kenalog (Kenalog­IR) was assessed in melanoma cancer cells in vitro. The assessment of mitochondrial functions by MTT assay revealed significant inhibition of melanoma cancer cell viability by Kenalog­IR compared to Kenalog. Moreover, Kenalog­IR­induced apoptotic cell death was associated with the intrinsic mitochondrial pathway by triggering the release of intrinsic apoptosis molecules through activation of caspase­related molecules in concentration and time­dependent manners. Furthermore, it was observed that Kenalog­IR­induced apoptosis was associated with the generation of reactive oxygen species (ROS) with increased G2/M cell cycle arrest. Collectively, Kenalog­IR may be a potential suppressor of skin­related cancer in particular melanoma cancer.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Glucocorticoides/farmacologia , Radiação Ionizante , Triancinolona Acetonida/farmacologia , Antineoplásicos/química , Antineoplásicos/efeitos da radiação , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Pontos de Checagem da Fase G2 do Ciclo Celular , Glucocorticoides/química , Glucocorticoides/efeitos da radiação , Glucocorticoides/uso terapêutico , Humanos , Melanoma/tratamento farmacológico , Melanoma/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estrutura Molecular , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Triancinolona Acetonida/química , Triancinolona Acetonida/efeitos da radiação , Triancinolona Acetonida/uso terapêutico
13.
PLoS One ; 13(4): e0194341, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29617386

RESUMO

Dexamethasone (Dex) is widely used in the management of leukemia and lymphoma. While Dex is commonly used for hematological malignancies, the effects of Dex in solid cancer cells remain controversial. To develop a more effective anticancer drug for solid cancers, Dex was modified by ionizing radiation and the anticancer activity of ionizing-radiation-irradiated Dex (Dex-IR) was investigated in human lung cancer cells. Using the MTT assay, the proliferation of non-small cell lung cancer cells was significantly inhibited after treatment with Dex-IR compared with Dex. Furthermore, Dex-IR induced apoptotic cell death and cell cycle arrest of H1650 human lung cancer cells. The invasiveness of H1650 cells was significantly reduced and the matrix metalloproteinase activity was strongly suppressed. These results indicate that Dex-IR acts as a tumor suppressor by both inducing apoptosis and arresting the cell cycle. Although the structure of Dex-IR remains to be determined, our results suggest it may be useful as a novel anticancer agent for the treatment of solid cancers.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Dexametasona/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/efeitos da radiação , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dexametasona/farmacologia , Dexametasona/efeitos da radiação , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Metaloproteinases da Matriz/metabolismo , Invasividade Neoplásica
14.
J Anal Methods Chem ; 2018: 1651989, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29682395

RESUMO

Accumulation of ß-amyloid (Aß) plaques comprising Aß40 and Aß42 in the brain is the most significant factor in the pathogenesis of Alzheimer's disease (AD). Thus, the detection of Aß plaques has increasingly attracted interest in the context of AD diagnosis. In the present study, a fluorescent pyridazine-based dye that can detect and image Aß plaques was designed and synthesized, and its optical properties in the presence of Aß aggregates were evaluated. An approximately 34-fold increase in emission intensity was exhibited by the fluorescent probe after binding with Aß aggregates, for which it showed high affinity (KD = 0.35 µM). Moreover, the reasonable hydrophobic properties of the probe (log P = 2.94) allow it to penetrate the blood brain barrier (BBB). In addition, the pyridazine-based probe was used in the histological costaining of transgenic mouse (APP/PS1) brain sections to validate the selective binding of the probe to Aß plaques. The results suggest that the pyridazine-based compound has the potential to serve as a fluorescent probe for the diagnosis of AD.

