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1.
Evol Psychol ; 19(1): 1474704920986866, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33487056

RESUMO

Cyclical fluctuations of the ovarian hormones estrogen (E2) and progesterone (PROG) have multiple effects on reproduction and development. However, little is known about the roles of E2 and PROG in women's social behaviors. Here, based on evolutionary theory suggesting social sensitivity and inhibition ability are conductive to maintaining social relationships, we provide evidence for the association between menstrual phases and social orientation. In Study 1, 78 women provided saliva samples and reported their intensity of behavioral activation/inhibition system (BAS/BIS) and interpersonal sensitivity at either of two phases of the menstrual cycle: late follicular phase (FP), and mid-luteal phase (LP). A significant between-subject association emerged, revealing that women with higher PROG levels reported higher levels of social feedback sensitivity, and women with relatively high PROG levels showed a positive association between their E2 levels and inhibitory response. In Study 2, 30 women reported their interpersonal anxiety and finished the social value orientation (SVO) measures at both late FP and mid-LP. A significant within-person effect emerged: women in the mid-LP, which is characterized by higher PROG levels, reported higher levels of interpersonal anxiety and SVO. In sum, these findings revealed that women's social orientation could fluctuate naturally with ovarian hormones across the menstrual cycle.

2.
Front Hum Neurosci ; 14: 568399, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33304251

RESUMO

Hormonal changes across the menstrual cycle have been shown to influence reward-related motivation and impulsive behaviors. Here, with the aim of examining the neural mechanisms underlying cognitive control of impulsivity, we compared event-related monetary delay discounting task behavior and concurrent functional magnetic resonance imaging (fMRI) revealed brain activity as well as resting state (rs)-fMRI activity, between women in the mid-luteal phase (LP) and women in the late follicular phase (FP). The behavioral data were analyzed and related to neural activation data. In the delay discounting task, women in the late FP were more responsive to short-term rewards (i.e., showed a greater discount rate) than women in the mid-LP, while also showing greater activity in the dorsal striatum (DS). Discount rate (transformed k) correlated with functional connectivity between the DS and dorsal lateral prefrontal cortex (dlPFC), consistent with previous findings indicating that DS-dlPFC circuitry may regulate impulsivity. Our rs-fMRI data further showed that the right dlPFC was significantly more active in the mid-LP than in late FP, and this effect was sensitive to absolute and relative estradiol levels during the mid-LP. DS-dlPFC functional connectivity magnitude correlated negatively with psychometric impulsivity scores during the late FP, consistent with our behavioral data and further indicating that relative estradiol levels may play an important role in augmenting cognitive control. These findings provide new insight into the treatment of conditions characterized by hyper-impulsivity, such as obsessive compulsive disorder, Parkinson disease, and attention deficit hyperactivity disorder. In conclusion, our results suggest that cyclical gonadal hormones affect cognitive control of impulsive behavior in a periodic manner, possibility via DS-dlPFC circuitry.

3.
World J Clin Cases ; 8(19): 4603-4608, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33083424

RESUMO

BACKGROUND: Hilar cholangiocarcinoma (CC) is a common malignant tumor with high malignancy and poor prognosis. Most patients have lost the opportunity to undergo radical surgery when diagnosed. Although palliative drainage or biliary stent placement is a preferable choice, the tumor cannot be controlled. This study aimed to develop a novel brachytherapy drainage tube for low-dose-rate brachytherapy with an effective drainage, thereby prolonging the survival time of patients. CASE SUMMARY: A 54-year-old male patient had undergone choledochal stent implantation due to obstructive jaundice. He was admitted to the hospital because of the recurrence of jaundice. Preoperative imaging and pathological biopsy revealed hilar CC (Bismuth-Corlette type IIIa). First, the patient underwent percutaneous transhepatic cholangial drainage and the symptoms of jaundice gradually relieved. To further treat hilar CC and remove the biliary drainage tube as far as possible, the patient chose to use the novel brachytherapy drainage tube after a multi-disciplinary consultation. After 1 mo of brachytherapy, the re-examination revealed that the obstructive lesions disappeared, and the drainage tube was finally removed. During the following 10 mo of follow-up, the patient's hilar CC did not recur. CONCLUSION: The novel brachytherapy drainage tube may be a new choice for patients with unresectable hilar CC.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32862342

