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1.
Environ Technol ; 41(4): 420-429, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30015569

RESUMO

Most studies conducted nowadays to boost electrode performance in microbial fuel cell (MFC) have focused on carbonaceous materials. The titanium suboxides (Ti4O7, TS) are able to provide a new alternative for achieving better performance in MFC and have been tested and demonstrated in this study. The Ti4O7 electrode with high electrochemical activity was modified by graphene/polyaniline by the constant potential method. Electrogenic microorganisms were more conducive to adhere to the anode electrode due to the presence of graphene/polyaniline. The MFC reactor with polyaniline /graphene modified TS (TSGP) anode achieves the highest voltage with 980 mV, and produces a peak power density of 2073 mW/m2, which is 2.9 and 12.7 times of those with the carbon cloth anode, respectively, at the 1000â€…Ω external resistance. In addition, this study evaluates the effects of anolyte conductivity, pH, and COD on the treatment of oil-containing restaurant wastewater (OCRW) in MFC using TSGP anode. The OCRW amended with 120 mS/cm obtains the lowest internal resistance (160.3 Ω). Increasing the anodic pH, gradually from acidic (pH 5.5) to alkaline conditions (pH 8.0), resulted in a gradual increase in maximum power density to 576.4 mW/m2 and a decrease in internal cell resistance to 203.7 Ω. The MFC at the COD 1500 mg/L could obtain steady-state output voltage during 103 h while removing up to 65.2% of the COD of the OCRW.


Assuntos
Fontes de Energia Bioelétrica , Grafite , Compostos de Anilina , Eletricidade , Eletrodos , Restaurantes , Titânio , Águas Residuárias
2.
Nanoscale ; 10(40): 18942-18948, 2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30303226

RESUMO

A three-dimensional hierarchical Ni3Se2 nanorod array (NA) grown in situ on foam Ni is the first to act as a carbon/binder-free electrode of SIBs via a one-step reversible conversion reaction. By a special decomposition-fusion process, the morphology and composition of the NA are regulated to obtain ultrahigh areal capacity, which is three times greater than that reported for other metal selenides.

3.
Front Mol Neurosci ; 11: 129, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29740279

RESUMO

Organophosphate-induced delayed neuropathy (OPIDN) is characterized by progressive axonal degeneration and demyelination of the spinal cord and sciatic nerves. The neuregulin 1/epidermal growth factor receptor (ErbB) signaling pathway is crucial for axonal myelination. In this study, we investigated whether the neuregulin 1/ErbB signaling pathway mediated the progression of OPIDN. Adult hens were given tri-o-cresyl phosphate (TOCP), a typical neuropathic organophosphorus compound, to induce OPIDN. The ErbB inhibitor lapatinib was administered to hens 4 h prior to and 4 days after TOCP exposure. The neuregulin 1/ErbB signaling pathway was examined for their role in maintaining spinal cord and sciatic nerve fiber integrity. Schwann cell line sNF96.2 was used as the in vitro cell model. The in vivo results showed that TOCP (750 mg/kg body weight, p.o.) induced prominent ataxia and significant axon degeneration in the spinal cord and sciatic nerves. Lapatinib (25 mg/kg body weight, p.o.) treatment attenuated OPIDN clinically and histopathlogically and partially prevented the TOCP-induced activation of neuregulin 1/ErbB signaling pathway. Lapatinib also prevented the TOCP-induced inhibition of neuropathy target esterase (NTE), a key enzyme during the development of OPIDN, and the disturbed metabolism of phosphatidylcholine in sciatic nerves. In addition, lapatinib was shown, in vitro, to protect sNF96.2 cells from TOCP-induced dedifferentiation through neuregulin 1/ErbB signaling. Our results suggest that neuregulin 1/ErbB, through regulation of NTE activity in the peripheral nervous system, mediates the progression of OPIDN. Thus, this signal may serve as a potential target for the treatment of OPIDN.

