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1.
Macromol Rapid Commun ; 41(12): e2000144, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32400906

RESUMO

A new polymer acceptor poly{(N,N'-bis(2-ethylhexyl)-1,4,5,8-naphthalenedicarboximide-2,6-diyl)-alt-5,5-(3,3'-didodecyl-2,2'-bifuran)} (NDI-BFR) made from naphthalenediimide (NDI) and furan-derived head-to-head-linked 3,3'-dialkyl-2,2'-bifuran (BFR) units is reported in this study. Compared to the benchmark polymer poly(naphthalenediimide-alt-bithiophene) (N2200), NDI-BFR exhibits a larger bathochromic shift of absorption maxima (842 nm) with a much higher absorption coefficient (7.2 × 104 m-1 cm-1 ), leading to an ultranarrow optical bandgap of 1.26 eV. Such properties ensure good harvesting of solar light from visible to the near-infrared region in solar cells. Density functional theory calculation reveals that the polymer acceptor NDI-BFR possesses a higher degree of backbone planarity versus the polymer N2200. The polymer NDI-BFR exhibits a decent electron mobility of 0.45 cm2 V-1 s-1 in organic thin-film transistors (OTFTs), and NDI-BFR-based all-polymer solar cells (all-PSCs) achieve a power conversion efficiency (PCE) of 4.39% with a very small energy loss of 0.45 eV by using the environmentally friendly solvent 1,2,4-trimethylbenzene. These results demonstrate that incorporating head-to-head-linked BFR units in the polymer backbone can lead to increased planarity of the polymer backbone, reduced optical bandgap, and improved light absorbing. The study offers useful guidelines for constructing n-type polymers with narrow optical bandgaps.


Assuntos
Fontes de Energia Elétrica , Furanos/química , Imidas/química , Naftalenos/química , Polímeros/química , Energia Solar , Teoria da Densidade Funcional , Transistores Eletrônicos
2.
Med Sci Monit ; 24: 1097-1103, 2018 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-29467361

RESUMO

BACKGROUND Traumatic brain injury (TBI) is characterized by cognitive deficits, which was associated with brain oxidative stress and apoptosis. Resveratrol (RSV) is an anti-apoptotic and anti-oxidative. This study aimed to investigate neuroprotective effects and involved molecular mechanisms in TBI. MATERIAL AND METHODS RSV and p38 inhibitor were administrated to TBI rats. Cognitive deficits were evaluated by Morris water maze assay. Reactive oxygen species (ROS) and apoptosis were detected in rat brains by fluorescent staining. Western blotting was used to assess the phosphorylation of p38 and the expression levels of Nrf2, HO1, and activated caspase-3. RESULTS RSV administration attenuated cognitive deficits of TBI rats. The ROS generation and apoptosis in the brain of TBI rats were suppressed by RSV treatment. Moreover, RSV treatment recovered activation of p38/Nrf2/HO1 signaling pathway. The co-administration of p38 inhibitor impaired RSV's attenuating effects on cognitive deficits, brain apoptosis, and ROS generation. CONCLUSIONS RSV attenuated cognitive deficits of TBI by inhibiting oxidative stress-mediated apoptosis via targeting p38/Nrf2 signaling.


Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/metabolismo , Cognição/efeitos dos fármacos , Disfunção Cognitiva/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Antioxidantes , Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Lesões Encefálicas Traumáticas/enzimologia , Lesões Encefálicas Traumáticas/psicologia , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/enzimologia , Disfunção Cognitiva/patologia , Feminino , Masculino , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Resveratrol
3.
Neurocrit Care ; 26(2): 292-300, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27995513

RESUMO

OBJECTIVE: This study was to investigate the role of Nrf2/ARE signaling pathway in the pleiotropic neuroprotective effect of progesterone (PROG) on traumatic brain injury (TBI). METHODS: The Nrf2-knockout (Nrf2-/-) and C57 mice were respectively subjected to a lateral cortical impact injury caused by a free-falling object and randomly divided into three groups: sham-operated, trauma, and trauma + PROG treatment group. The PROG treatment group was given PROG (32 mg/kg of body weight, intraperitoneal injection) immediately after injury. For all groups, a series of brain samples were obtained after trauma at 24 and 72 h, respectively. The cerebral edema was evaluated; the expression of IL-1ß, IL-6, and TNF-α was measured using ELISA array, and the apoptosis index was detected by TUNEL. Flow cytometry was used to detect the intracellular calcium concentration. RESULTS: The water content, the apoptosis index, the levels of inflammatory cytokine, and the intracellular calcium ion were significantly decreased with the PROG treatment in C57 mice with TBI model. However, the effect of PROG on TBI was not found in the Nrf2-/- mouse model of TBI. CONCLUSIONS: PROG reduced cerebral edema, apoptosis, inflammatory reaction, and intracellular calcium ion overload effects after TBI. These beneficial effects were not seen in the Nrf2-/- mouse model of TBI. The results from this study suggested that the Nrf2/ARE signal pathway may be involved in the pleiotropic neuroprotective effect of PROG on TBI.