RESUMO

Removing Co(II) from wastewater is urgent due to the threat to the environment and human health. In the work, the nanocomposite of graphene oxide-modified palygorskite (mPal-GO) is synthesized by cross-linking one-dimensional palygorskite (Pal) with two-dimensional material graphene oxide (GO), and used to remove Co(II) from wastewater. Its structure is characterized by Fourier transformed infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) surface area measurement. The parameters, such as mass ratio (GO:mPal), temperature, pH, and contact time, are carefully investigated. The results indicate that pseudo-second-order equation and Langmuir isotherm model are the best fitting one in the adsorption process of Co(II) onto mPal-GO. The maximum adsorption capacity achieves 16.9 mg/g at pH = 6.0 and T = 298 K according to the Langmuir model analysis. Furthermore, mPal-GO can be reused more than 5 times with a slight decrease according to the adsorption-desorption cycle experiments. Finally, mPal-GO with the low-cost and easy separation is a promising candidate for removing of Co(II) from wastewater.

5.
PLoS One ; 15(8): e0237032, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790683

RESUMO

The behavioral activation system (BAS) and the behavioral inhibition system (BIS) have been proposed to relate to stable traits that predict inter-individual differences in motivation. Prior reports point dopamine (DA) pathways, mainly including ventral tegmental area (VTA) and substantia nigra (SN), implicate in subserving reward-related functions associated with BAS and inhibitory functions related with BIS. However, as an important factor that affects DA releasing, it remains an open question whether the ovarian hormones may also be related to BIS/BAS. Here, to investigate effects of the estradiol (E2) and progesterone (PROG) on BIS/BAS and related DA pathways, we employed a BIS/BAS scale and the resting-state functional magnetic resonance imaging (fMRI) during the late follicular phase (FP) and the mid-luteal phase (LP). On the behavioral level, when women had high PROG levels, their E2 levels were found positively correlated with BIS scores, but those women whose PROG levels were low, their E2 levels were negative correlation with BIS scores. On the neural level, we demonstrated BAS was related with the VTA pathway, included brain reward regions of nucleus accumbens (NAc) and orbitofrontal cortex (OFC). Meanwhile, the BIS was correlated with the SN-dorsolateral prefrontal cortex (dlPFC) pathway. ROI-based resting-state functional connectivity (RSFC) analyses further revealed that, RSFC between the SN and dlPFC was modulated by ovarian hormones. With higher PROG levels, increased E2 levels among women were accompanied by stronger RSFC of the SN-dlPFC, but when PROG levels were low, E2 levels were negatively correlated with the SN-dlPFC RSFC. These findings revealed a combined enhancement effect of E2 and PROG on BIS, and the SN-dlPFC pathway was mainly involved in this process.


Assuntos
Encéfalo/fisiologia , Dopamina/fisiologia , Inibição Psicológica , Motivação/fisiologia , Ovário/fisiologia , Adulto , Afeto/fisiologia , Encéfalo/diagnóstico por imagem , Neurônios Dopaminérgicos/fisiologia , Estradiol/fisiologia , Feminino , Neuroimagem Funcional , Humanos , Imagem por Ressonância Magnética , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Progesterona/fisiologia , Psicofisiologia , Substância Negra/diagnóstico por imagem , Substância Negra/fisiologia , Área Tegmentar Ventral/diagnóstico por imagem , Área Tegmentar Ventral/fisiologia , Adulto Jovem
6.
ChemSusChem ; 13(14): 3543, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32627971

RESUMO

Invited for this month's cover is the research group of Rongzhi Chen at the University of Chinese Academy of Sciences and Xinming Wang at Guangzhou Institute of Geochemistry, Chinese Academy of Sciences. The image proposes an effective strategy to tune bonded oxygen species of carbon nitride for improving photocatalytic hydrogen production. The Full Paper itself is available at 10.1002/cssc.202001027.

7.
Neuroreport ; 31(10): 717-723, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32453019

RESUMO

The brain's default mode network (DMN) has become closely associated with self-referential mental activity, particularly in the resting-state. Prior reports point that the sex hormones are potent modulators of brain plasticity and functional connectivity. However, it is uncertain whether changes in ovarian hormones, as occur during the monthly menstrual cycle, substantially affects the functional connectivity of DMN. Here, we employed a Self-Awareness Scale (SAS) and the resting-state functional MRI in the late follicular phase and the mid-luteal phase to investigate the effect of the estradiol (E2) and progesterone on the SAS and DMN. On the behavioral level, increased progesterone facilitated women's other-focused attention. The regions of interest-based resting-state functional connectivity analyses continued to demonstrate a negative correlation of the relative progesterone and the medial prefrontal cortex-inferior temporal gyrus (mPFC-ITG) functional connectivity, and a facilitated effect of relative E2 on the mPFC-inferior parietal lobule functional connectivity in the DMN. Furthermore, as a core hub of the 'theory of mind', the functional connectivity between the ITG and thalamus was found negatively correlated with the relative E2. Meanwhile, the mid-luteal phase, which had significantly lower relative E2 levels, was indicated had stronger ITG-thalamus functional connectivity during the resting state. These results demonstrated an opposite effect of E2 and progesterone on the DMN and the other-focused preference in the mid-luteal phase, extended previous evidence of the potentially adaptive psychological effects of ovarian hormones on mapping self and others in the brain networks.