4.
J BUON ; 22(2): 474-480, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28534372

RESUMO

PURPOSE: Gliomas are the most common primary intracranial tumors of the central nervous system (CNS), accounting for about one third of all brain tumors. Glioblastoma multiforme (GBM) is the aggressive grade IV glioma with survival as low as 2-5% in the second year post-diagnosis, hence necessitating efficient diagnostic markers. More than 50% of the non-small cell lung cancer (NSCLC) brain metastases are solitary lesions, often difficult to differentiate from gliomas by conventional imaging diagnostics. Here, we explored the utility of measuring serum expression levels of Micro-RNAs (miRs) 221, 608 and 504 as biomarkers for differentiating primary GBMs from solitary metastatic lesions of NSCLC. METHODS: Serum expression level of miRs 221, 608 and 504 were determined in 49 GBM, 27 NSCLC brain metastasis patients, and 30 cancer-free normal controls by real time PCR using commercially available miR specific primers. Mann-Whitney U test was used to compare the expression of each miR between each group. Receiver operating characteristics (ROC) curve analysis was also carried out to determine the feasibility of using miR expression as differential diagnosis test. RESULTS: Our results indicated that serum expression of mir-221 was upregulated in GBM as well as in metastatic NSCLC patients. Although both miR-608 and 504 were specifically downregulated only in the GBM patient group, ROC curve analysis showed that only miR-504 serum expression can be utilized as reliable differential diagnosis marker (sensitivity and specificity; 100 and 88.89% respectively). CONCLUSIONS: Serum expression level of miR-504 is a reliable biomarker to be used for differentiating primary GBM from solitary brain metastasis of NSCLC.


Assuntos
Neoplasias Encefálicas/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Glioblastoma/sangue , Neoplasias Pulmonares/sangue , MicroRNAs/sangue , Biomarcadores Tumorais/sangue , Encéfalo/patologia , Neoplasias Encefálicas/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Diagnóstico Diferencial , Regulação para Baixo/genética , Feminino , Glioblastoma/genética , Glioma/sangue , Glioma/genética , Humanos , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Regulação para Cima/genética
5.
Am J Transl Res ; 9(2): 802, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28337308

RESUMO

[This corrects the article on p. 3970 in vol. 8, PMID: 27725877.].

6.
J Neuropathol Exp Neurol ; 76(1): 52-60, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28040792

RESUMO

The widely used organophosphorus compound tri-o-cresyl phosphate (TOCP) elicits delayed neurotoxicity characterized by progressive axonal degeneration in the spinal cord and peripheral nerves. However, the precise mechanisms of TOCP-induced delayed neurotoxicity are not clear. Because autophagy has been linked to the pathogenesis of neurodegenerative diseases, we aimed to characterize autophagy in the progression of TOCP-induced delayed neurotoxicity. In vivo experiments using the adult hen animal model showed that autophagy in spinal cord axons and in sciatic nerves was markedly induced at the early preclinical stage of TOCP-induced delayed neurotoxicity; it was decreased as the delayed neurotoxicity progressed to the overt neuropathy stage. In cultured human neuroblastoma SH-SY5Y cells, TOCP reduced cell growth, and induced prominent autophagy. The autophagy inhibitor 3-methyladenine could attenuate TOCP-induced cytotoxicity, indicating that the autophagy is accountable for TOCP-induced neurotoxicity. In addition, we found that TOCP-induced Parkin translocation to mitochondria in SH-SY5Y cells, suggesting that autophagy may function to degrade mitochondria after TOCP exposure. These results suggest that autophagy may play an important role in the initiation and progression of axonal damage during TOCP-induced neurotoxicity.


Assuntos
Autofagia/efeitos dos fármacos , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Tritolil Fosfatos/toxicidade , Animais , Autofagia/fisiologia , Linhagem Celular Tumoral , Galinhas , Feminino , Humanos , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/metabolismo , Nervo Isquiático/patologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Medula Espinal/patologia
7.
Am J Transl Res ; 8(9): 3970-3975, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27725877

RESUMO

Glioblastoma is a highly malignant cancer of glioma cells. Present study investigates the anti proliferative activity of granatin B on glioma cell by inducing apoptosis. In this study Glioma cell (U87) was used on which anti proliferative activity of granatin B (0, 20, 40 & 80 µM) assessed by 3-(4, 5-dimethylthylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay. Thereafter Apoptosis of glioma cell was assessed by apoptosis detection kit suing flow cytometer, DAPI staining and by estimating the activity of caspase 3 & 9 using caspase 3 & 9 kit. Expression of MMP9 protein was determined through gelatin zymography. Possible mechanism of apoptosis induction was proved by estimating the effect of granatin B with MMP9 agonist on cell proliferation, caspase 3 activity & MMP9 expression on glioblastoma cell. Result of the study suggested that granatin B significantly decreases the cell proliferation of glioma cell compared to 0 µM treated group. It was also observed that treatment with granatin B significantly induces apoptosis and increases the activity of caspase 3 & 9 protein compared to 0 µM treated group. Expression of MMP9 protein was also decreases with granatin B treatment of glima cell. MMP9 agonist significantly reverses the effect of granatin B on cell proliferation, caspase 3 and expression of MMP9 protein in glima cell. Present study concludes the anticancer activity of granatin B on glioblastoma cell by inducing apoptosis.

