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1.
J Colloid Interface Sci ; 540: 285-294, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30660081

RESUMO

Highly porous (specific surface area, SBET, 1400 m2/g) and rich in surface groups activated carbons (ACs) were obtained from cotton stalks using either a direct or indirect activation. They were characterized by adsorption of nitrogen, thermal analysis combined with mass spectrometry, potentiometric titration, and X-ray photoelectron spectroscopy (XPS). XPS analysis indicated that the indirect activation led to more nitrogen on the surface incorporated as pyridinic and graphitic/quaternary species. These species were beneficial for a carbon application as oxygen reduction reaction (ORR) electrocatalysts and supercapacitors. The carbons were catalytically active in ORR with a number of electron transfer from 2.15 to 3.40 and onset potential of 0.810 V vs. reference hydrogen electrode (RHE). Their capacitance was around 180 F g-1 at 1 A g-1 when measured in an alkaline medium. The dependence of the performance on the porosity and nitrogen content was found, indicating suitability of cotton stalks obtained using the indirect activation as precursors of carbons of promising electrochemically active features.


Assuntos
Carvão Vegetal/química , Capacitância Elétrica , Gossypium/química , Nitrogênio/química , Adsorção , Catálise , Eletrodos , Hidrogênio/química , Oxirredução , Oxigênio/química , Porosidade
2.
Chin Med J (Engl) ; 131(2): 130-136, 2018 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-29336359

RESUMO

BACKGROUND: White matter lesions (WMLs) are common findings in brain magnetic resonance imaging (MRI) and are strongly associated with stroke incidence, recurrence, and prognosis. However, the relationship between WMLs and transient ischemic attacks (TIAs) is not well established. This study aimed to determine the clinical significance of WMLs in patients with TIA. METHODS: A total of 181 consecutive inpatients with first-ever TIA were enrolled. Brain MRIs within 2 days of symptom onset were used to measure WML volumes. Recurrent vascular events within 1 year of TIA onset were assessed. The relationship between WMLs and recurrent risk of vascular events was determined by a multivariate logistic regression. RESULTS: WMLs were identified in 104 patients (57.5%). Age and ratio of hypertension were significantly different between patients with and without WMLs. The incidence of vascular events in patients with WMLs significantly increased in comparison to those without WMLs (21.15% vs. 5.19%, 95% confidence interval [CI]: 1.18-15.20, P = 0.027) after controlling for confounders. Furthermore, distributions of WML loads were found to be different between patients who developed vascular events and those who did not. WML volumes were demonstrated to be correlated with recurrent risks, and the fourth quartile of WML volumes led to an 8.5-fold elevation of recurrent risk of vascular events compared with the first quartile (95% CI: 1.52-47.65, P = 0.015) after adjusting for hyperlipidemia. CONCLUSION: WMLs occur frequently in patients with TIA and are associated with the high risk of recurrent vascular events, suggesting a predictive neuroimaging marker for TIA outcomes.


Assuntos
Ataque Isquêmico Transitório/patologia , Substância Branca/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Ataque Isquêmico Transitório/diagnóstico por imagem , Modelos Logísticos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva , Substância Branca/diagnóstico por imagem
3.
Regul Toxicol Pharmacol ; 71(2): 285-94, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25592546