8.
ChemSusChem ; 13(14): 3605-3613, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32458562

RESUMO

Polymeric carbon nitrides (CNs) have been identified as attractive photocatalysts owing to their comparatively low cost and facile modification of their electronic structure. Herein, we report an effective strategy to tune the surface oxygen species linking site of polymeric CN, achieving more effective charge separation. A high photocatalytic hydrogen production rate of approximately 10225 µmol h-1 g-1 under visible light irradiation (λ>420 nm) and an impressive apparent quantum efficiency (AQE) of 5.7 % at 430 nm were recorded. Specifically, thermal treatment under a H2 and then an air atmosphere allowed the oxygen species linker on the surface of CN to be changed from -C=O to N=C-OH and then -C-O-C-, resulting in unbalanced charge distribution, which significantly enhanced the photogenerated charge separation, further contributing to the high hydrogen production performance. This linker regulation strategy may provide a new path for the development of highly efficient photocatalysts.

9.
Anal Chim Acta ; 1108: 61-69, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32222245

RESUMO

In this work, a multicolor visual immunoassay platform was developed. The photoelectric effects of Ag2S NPs@ZnO NTs made the color changes of PANI/PB, which enabled visual inspection of CEA. Under the visible light excitation, Ag2S NPs@ZnO NTs generates electron-holes. Where, photoelectrons will pass electrical circuit to PB and photoinduced holes will oxidize PANI, which making the PANI/PB composite changes from emerald green-blue-purple-black colors. When CEA was incubated, the migration rate of photogenerated carriers is slowed down owing to the steric hindrance, resulting in different color changes of PANI/PB. In addition, the average green channel of PANI/PB read by photoshop has a certain correlated linear relationship with the concentration of CEA. Meanwhile, we can observe the color transformation of PANI/PB with our own eyes. By integrating advantages of photoelectrochemistry and colorimetry, the linear range of CEA detection was 0.1-20 ng/mL, and the detection limit was 0.05 ng/mL (S/N = 3). More importantly, this multicolor sensing method is very convenient, simple and low-cost. The photocarriers-modulated colorimetric strategy also provides a novel idea for visual portable platform design in clinical diagnosis.

10.
Oncol Rep ; 43(2): 503-515, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31894340

RESUMO

Acute lymphoblastic leukemia (ALL) is a malignant hematological disease. Tanshinone IIA (Tan IIA) has antitumor activity in vitro and in vivo. The aim of the present study was to investigate the effects of Tan IIA in combination with imatinib (IM) on the proliferation, apoptosis, migration and invasion of acute T lymphocytic leukemia TIB­152 cells in vivo and in vitro, and analyze the potential underlying mechanism. Tan IIA and IM, alone and in combination, significantly inhibited proliferation, migration and invasion of TIB­152 cells, and promoted apoptosis; the effect of co­treatment with Tan IIA plus IM was enhanced. IGF­1 promoted the proliferation, migration and invasion of TIB­152 cells and inhibited apoptosis, while Tan IIA treatment significantly reversed these effects. In vivo experiments demonstrated that treatment with Tan IIA and IM, alone or in combination, significantly inhibited tumor growth in TIB­152 xenograft mice; the growth inhibition of Tan IIA plus IM was the strongest observed. Western blot analysis revealed that the combination of Tan IIA and IM resulted in significantly lower levels of p­PI3K, p­AKT and p­mTOR in cells and tissues compared with the IM and Tan alone treatment groups. In addition, the combination of Tan IIA and IM significantly decreased the levels of Ki67, cleaved caspase­3, VEGF and MMP­9 in cells and tissues, and the level of caspase­3 was significantly increased. Taken together, the results revealed that Tan IIA enhanced the inhibitory effect of imatinib on TIB­152 cell proliferation, migration and invasion, and induced apoptosis, which may be associated with inhibition of the PI3K/AKT/mTOR signaling pathway.