8.
Chem Res Toxicol ; 28(6): 1216-23, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25856237

RESUMO

Cadmium (Cd) and chlorpyrifos (CPF) are widespread harmful environmental pollutants with neurotoxicity to mammals. Although the exposure to Cd and CPF at the same time may pose a significant risk to human health, the subchronic combined neurotoxicity of these two chemicals at low levels in the brain is poorly understood. In this study, we treated rats with three doses (low, middle, and high) of Cd, CPF, or their mixture for 90 days. No obvious symptom was observed in the treated animals except those treated with high-dose CPF. Histological results showed that middle and high doses of the chemicals caused neuronal cell damage in brains. GC-MS-based metabonomics analysis revealed that energy and amino acid metabolism were disturbed in the brains of rats exposed to the two chemicals and their combinations even at low doses. We further identified the unique brain metabolite biomarkers for rats treated with Cd, CPF, or both. Two amino acids, tyrosine and l-leucine, were identified as the biomarkers for Cd and CPF treatment, respectively. In addition, a set of five unique biomarkers (1,2-propanediol-1-phosphate, d-gluconic acid, 9H-purine, serine, and 2-ketoisovaleric acid) was identified for the mixtures of Cd and CPF. Therefore, the metabolomics analysis is more sensitive than regular clinical observation and pathological examination for detecting the neurotoxicity of the individual and combined Cd and CPF at low levels. Overall, these results identified the unique biomarkers for Cd and CPF exposure, which provide new insights into the mechanism of their joint toxicity.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cádmio/administração & dosagem , Cádmio/toxicidade , Clorpirifos/administração & dosagem , Clorpirifos/toxicidade , Metabolômica , Administração Oral , Animais , Biomarcadores/análise , Biomarcadores/metabolismo , Encéfalo/patologia , Relação Dose-Resposta a Droga , Leucina/análise , Leucina/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Tirosina/análise , Tirosina/metabolismo
9.
Nanoscale ; 7(3): 1073-80, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25475883

RESUMO

Localized surface plasmon (LSP) enhanced waveguide-type ultraviolet light-emitting diodes (LEDs) were fabricated by sputtering Ag nanoparticles (Ag-NPs) onto ZnO/MgZnO core/shell nanorod array (CS-NRA)/p-GaN heterostructures. A ∼9-fold enhancement of ZnO ultraviolet electroluminescence (EL) was demonstrated by the Ag-NPs decorated LED compared with the device without Ag-NPs. Angle-dependent EL measurements, as well as finite-difference time-domain simulations of the EL intensity spatial distribution, confirmed the waveguide-type EL transmission mode along the NR's axial direction. The increased spontaneous emission rate observed in time-resolved spectroscopy suggested that the ZnO EL enhancement was attributed to LSP-exciton/polariton coupling. However, a direct coupling is very difficult to achieve between Ag-LSPs and electron-hole pairs in the active region due to their "remote" separation. Thereby, two possible models involving the dynamic process of interactions among excitons, photons, and LSPs, were established to understand the selective enhancement of ZnO EL.

10.
J Zhejiang Univ Sci B ; 15(11): 979-85, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25367790

RESUMO

Salecan is a novel exopolysaccharide produced by the strain Agrobacterium sp. ZX09, and it is composed of only glucose monomers. The unique chemical composition and excellent physicochemical properties make Salecan a promising material for applications in coagulation, lubrication, protection against acute liver injury, and alleviating constipation. In this study, we cloned the Vitreoscilla hemoglobin gene into a broad-host-range plasmid pCM158. Without antibiotic selection, there was negligible loss of the plasmid in the host Agrobacterium sp. ZX09 after one passage of cultivation. The expression of Vitreoscilla hemoglobin was demonstrated by carbon monoxide (CO) difference spectrum. The engineered strain Agrobacterium sp. ZX09 increased Salecan yield by 30%. The other physiological changes included its elevated respiration rate and cellular invertase activity.


Assuntos
Agrobacterium/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Melhoramento Genético/métodos , Hemoglobinas Truncadas/genética , Hemoglobinas Truncadas/metabolismo , beta-Glucanas/metabolismo , Clonagem Molecular , Proteínas Recombinantes/metabolismo , beta-Glucanas/isolamento & purificação
11.
Nanoscale ; 5(18): 8634-9, 2013 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-23897294

