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1.
Drug Deliv ; 26(1): 1191-1205, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31738085

RESUMO

Lycopene is considered as a promising neuroprotector with multiple bioactivities, while its therapeutic use in neurological disorders is restricted due to low solubility, instability and limited bioavailability. Our work aimed to develop lycopene-loaded microemulsion (LME) and investigate its potentials in improving bioavailability and brain-targeting efficiency following oral administration. The blank microemulsion (ME) excipients were selected based on orthogonal design and pseudo-ternary phase diagrams, and LME was prepared using the water titration method and characterized in terms of stability, droplet size distribution, zeta potential, shape and lycopene content. The optimized LME encompassed lycopene, (R)-(+)-limonene, Tween 80, Transcutol HP and water and lycopene content was 463.03 ± 8.96 µg/mL. This novel formulation displayed transparent appearance and satisfactory physical and chemical stabilities. It was spherical and uniform in morphology with an average droplet size of 12.61 ± 0.46 nm and a polydispersity index (PDI) of 0.086 ± 0.028. The pharmacokinetics and tissue distributions of optimized LME were evaluated in rats and mice, respectively. The pharmacokinetic study revealed a dramatic 2.10-fold enhancement of relative bioavailability with LME against the control lycopene dissolved in olive oil (LOO) dosage form in rats. Moreover, LME showed a preferential targeting distribution of lycopene toward brain in mice, with the value of drug targeting index (DTI) up to 3.45. In conclusion, the optimized LME system demonstrated excellent physicochemical properties, enhanced oral bioavailability and superior brain-targeting capability. These findings provide a basis for the applications of ME-based strategy in brain-targeted delivery via oral route, especially for poorly water-soluble drugs.

2.
J Integr Neurosci ; 18(3): 269-276, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31601075

RESUMO

Migraine is a primary neuropsychological disorder, although its etiology and pathogenesis are unknown. It has been reported that using contingent negative variation, the periodicity of migraine attacks is three days in adults. However, there is still a lack of relevant reports about the periodicity of migraine without aura in adults. Therefore, we investigated the changes of contingent negative variation in adults with migraine without aura from three to seven days after migraine attacks in order to provide the basis for exploring the circulation periodicity of migraine without aura. This prospective, observational study involved a group of 34 individuals with migraine without aura, who were screened during the three to seven days after a migraine attack without aura. A healthy group (31 individuals) was used as controls to assess the amplitudes of contingent negative variation and habituation of early contingent negative variation. Indices of the amplitudes included overall contingent negative variation, initial contingent negative variation, terminal contingent negative variation, and postoperative negative contingent variation. Differences between these indicators were analyzed. No significant difference was found between the patient and control groups for either the amplitudes of these measures of contingent negative variation or habituation of the early contingent negative variation for three to seven days after a migraine attack without aura (all P > 0.05). Thus, the study reported here found that the periodicity of migraine attacks without aura in adults is more than three days.

3.
Nat Commun ; 10(1): 3927, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477735

RESUMO

The duration of pregnancy is influenced by fetal and maternal genetic and non-genetic factors. Here we report a fetal genome-wide association meta-analysis of gestational duration, and early preterm, preterm, and postterm birth in 84,689 infants. One locus on chromosome 2q13 is associated with gestational duration; the association is replicated in 9,291 additional infants (combined P = 3.96 × 10-14). Analysis of 15,588 mother-child pairs shows that the association is driven by fetal rather than maternal genotype. Functional experiments show that the lead SNP, rs7594852, alters the binding of the HIC1 transcriptional repressor. Genes at the locus include several interleukin 1 family members with roles in pro-inflammatory pathways that are central to the process of parturition. Further understanding of the underlying mechanisms will be of great public health importance, since giving birth either before or after the window of term gestation is associated with increased morbidity and mortality.