Assuntos
Abietanos/administração & dosagem , Antineoplásicos Fitogênicos/administração & dosagem , Mesilato de Imatinib/administração & dosagem , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Abietanos/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Mesilato de Imatinib/farmacologia , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Hazard Mater ; 384: 121252, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31581010

RESUMO

Nanoparticles film of copper metal hexacyanoferrates (CuHCF) was fabricated to electrochemically separate Co2+ in aqueous solutions under various conditions such as applied potential, solution pHs, initial concentrations, contact time and coexisting ions. Results showed that the removal efficiency conducted in reduction potential was obviously higher than that in oxidation potential. The optimal pH for Co2+ adsorption occurred at 8.0. Coexisting ions studies revealed that Co2+ could be removed from aqueous solutions containing Li+, Cu2+ and Al3+. Considering that cobalt and lithium are the main metallic elements in LiCoO2, the effect of different ionic strengths (IS) of LiNO3 (0.5, 1, 2, 5, 10) on adsorption was further investigated. Results showed that IS of LiNO3 had little impact on the removal efficiency of Co2+, which indicated the potential of selective recovery of cobalt from LiCoO2 in spent lithium-ion batteries. X-ray energy-dispersion spectroscopy (EDS) confirmed that the Co2+ could be adsorbed effectively onto CuHCF film. The adsorption was well described by Langmuir isotherm and the maximum sorption capacity is 218.82 mg/g. The kinetic rate of Co2+ adsorption was rapid initially and attained equilibrium within 60 min, and the data well fitted the Redlich-Peterson and the Elovich model, implying a chemisorption dominated process.

12.
Chem Commun (Camb) ; 55(96): 14478-14481, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31729499

RESUMO

In this work, a CoCu alloy magnetic unit was implanted in a photocatalytic system to improve photoinduced charge separation efficiency by regulating the electron transfer pathway via a giant magnetoresistance (GMR) effect, which achieved significantly enhanced hydrogen production activity driven by visible light. The amount of H2 produced in 3 h over the Pt@CoCu alloy decorated graphene (G) photocatalyst was about 12.2 times higher than that of Pt/G, and the highest apparent quantum efficiency (AQE) reached 34.4% at 520 nm.

13.
Radiat Prot Dosimetry ; 187(1): 88-97, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31135899

RESUMO

A comparison of Geant4 physics lists is conducted in the calculation of the total absorbed dose, boron dose, and non-boron dose in phantom, and the total depth-dose, boron depth-dose, and non-boron depth-dose along the beam axis for neutrons in a range of 0.0253 eV to 10 MeV. Physics processes are included for neutrons, photons, and charged particles, and calculations are conducted for neutrons and secondary particles. The results obtained from QBBC, QGSP_BERT, and neutron high precision physics lists with and without S(α, ß) data are compared with the FLUKA values. Neutron high precision physics lists with S(α, ß) data showed the best agreement with FLUKA in the studied energy range.


Assuntos
Terapia por Captura de Nêutron de Boro/métodos , Boro , Nêutrons , Imagens de Fantasmas , Fótons , Radiometria/métodos , Simulação por Computador , Humanos , Física , Dosagem Radioterapêutica
14.
J Appl Clin Med Phys ; 19(4): 313-318, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29808551

RESUMO

The purpose of this study was to obtain dosimetric parameters of GZP6 60 Co brachytherapy source number 3. The Geant4 MC code has been used to obtain the dose rate distribution following the American Association of Physicists in Medicine (AAPM) TG-43U1 dosimetric formalism. In the simulation, the source was centered in a 50 cm radius water phantom. The cylindrical ring voxels were 0.1 mm thick for r ≤ 1 cm, 0.5 mm for 1 cm < r ≤ 5 cm, and 1 mm for r > 5 cm. The kerma-dose approximation was performed for r > 0.75 cm to increase the simulation efficiency. Based on the numerical results, the dosimetric datasets were obtained. These results were compared with the available data of the similar 60 Co high dose rate sources and the detailed dosimetric characterization was discussed.