RESUMO

Localized surface plasmon (LSP) enhanced ultraviolet (UV) light-emitting diodes (LEDs) were fabricated by embedding a ZnO nanorod array/p-GaN film heterostructure into a Ag-nanoparticles/PMMA composite. By optimizing the concentration of Ag nanoparticles in PMMA, two distinct changes in electroluminescence (EL) spectra were observed: (1) the UV EL component from ZnO excitons was selectively enhanced more than 13-fold and the entire spectral lineshape was changed and (2) the spatial uniformity of the output photon intensity was improved and the linewidth of an angular distribution curve was increased by ∼2 times. These observations can be attributed to near-field optical coupling between Ag LSPs and ZnO excitons. Time-resolved luminescence measurements and a model calculation reveal that the optical coupling results in the increase of the spontaneous emission rate and internal quantum efficiency of Ag-nanoparticles-decorated ZnO nanorod arrays. Moreover, the LSP-exciton interaction allows the device's EL to be coupled out of the nanorod waveguide and to be isotropically scattered into every direction, thus broadening the angular distribution of the EL intensity.

12.
J Int Med Res ; 41(3): 618-27, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23569028

RESUMO

OBJECTIVE: To investigate the effects of ischaemic postconditioning on brain injury and mitochondria in focal ischaemia and reperfusion, in rats. METHODS: Adult male Wistar rats (n = 15 per group) underwent sham surgery, ischaemia (2-h middle cerebral artery occlusion), or ischaemia followed by ischaemic postconditioning (three cycles of 30 s reperfusion/30 s reocclusion). Brain infarction size, neurological function, mitochondrial reactive oxygen species (ROS) production, mitochondrial membrane potential and mitochondrial swelling were evaluated 24 h postsurgery. RESULTS: Infarct size was significantly smaller, and neurological function was significantly better, in the ischaemic postconditioning group than in the ischaemia group. Ischaemia resulted in significant increases in mitochondrial ROS production and swelling, and a reduction in mitochondrial membrane potential, all of which were significantly reversed by postconditioning. CONCLUSIONS: The protective role of ischaemic postconditioning in focal ischaemia/reperfusion may be due to decreased mitochondrial ROS production, reduced mitochondrial membrane potential and suppressed mitochondria swelling. Mitochondria are potential targets for new therapies to prevent brain damage caused by ischaemia and reperfusion.


Assuntos
Isquemia Encefálica/metabolismo , Encéfalo/irrigação sanguínea , Pós-Condicionamento Isquêmico/métodos , Mitocôndrias/fisiologia , Traumatismo por Reperfusão/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Isquemia Encefálica/fisiopatologia , Infarto da Artéria Cerebral Média , Masculino , Potencial da Membrana Mitocondrial/fisiologia , Dilatação Mitocondrial/fisiologia , Atividade Motora/fisiologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/fisiopatologia
13.
Zhen Ci Yan Jiu ; 33(6): 372-6, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19288896

RESUMO

OBJECTIVE: To investigate the effects of electroacupuncture (EA) on the expression of corticotropin releasing hormone (CRH) and CRHR 1 mRNA in paraventricular nucleus (PVN) of hypothalamus, to explore its mechanism in anti-anxiety. METHODS: Thirty-three male SD rats were randomly divided into control, model and EA groups. Chronic emotional stress anxiety model was established by using chronic unpredictable emotional stress stimulation for 21 days. EA (15/25 Hz, 1-2 mA) was applied to "Baihui" (GV 20) and "Sanyinjiao" (SP 6) for 15 min/d and 21 days. The expression of CRH and CRHR 1 mRNA in hypothalamic PVN was measured by immunohistochemistry and in situ hybridization techniques separately. RESULTS: Compared with control group, the values of open-arms entries (OE%) and open-arms time (OT%) in model group were decreased significantly (P<0.01). In comparison with model group, OE% and OT% in EA group were increased obviously (P<0.05, P<0.01). Compared with control group, the optical density values of CRH immuno-reaction positive products and CRHR 1 mRNA expressed neurons of hypothalamic PVN in model group were increased obviously (P<0.05, P<0.01); while in comparison with model group, those of CRH and CRHR 1 mRNA in EA group were significantly decreased (P<0.05, P<0.01). CONCLUSION: EA can effectively relieve chronic stress stimulation induced anxiety in the rat, which is closely related to its effect in down regulating both CRH and CRHR 1 mRNA expression in PVN of hypothalamus.


Assuntos
Ansiedade/terapia , Hormônio Liberador da Corticotropina/genética , Eletroacupuntura , Expressão Gênica , Núcleos da Linha Média do Tálamo/fisiopatologia , Receptores de Hormônio Liberador da Corticotropina/genética , Animais , Ansiedade/genética , Ansiedade/metabolismo , Ansiedade/fisiopatologia , Hormônio Liberador da Corticotropina/metabolismo , Humanos , Masculino , Núcleos da Linha Média do Tálamo/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Estresse Fisiológico
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