15.
Surg Endosc ; 32(2): 760-769, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28791503

RESUMO

BACKGROUND: Surgical resection for esophagogastric junction (EGJ) tumors is more aggressive and worsens the quality of life of the patients and leads to poor prognosis even after surgery compared with tumors in other sites of the stomach. Endoscopic submucosal dissection (ESD) is a widely accepted treatment modality for premalignant lesions and early cancers in the stomach. However, EGJ tumor is one of the most technically difficult lesions to resect by ESD. Therefore, this study aimed to evaluate the therapeutic outcomes of ESD for EGJ epithelial neoplasms and to assess the predictive factors for incomplete resection. METHODS: We conducted a retrospective observational study of 48 patients who underwent ESD for adenomas and early cancers of the EGJ between March 2006 and November 2015 at the Pusan National University Hospital. Therapeutic outcomes of ESD and procedure-related adverse events were analyzed. RESULTS: En bloc resection, complete resection, and curative resection rates were 96, 77, and 71%, respectively. Multivariate analyses showed that the presence of ulceration was an independent predictive factor for incomplete resection (odds ratio 21.3, 95% confidence interval 1.51-298.49; p = 0.023). The procedure-related bleeding, perforation, and stenosis rates were 8, 4, and 0%, respectively; none of the adverse events required surgical intervention. During a median follow-up period of 25 months (range 6-72 months), local recurrence occurred in four patients with incomplete resection. CONCLUSION: ESD is an effective, safe, and feasible treatment for EGJ epithelial neoplasms. However, the complete resection rate decreases for tumors with ulceration.


Assuntos
Ressecção Endoscópica de Mucosa/métodos , Junção Esofagogástrica/cirurgia , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ressecção Endoscópica de Mucosa/efeitos adversos , Junção Esofagogástrica/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Resultado do Tratamento
16.
RSC Adv ; 8(18): 9895-9900, 2018 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35540802

RESUMO

Understanding the electronic band structure and density of states (DOS) of a material and their relationship to the associated electronic transport properties is the starting point for optimizing the performance of a device and its technological applications. In a hydrogenated Zn0.8Co0.2O (ZnCoO:H) film with an inverted thin-film transistor structure, we found ambipolar behavior, which is shown in many field-effect devices based on graphene, graphene nanoribbons, and organic semiconductors. In this study, to obtain information on the DOS of ZnCoO:H to explain the ambipolar behavior in terms of the carrier density and type, resistivity and magnetoresistance measurements of a ZnCoO:H film were performed at 5 K. Our proposed DOS representation of ZnCoO:H explains qualitatively the experimental observations of carrier density modulation and ambipolar behavior. First-principles calculations of the DOS of ZnCoO:H were in good agreement with the proposed DOS representation. Through a comparison of first-principles calculations and experimental data, evidence for the existence of Co-H-Co in ZnCoO:H is suggested.

17.
BMC Gastroenterol ; 17(1): 141, 2017 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-29207963

RESUMO

BACKGROUND: The prognosis of a gastrointestinal stromal tumor (GIST) is influenced by its anatomic site; however, few studies on the prognosis of gastric GISTs have been reported. The aims of this study were to evaluate long-term prognoses of patients who underwent surgical resection for gastric GISTs and to compare the clinical efficacy of two staging systems: the National Institutes of Health (NIH) consensus criteria and the 7th Union for International Cancer Control/American Joint Committee on Cancer (UICC/AJCC) tumor-node-metastasis (TNM) staging system. METHODS: We conducted a retrospective observational study of 145 patients who underwent surgical resection for gastric GISTs between February 2001 and June 2012 at Pusan National University Hospital (Busan, Korea). Recurrence and 5-year recurrence-free survival (RFS) rates were analyzed. RESULTS: During a median follow-up period of 44 months (range, 6-144 months), 11 recurrent lesions were detected in 9 patients (6.4%). On multivariate analysis, tumor size (>5 cm), mitotic count (>5/50 high-power fields), and epithelioid and mixed pathological type were significantly associated with recurrence. The overall 5-year RFS rate was 93.4%. Although no statistically significant differences were detected (C-statistic difference P = 0.886), all metrics showed lower values for the UICC/AJCC TNM staging system than for the NIH consensus criteria, suggesting that the UICC/AJCC TNM staging system may be a better model. CONCLUSIONS: The 5-year RFS rate in patients who underwent curative resection for gastric GISTs was excellent. The UICC/AJCC TNM staging system may be more useful than the NIH consensus criteria for risk categorization of patients with gastric GISTs.