Assuntos
Braquiterapia , Anisotropia , Método de Monte Carlo , Imagens de Fantasmas , Radiometria , Dosagem Radioterapêutica
15.
Nat Commun ; 9(1): 1397, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29643347

RESUMO

Solar-driven water splitting using powdered catalysts is considered as the most economical means for hydrogen generation. However, four-electron-driven oxidation half-reaction showing slow kinetics, accompanying with insufficient light absorption and rapid carrier combination in photocatalysts leads to low solar-to-hydrogen energy conversion efficiency. Here, we report amorphous cobalt phosphide (Co-P)-supported black phosphorus nanosheets employed as photocatalysts can simultaneously address these issues. The nanosheets exhibit robust hydrogen evolution from pure water (pH = 6.8) without bias and hole scavengers, achieving an apparent quantum efficiency of 42.55% at 430 nm and energy conversion efficiency of over 5.4% at 353 K. This photocatalytic activity is attributed to extremely efficient utilization of solar energy (~75% of solar energy) by black phosphorus nanosheets and high-carrier separation efficiency by amorphous Co-P. The hybrid material design realizes efficient solar-to-chemical energy conversion in suspension, demonstrating the potential of black phosphorus-based materials as catalysts for solar hydrogen production.

16.
Proc Natl Acad Sci U S A ; 115(17): 4345-4350, 2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29563225

RESUMO

Few-layer black phosphorus (BP) nanosheets were first reported as a 2D material for the application of field-effect transistors in 2014 and have stimulated intense activity among physicists, chemists, and material and biomedical scientists, driving research into novel synthetic techniques to produce BP nanosheets. At present, exfoliation is the main route toward few-layer BP nanosheets via employing bulk BP as raw material. However, this is a complicated and time-consuming process, which is difficult for the large-scale synthesis of BP nanosheets. Moreover, BP degrades rapidly when exfoliated to nanoscale dimensions, resulting in the rapid loss of semiconducting properties. Here, we report the direct wet-chemical synthesis of few-layer BP nanosheets in gram-scale quantities in a bottom-up approach based on common laboratory reagents at low temperature, showing excellent stability due to partial oxidation of surface. Solvent and temperature are two critical factors, controlling not only the formation of BP nanosheets but also the thickness. The as-prepared BP nanosheets can extract hydrogen from pure water (pH = 6.8), exhibiting more than 24-fold higher activity than the well-known C3N4 nanosheets. Our results reporting the ability to prepare few-layer BP nanosheets with a facile, scalable, low-cost approach take us a step closer to real-world applications of phosphorene including next-generation metal-free photocatalysts for photosynthesis.

17.
Chem Commun (Camb) ; 54(15): 1845-1848, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29355862

RESUMO

We confirmed that Au nanoparticles (>10 nm) exhibit photocatalytic overall water splitting into H2 and O2 simultaneously with a ratio close to 2 : 1 without the assistance of sacrificial electron donors and cocatalysts under UV illumination for the first time. The hydrogen production rate of 5.7 µmol g-1 h-1 in pure water was achieved, which is higher than that of TiO2 nanoparticles (P25, 1.2 µmol g-1 h-1). The interband transitions from 5d (valence band) to 6sp (conduction band) are responsible for this photocatalytic activity over Au nanoparticles.

18.
Cell Stress Chaperones ; 23(4): 571-579, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29164525

RESUMO

Heat shock factor 4 controls the transcription of small heat shock proteins (e.g., HSP25, alpha B-cyrstallin, and r-crystallin), that play important roles in modulating lens proteostasis. However, the molecular mechanism underlying HSF4-mediated transcription is still unclear. Using yeast two hybrid, we found that HSF4 interacts with the ATP-dependent DEXD/H-box RNA helicase UAP56, and their interaction in lens epithelial cell line was further confirmed by GST-pull down assay. UAP56 is a vital regulator of pre-mRNA splicing and mature mRNA nuclear export. The immunofluorescence assay showed that HSF4 and UBA56 co-localize with each other in the nucleus of lens epithelial cells. Ectopic UAP56 upregulated HSF4-controlled HSP25 and alpha B-crystallin proteins expression, while knocking down UAP56 by shRNA reversed it. Moreover, UAP56 interacts with and facilitates the nuclear exportation of HSP25 and alpha B-crystallin mRNA without impacting their total mRNA expression level. In lens tissues, both UAP56 and HSF4 are expressed in the same nucleus of lens fiber cells, and their expression levels are simultaneously reduced with fiber cell maturation. Taken together, these data suggested that UAP56 is a novel regulator of HSF4 and might upregulate HSF4's downstream mRNA maturation and nuclear exportation.