RESUMO

rAd5-hTERTC27, a replication-defective adenovirus vector carrying hTERTC27, has been proposed for possible use against hepatocellular carcinoma (HCC). In this study, we investigated the long-term toxicity of rAd5-hTERTC27 in SD rats and Cynomolgus monkeys. rAd5-hTERTC27 was administered intravenously once a week for 13 weeks followed by a one-month recovery period. As of 4 months, all animals displayed overall good health. Anti-adenoviral antibodies emerged in a dose-independent manner. The levels of complement components, C3 and C4, in the rAd5-hTERTC27 middle-dose and high-dose groups and C4 in the rAd5-EGFP group increased significantly after the 2nd treatment in monkeys. Slight-mild pathological changes of the liver occurred only in the rAd5-hTERTC27 high-dose group (2/16) in rats and not in any other group in either rats or monkeys. With the increase of the dose, the incidence of lymphocyte depletion in the spleen of rats and reactive hyperplasia of the splenic corpuscle in monkeys increased. However, the changes in the liver and spleen were reversible. Given the above data, intravenous administration of rAd5-hTERTC27 (up to 4×10(10)VP/kg in rats and 0.9×10(10)VP/kg in monkeys) appears to be well-tolerated, providing support for its potentially safe use in clinical trials for the treatment of HCC.


Assuntos
Adenoviridae , Vetores Genéticos/administração & dosagem , Vetores Genéticos/toxicidade , Telomerase/administração & dosagem , Telomerase/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Injeções Intravenosas , Neoplasias Hepáticas/tratamento farmacológico , Macaca fascicularis , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
4.
Mol Cancer ; 13: 191, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-25128329

RESUMO

BACKGROUND: The successful gene delivery into the brain is a major challenge due to the presence of the blood-brain barrier (BBB). In order to transport plasmid DNA across the BBB and target the brain glioma, the PEGylated liposomes (PLs) modified with OX26 and chlorotoxin (CTX) were developed as a dual-targeting gene delivery system, and the therapeutic efficacy of OX26/CTX-PL/pC27 against glioma was evaluated using in vitro and in vivo experimental models. METHODS: The PEGylated liposome complexes were prepared by the reverse phase evaporation method, and their physicochemical properties were examined. The transfection efficiency, intracellular distribution, in vitro effects of OX26/CTX-PL/pC27 were determined on C6, F98 and HEK293T cell lines. The dual-targeting therapeutic efficacy of OX26/CTX-PL/pC27 against glioma were assessed using the BMVECs/C6 cells co-culture model and the rat orthotopic glioma model. RESULTS: The OX26/CTX-PL/pDNA complexes exhibited a subglobose shape, and possessed notably low toxicities to HEK293T and C6 cells post 4 h incubation. In the in vitro transfection experiment, gene expressions of hTERTC27 from C6 and F98 cells were significantly improved by OX26 and CTX modification. Our in vitro results also showed that OX26 endowed the PLs with the transport ability across the BBB. Using the BMVECs/C6 cells co-culture model, the viability of C6 cells was decreased to 46.0% after OX26/CTX-PL/pC27 transfection. The OX26/CTX-PL/pC27 complexes exhibited enhanced therapeutic effects on C6 cells. Moreover, the dual-targeting therapeutic effects were further conformed with diminished tumor volumes (18.81 ± 6.15 mm³) and extended median survival time (46 days) in C6 glioma-bearing rats. Immunohistochemical analysis revealed the therapeutic effects derived from enhanced hTERTC27 expression in the tumor site. CONCLUSIONS: The PEGylated liposomes modified with OX26 and CTX are able to significantly promote cell transfection, increase the transport of plasmid DNA across the BBB and afterwards target the brain glioma cells in vitro and in vivo, exhibit the most significant therapeutic efficacy. The ligand OX26 plays a critical role in transporting the lipoplexes across the BBB, and CTX acts as a major role in targeting brain glioma cells. The results would encourage further developments for non-invasive targeting therapy of brain gliomas by intravenous injection.


Assuntos
Anticorpos Monoclonais Murinos/metabolismo , Neoplasias Encefálicas/metabolismo , Técnicas de Transferência de Genes , Glioma/metabolismo , Lipossomos/metabolismo , Venenos de Escorpião/metabolismo , Animais , Transporte Biológico , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Western Blotting , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Glioma/patologia , Células HEK293 , Humanos , Masculino , Tamanho da Partícula , Plasmídeos/metabolismo , Ratos Wistar , Eletricidade Estática , Transfecção
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