Assuntos
Tumores do Estroma Gastrointestinal/patologia , Estadiamento de Neoplasias/métodos , Neoplasias Gástricas/patologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Seguimentos , Tumores do Estroma Gastrointestinal/mortalidade , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/cirurgia , Adulto Jovem
18.
Pharm Biol ; 55(1): 2110-2115, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28874080

RESUMO

CONTEXT: Aloe has been used for the prevention and cure of various diseases and symptoms including burns, injuries, oedema and pain. OBJECTIVE: This study determines the specific inhibitory activity of matrix metalloproteinase (MMP)-9 induced by the low molecular-weight gel fraction of Aloe vera (L.) Burm.f. (lgfAv) on alcohol-induced acute gastric lesions. MATERIALS AND METHODS: We examined the protective effects of oral (p.o.) administration of lgfAv (molecular weight cutoff <50.0 kDa, 150.0 mg/kg body weight) in a Balb/c mouse model of alcohol-induced acute gastritis for 1 h exposure. By measuring ulcer index, we compared the antiulcerative activity of the fraction. mRNA expression and immunohistochemical analysis of various biomarkers were performed. RESULTS: The lgfAv-treated mice exhibited drastically fewer ulcer lesions than the untreated control mice did. It featured that lgfAv lessened the ulcer lesions than their relevant controls. Moreover, the transcriptional level of MMP-9 was completely alleviated by lgfAv treatment in alcohol-treated gastritis-induced mice. DISCUSSION: The transcriptional level of MMP-9 was significantly alleviated by lgfAv treatment of the model. However, reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry experiments revealed that lgfAv treatment in mucosal tissues had the potential to inhibit the mRNA and protein expression levels of MMP-9, respectively. The protein expression of MMP-9 was closely associated with lgfAv-induced gastroprotection against alcohol-induced gastric lesions. CONCLUSIONS: The present findings suggest that lgfAv has the potential to alleviate alcohol-induced acute gastric lesions, which is mediated in part, mainly by the suppression of the mRNA expression of MMP-9.


Assuntos
Aloe , Etanol/toxicidade , Metaloproteinase 9 da Matriz/biossíntese , Extratos Vegetais/uso terapêutico , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/prevenção & controle , Animais , Indução Enzimática/efeitos dos fármacos , Indução Enzimática/fisiologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/enzimologia , Gastrite/induzido quimicamente , Gastrite/enzimologia , Gastrite/prevenção & controle , Géis , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Úlcera Gástrica/enzimologia
19.
Sci Rep ; 7(1): 11101, 2017 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-28894141

RESUMO

Magnetic oxide semiconductors with wide band gaps have promising spintronic applications, especially in the case of magneto-optic devices. Co-doped ZnO (ZnCoO) has been considered for these applications, but the origin of its ferromagnetism has been controversial for several decades and no substantial progress for a practical application has been made to date. In this paper, we present direct evidence of hydrogen-mediated ferromagnetism and spin polarization in the conduction band of ZnCoO. Electron density mapping reveals the formation of Co-H-Co, in agreement with theoretical predictions. Electron spin resonance measurement elucidates the ferromagnetic nature of ZnCoO by the formation of Co-H-Co. We provide evidence from magnetic circular dichroism measurements supporting the hypothesis that Co-H-Co contributes to the spin polarization of the conduction band of hydrogen-doped ZnCoO.

20.
Artigo em Inglês | MEDLINE | ID: mdl-28607575

RESUMO

Glucose deposition in peripheral tissue is an important parameter for the treatment of type 2 diabetes mellitus. The aim of this study was to investigate the effects of Spatholobus suberectus (Ss) on glucose disposal in skeletal muscle cells and additionally explore its in vivo antidiabetic potential. Treatment of ethanolic extract of S. suberectus (EeSs) significantly enhanced the glucose uptake, mediated through the enhanced expression of GLUT4 in skeletal muscle via the stimulation of AKT and AMPK pathways in C2C12 cells. Moreover, EeSs have potential inhibitory action on α-glucosidase activity and significantly lowered the postprandial blood glucose levels in STZ-induced diabetic mice, associated with increased expression of GLUT4 and AKT and/or AMPK-mediated signaling cascade in skeletal muscle. Furthermore, administration of EeSs significantly boosted up the antioxidant enzyme expression and also mitigated the gluconeogenesis enzyme such as PEPCK and G-6-Pase enzyme expression in liver tissue of STZ-induced diabetic mice model. Collectively, these findings suggest that EeSs have a high potentiality to mitigate diabetic symptoms through stimulating glucose uptake in peripheral tissue via the activation of AKT and AMPK signaling cascade and augmenting antioxidant potentiality as well as blocking the gluconeogenesis process in diabetic mice.

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