Assuntos
RNA Helicases DEAD-box/metabolismo , Fatores de Transcrição de Choque Térmico/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Neoplasias/metabolismo , Cadeia B de alfa-Cristalina/metabolismo , Animais , Núcleo Celular/metabolismo , Células Epiteliais/metabolismo , Proteínas de Choque Térmico/genética , Humanos , Cristalino/citologia , Camundongos , Chaperonas Moleculares , Proteínas de Neoplasias/genética , Ligação Proteica
19.
Anal Biochem ; 531: 48-55, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28552756

RESUMO

In this work, three-dimensional (3D) hyperbranched TiO2 nanorod arrays were synthesized and used to fabricate dopamine sensitized photoelectrochemical (PEC) biosensor. To increase the lifetime of charge carriers and enhance the photocurrent responses signal, a delicate signal amplification strategy by introducing dopamine (DA) as sensitizer was developed. The dopamine sensitized TiO2 can shorten the carrier diffusion distance, improve light harvesting efficiency and charge collection efficiency, which results in performance improvement of the as-obtained PEC sensor. This proposed biosensor for determination of neuron specific enolase (NSE) demonstrated a good linear relationship range from 0.1 ng mL-1 to 1000 ng mL-1 with a detection limit of 0.05 ngmL-1 (S/N = 3). In addition, the as-prepared immunosensor exhibits excellent selectivity, stability and reproducibility, which could be extended to other label-free sensing fields. Therefore, this proposed method may also provide potential applications for the clinical examination.


Assuntos
Técnicas Biossensoriais/métodos , Dopamina/química , Fosfopiruvato Hidratase/análise , Titânio/química , Técnicas Biossensoriais/instrumentação , Humanos
20.
J Ethnopharmacol ; 191: 169-179, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27301615

RESUMO

ETHNOBOTANICAL RELEVANCE: Catalpol is the main active component of the radix from Rehmannia glutinosa Libosch, which has pleiotropic protective effects in neurodegenerative diseases, ischemic stroke, metabolic disorders and others AIM: Catalpol has been shown to have neuroprotective, neurorepair, and angiogenesis effects following ischemic brain injury. However, its molecular mechanisms are still poorly understood. In previous studies, the JAK2/STAT3 signaling pathway was found to play a role in neuroprotection and angiogenesis. This study investigated the role of catalpol in stimulating angiogenesis via the JAK2/STAT3 pathway after permanent focal cerebral ischemia (pMCAO). METHODS: Rats were subjected to right middle cerebral artery occlusion through electrocoagulation and were treated with catalpol (5mg/kg), AG490 was also used to inhibit STAT3 phosphorylation (pSTAT3). RESULTS: Following stroke, Catalpol improved the neuroethology deficit, increased the cerebral blood flow (CBF) of infarcted brain and upregulated EPO and EPOR. AG490 suppressed the phosphorylation of signal transducer and activator of transcription 3 (STAT3), ultimately inhibited VEGF mRNA expression, which reduced VEGF protein expression and inhibited stroke-induced angiogenesis. However, Catalpol enhanced stroke-induced STAT3 activation and subsequently restored STAT3 activity through the recovery of STAT3 binding to VEGF. Moreover, Catalpol reversed the effect of AG490 on STAT3 activation and nuclear translocation, restored the transcriptional activity of the VEGF promoter by recruiting STAT3 to the VEGF promoter, improved VEGF mRNA and protein expression, increased angiogenesis, reduced the difference in CBF between the infarcted and intact brain and ameliorated the neuroethology behaviors after stroke. CONCLUSION: Catalpol affects neuroprotection and angiogenesis via the JAK2/STAT3 signaling pathway, which is mediated by STAT3 activation and VEGF expression. Catalpol may be used as a potential therapeutic drug for stroke.


Assuntos
Indutores da Angiogênese/farmacologia , Encéfalo/efeitos dos fármacos , Artérias Cerebrais/efeitos dos fármacos , Infarto da Artéria Cerebral Média/tratamento farmacológico , Glucosídeos Iridoides/farmacologia , Janus Quinase 2/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fator de Transcrição STAT3/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Encéfalo/enzimologia , Encéfalo/patologia , Encéfalo/fisiopatologia , Artérias Cerebrais/enzimologia , Artérias Cerebrais/patologia , Artérias Cerebrais/fisiopatologia , Circulação Cerebrovascular/efeitos dos fármacos , Modelos Animais de Doenças , Eritropoetina/metabolismo , Infarto da Artéria Cerebral Média/enzimologia , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , Masculino , Fosforilação , Regiões Promotoras Genéticas , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Receptores da Eritropoetina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Ativação Transcricional , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/genética
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