Assuntos
Elementos de Resposta Antioxidante/fisiologia , Lesões Encefálicas Traumáticas/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Progesterona/farmacologia , Transdução de Sinais/fisiologia , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Knockout , Fármacos Neuroprotetores/administração & dosagem , Progesterona/administração & dosagem
4.
Beilstein J Org Chem ; 12: 2443-2449, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28144311

RESUMO

We report a green and convenient protocol to prepare 4,7,12,15-tetrachloro[2.2]paracyclophane, the precursor of parylene D, from 2,5-dichloro-p-xylene. In the first bromination step, with H2O2-HBr as a bromide source, this procedure becomes organic-waste-free and organic-solvent-free and can appropriately replace the existing bromination methods. The Winberg elimination-dimerization step, using aqueous sodium hydroxide solution instead of silver oxide for anion exchange, results in a significant improvement in product yield. Furthermore, four substituted [2.2]paracyclophanes were also prepared in this convenient way.

5.
Acta Pharmacol Sin ; 34(12): 1485-90, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24241345

RESUMO

Traumatic brain injury is the leading cause of morbidity and mortality in young adults. The secondary injury in traumatic brain injury consists of a complex cascade of processes that simultaneously react to the primary injury to the brain. This cascade has been the target of numerous therapeutic agents investigated over the last 30 years, but no neuroprotective treatment option is currently available that improve neurological outcome after traumatic brain injury. Progesterone has long been considered merely a female reproductive hormone. Numerous studies, however, show that progesterone has substantial pleiotropic properties as a neuroprotective agent in both animal models and humans. Here, we review the increasing evidence that progesterone can act as a neuroprotective agent to treat traumatic brain injury and the mechanisms underlying these effects. Additionally, we discuss the current progress of clinical studies on the application of progesterone in the treatment of traumatic brain injuries.


Assuntos
Lesões Encefálicas/prevenção & controle , Fármacos Neuroprotetores/uso terapêutico , Progesterona/uso terapêutico , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Humanos
6.
Biomater Adv ; 149: 213390, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36963249

RESUMO

The development of fascinating materials with functional properties has revolutionized the humankind with materials comfort, stopped the spreading of diseases, relieving the environmental pollution pressure, economized government research funds, and prolonged their serving life. The outbreak of Coronavirus Disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has triggered great global public health concern. Face masks are crucial tools to impede the spreading of SARS-CoV-2 from human to human. However, current face masks exhibit in a variety of colors (opaque), like blue, black, red, etc., leading to a communication barrier between the doctor and the deaf-mute patient when wearing a mask. High optical transparency filters can be utilized for both personal protection and lip-reading. Thus, shaping face air filter into a transparent appearance is an urgent need. Electrospinning technology, as a mature technology, is commonly used to form nanofiber materials utilizing high electrical voltage. With the alteration of the diameters of nanofibers, and proper material selection, it would be possible to make the transparent face mask. In this article, the research progress in the transparent face air filter is reviewed with emphasis on three parts: mechanism of the electrospinning process and light transmission, preparation of transparent face air filter, and their innovative potential. Through the assessment of classic cases, the benefits and drawbacks of various preparation strategies and products are evaluated, to provide general knowledge for the needs of different application scenarios. In the end, the development directions of transparent face masks in protective gear, particularly their novel functional applications and potential contributions in the prevention and control of the epidemic are also proposed.


Assuntos
Filtros de Ar , COVID-19 , Nanofibras , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Filtração
7.
J Colloid Interface Sci ; 650(Pt B): 1446-1456, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37481782

RESUMO

The electrochemical CO2 reduction to specific multi-carbon product on copper-based catalysts is subjected to low activity and poor selectivity. Herein, catalyst structure, morphology, and chemical component are systematically studied for bolstering the activity and selectivity of as-prepared catalyzers in this study. Dendritic fibrous nano-silica spheres favor the loading of active species and the transport of reactant from the central radial channel. Cu/DFNS with high dispersion active sites are fabricated through urea-assisted precipitation way. The coexistence of Cu(I)/Cu(II) induces a close combination of Cu active sites and CO2 on the Cu/DFNS interface, promoting the CO2 activation and CC coupling. The Cu-O-Si interface (Cu phyllosilicate) can improve CO2 and CO attachment. Cu/DFNS show the utmost Faradaic efficiency of C2H4 with a value of 53.04% at -1.2 V vs. RHE. And more importantly, in-situ ATR-SEIRAS reveals that the CC coupling is boosted for effectively producing C2H4 as a consequence of the existence of *COL, *COOH, and *COH intermediates. The mechanism reaction path of Cu/DFNS is inferred to be *CO2 â†’ *COOH â†’ *CO â†’ *CO*COH â†’ C2H4. Our findings will be helpful to gain insight into the links between morphology, texture, chemical component of catalyzers, and electrochemical reduction of CO2, providing valuable guidance in the design of more efficient catalysts.