4.
J Ethnopharmacol ; 241: 111956, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31129309

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Dryopteris fragrans (L.) Schott (D. fragrans), a deciduous perennial herb, has been traditionally used for treatment of various skin diseases in Heilongjiang province of China for many years. Phloroglucinol derivatives extracted from D. fragrans were the most effective fraction against dermatophytes. Isoflavaspidic acid PB is a typically phloroglucinol derivative which extracted from D. fragrans and has been reported to exert anti-fungal activities against several dermatophytes. AIM OF THE STUDY: This study aimed to evaluate anti-fungal and anti-biofilm activity of isoflavaspidic acid PB on planktonic and biofilm growth of dermatophytes and explore possible mechanisms of anti-biofilm. MATERIALS AND METHODS: Minimal inhibitory concentrations (MIC) and minimal fungicidal concentrations (MFC) of isoflavaspidic acid PB against 25 isolates of dermatophytes were determined by the Clinical and Laboratory Standards Institute (CLSI) M38-A2 method. The effects of isoflavaspidic acid PB on dermatophytes biofilm formation and pre-formed biofilm were assessed by 2.3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[carbonyl (phenylamino)]-2H-tetrazolium hydroxide (XTT) assay. Morphology of mature biofilm were observed by Scanning Electron Microscope (SEM). Biomass, exopolysaccharide and ergosterol content of mature biofilm were analyzed by gravimetric analysis, anthranone sulfuric acid method and Ultra Performance Liquid Chromatography (UPLC) assay respectively. RESULT: The MIC and MFC ranges of isoflavaspidic acid PB against 25 isolates of dermatophytes were 20-80 µg/mL and 40-80 µg/mL respectively. Isoflavaspidic acid PB (2 MIC) inhibited not only Trichophyton biofilm formation (54.8% ∼ 81.2%) but also the metabolic activity of mature biofilm (20.7% ∼ 44.2%). The result of SEM showed that isoflavaspidic acid PB (8 MIC) could destroy the morphology of hyphae seriously. Comparing with control group, biomass, exopolysaccharide and ergosterol content of the mature biofilm under isoflavaspidic acid PB (8 MIC) were significantly decreased (P < 0.01). CONCLUSION: Isoflavaspidic acid PB had anti-fungal and fungicidal activities against dermatophytes. Isoflavaspidic acid PB could inhibit the biofilm of Trichophyton. The mechanism might be related to the decline of the biofilm biomass, exopolysaccharide and ergosterol content. These results showed that isoflavaspidic acid PB could be explored for promising anti-biofilm drugs.

5.
J Headache Pain ; 20(1): 38, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31014235

RESUMO

BACKGROUND: Several studies have suggested cognitive deficits in migraineurs, and sex differences have also been observed in migraine, such as a higher prevalence in females. Nevertheless, little is known about gender-related differences in cognitive processing. In this study, we aimed to investigate the effect of gender on neurocognitive processing in migraineurs. METHODS: Altogether, 46 migraine patients without aura (23 females; mean age 32.848 years) during the interictal period and 46 age-matched healthy controls (23 females; mean age 32.652 years) were recruited. The emotional characteristics of participants were evaluated, and attentive processing was analyzed via event-related potential examinations using a three-stimulus visual oddball paradigm. RESULTS: We found that migraineurs suffered from emotional and visual cognitive processing abnormalities compared with healthy controls, including higher levels of anxiety and reduced P3 amplitude. These parameters were modulated by gender in migraine patients, but not in healthy participants. Our findings indicated that female patients seemed to be more anxious and have more severe impairment in attentive processing of visual stimuli than their male counterparts. The gender-related differences in migraineurs were further validated using event-related potential difference waveforms. CONCLUSIONS: These results suggested that migraine might have an additional influence on females and lead to more dysfunction in their interictal neurocognitive processing. Our findings provide evidence that a gender effect exists in migraineurs, which should be considered when designing experiments and exploring treatment approaches. The gender-related differences and underlying mechanisms deserve further investigation for patients with migraine.


Assuntos
Cognição/fisiologia , Potenciais Evocados Visuais/fisiologia , Transtornos de Enxaqueca/diagnóstico , Transtornos de Enxaqueca/fisiopatologia , Caracteres Sexuais , Adulto , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/psicologia
6.
BMC Neurol ; 19(1): 73, 2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-31029122

RESUMO

BACKGROUND: Several studies have suggested that migraineurs suffer from neurocognitive abnormalities, but this phenomenon and exact mechanisms remain controversial. In this study, we aimed to reevaluate visual spatial attention via event-related potential (ERP) examinations and explore further correlations between ERP data and migraine characteristics. METHODS: Altogether, 25 migraine patients (9 males, 16 females; mean age 35.240 years) in the interictal period and 21 age-matched healthy controls (8 males, 13 females; mean age 35.286 years) were recruited. A modified visual oddball paradigm which contained standard, target and novel stimuli was used in the test, and amplitudes and latencies of corresponding original/difference ERP components were measured and analyzed independently. RESULTS: We found that P3 amplitude was markedly reduced in migraineurs. This phenomenon was further validated in analysis of difference P3 components (target minus standard and novel minus standard). Additionally, the N1 and N2 latencies elicited by novel stimulus were both delayed in patients compared with controls. Furthermore, these deviant cognitive ERPs were correlated with frequency and duration of migraine attacks. CONCLUSIONS: These results indicated impaired visual spatial attention in migraine patients, which could be related to frequency and duration of attacks.