8.
Front Surg ; 9: 829048, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874127

RESUMO

Background: Primary brainstem lymphoma (PBSL) is rare and malignant. An understanding of this disease is lacking. We aimed to characterize clinical features, estimate survival, and explore survival-related factors of PBSL. Methods: Patients with a histological diagnosis of primary lymphoma in the brainstem (C71.7) from 1975 to 2016 were retrieved from the Surveillance, Epidemiology, and End Results (SEER) program. Log-rank tests and univariate and multivariate Cox proportional hazard analyses were used to identify survival-related factors. Results: PBSL constituted 2.7% of brainstem malignancies. The median age of the PBSL patients was 59.5 years. Diffuse large B cell lymphoma (n = 49, 84.5%) was the most prevalent histology among the 58 cases with reported specific lymphoma subtype. The majority of PBSLs were localized (n = 46, 52.3%), at low Ann Arbor Stage (I/II, n = 63, 70.5%), and presented as a single primary (n = 71, 80.7%). Chemotherapy was applied in 50 (56.8%) cases. Three-year overall survival (OS) and disease-specific survival (DSS) rates were 42.7% and 53.5%, respectively. Multivariate analyses showed that independent predictive/prognostic factors for OS were age (P = 0.004), tumor number (P = 0.029), and chemotherapy (P = 0.001); DSS-related factors only included age (P = 0.014) and chemotherapy (P = 0.008). Conclusions: We estimated survival rates for PBSL patients. Factors associated with OS and DSS were also identified. Our findings addressed the importance of chemotherapy in treating PBSL patients.

9.
J Colloid Interface Sci ; 619: 407-418, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35405573

RESUMO

Heterojunction engineering is a very prospective approach to modulate the photocatalytic behaviors of semiconductors. Herein, Venus flytrap-like NiCo hydroxide nanoflowers (HNF) with surface modification by different contents of CoSn(OH)6 were fabricated in situ for the first time. Interestingly, CoSn(OH)6 nanocubes (NC) are monodispersed on the nanosheet surface of NiCo HNF. Experimental characterizations and theoretical calculations comprehensively demonstrate the surface Sn atoms of CoSn(OH)6 are effectively embedded into the NiCo HNF interlayers, and co-sharing of the hydroxyl enables intimate contact in the heterointerface of NiCo HNF/CoSn(OH)6 hybrids and thereby largely shortens the charge migrating distance, contributing to an efficient interfacial charge migration and promoting charge separation. The optimized NiCo HNF/CoSn(OH)6 exhibits the remarkably enhanced photocatalytic efficiency for CO2 reduction with a TON of 601.2 and the CO and CH4 yield is about 3 folds that over CoSn(OH)6 NC. DRIFTS reveals the reaction intermediates in the CO2 photocatalytic process and proposes a possible mechanism for photocatalytic CO2 reaction. These findings may pave the way for rational engineering design of non-precious highly-dispersed broadband visible-light-driven CO2 reduction heterostructure catalysts.

10.
World J Clin Cases ; 10(1): 296-303, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35071531

RESUMO

BACKGROUND: Primary intracranial alveolar soft-part sarcoma (PIASPS) is a rare malignancy. We aimed to investigate the clinical profiles and outcomes for PIASPS. CASE SUMMARY: We firstly reported five consecutive cases from our institute. Then, the cases from previous studies were pooled and analyzed to delineate the characteristics of this disease. Our cohort included two males and three females. The median age was 21-years-old (range: 8-54-years-old). All the patients received surgical treatment. Gross total resection (GTR), radiotherapy, and chemotherapy were administered in 3 patients, 4 patients, and 1 patient, respectively. After a median follow-up of 36 mo, tumor progression was noticed in 4 patients; and 3 patients died of the disease. Pooled data (n = 14) contained 5 males and 9 females with a median age of 19 years. The log-rank tests showed that GTR (P = 0.011) could prolong progression-free survival, and radiotherapy (P < 0.001) resulted in longer overall survival. CONCLUSION: Patients with PIASPS suffer from poor outcomes. Surgical treatment is the first choice, and GTR should be achieved when the tumor is feasible. Patients with PIASPS benefit from radiotherapy, which should be considered as a part of treatment therapies.

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