Assuntos
Atenção/fisiologia , Potenciais Evocados/fisiologia , Transtornos de Enxaqueca/fisiopatologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
ChemSusChem ; 12(11): 2385-2392, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-30838795

RESUMO

Solution-processed organic-inorganic lead halide perovskites have shown photovoltaic performance above 23 %, attracting great attention. However, the champion devices require fabrication in a controlled inert/dry atmosphere. The development of highly efficient and stable perovskite solar cells under high-humidity atmosphere conditions for future commercialization is still challenging, especially for CH3 NH3 PbI3 (MAPbI3 ), which is vulnerable to moisture. In this study, a large-sized tert-butylammonium [C(CH3 )3 NH3 + ] organic cation was incorporated into the MAPbI3 crystalline structure, which could form a more stable 3 D crystalline structure and alleviate the decomposition caused by the humidity. It delivered a power conversion efficiency of 19.3 % upon preparation under a humid environment condition of 50 % relative humidity as well as improved humidity and thermal stability. Our work provides a facile strategy for improving perovskite performance and stability by introducing a new chemical additive for the future application of perovskite solar cells.

8.
Chemosphere ; 224: 519-526, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30831504

RESUMO

The batch experiments were conducted to understand sorption process of bithionol (BIT) in yellow soil (YS) and red soil (RS), while column leaching experiments were performed to evaluate the leaching behavior of BIT and levamisole (LEV) in the tested soils. The adsorption and desorption data fitted well with the Freundlich isotherms (R2 ≥ 0.94). The distribution coefficient of BIT in the YS and RS were 104 and 98.3 L/kg, respectively. Hysteresis was observed for bithionol desorption in the YS and RS, with hysteresis coefficient of 0.917 and 0.928, respectively. Dissolved organic matter (DOM) addition and acid condition enhanced the adsorption of BIT in the soil. Both BIT and LEV showed poor leaching potential in the tested soils. More than 80% of BIT and LEV remained in the surface soil layer and the amount of the two target compounds in the leachates accounted for less than 1% of overall recovery. DOM showed little influence on the concentration of BIT and LEV in the leachates collected at different time. The results could fill the gap on the behavior of BIT and LEV in soil under laboratory conditions.


Assuntos
Bitionol/química , Levamisol/química , Poluentes do Solo/química , Solo/química , Adsorção
9.
J Clin Neurosci ; 2018 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-30327224

RESUMO

Attention deficits have been demonstrated in migraine patients during the interictal period, but these findings are not consistent across all studies. These inconsistencies may arise due to the different aspects of attention measured by various psychometric tests. Current theories divide attention into three separate domains subserved by separate networks: alerting, orienting, and executive control. The attention network test (ANT) was developed to measure all three attention networks and so may reveal more specific attention deficits among migraineurs. The aim of this study was to evaluate the attention function of migraine without aura (MwoA) patients using a series of neuropsychological scales and the ANT, and to assess the relationships between attention function and headache characteristics (e.g., history, frequency, and duration of each attack). Our results showed that MwoA patients exhibited significantly longer response times (RTs) of the executive control network, whereas no significant differences were observed in alerting and orienting network RTs between groups. MwoA patients also exhibited poorer performance than health control (HC) on the Stroop III and Shape Trail test B (STT B) tests. Spearman's analysis revealed positive correlations between executive control network RTs and both frequency and duration of migraine attack. MwoA patients demonstrate impairments of the executive control network, which appear to be exacerbated by more frequent and longer migraine attacks.

10.
Med Sci Monit ; 24: 5355-5362, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30067608

RESUMO

BACKGROUND The influence of type 2 diabetes mellitus (T2DM) on attention has been elusive. The Attention Network Test (ANT) was developed to evaluate the functioning of 3 individual attentional networks: orienting, alerting, and executive control. The purpose of this study was to use the ANT to assess attentional function and its sub-components in T2DM patients ages 40-60 years. MATERIAL AND METHODS Thirty T2DM patients and 30 healthy controls ages 40-60 years were recruited in this investigation. The ANT was used to statistically compare the efficiency among 3 sub-components of the attention networks between middle-aged T2DM patients (n=30) and gender-, age-, and education-matched healthy controls (n=30). RESULTS The ANT demonstrated a significant difference in executive control network between the T2DM patients and healthy controls (t=3.242, P=0.002), whereas no significant difference was observed regarding the domains of alerting (t=0.515, P=0.609) and orienting control (t=0.078, P=0.938) between the T2DM patient group and the healthy control group. Moreover, the mean reaction time in the ANT in the T2DM patients was significantly longer compared with that in the healthy controls (t=3.561, P=0.001). CONCLUSIONS The ANT reveals significant impairment in the executive control of middle-aged patients diagnosed with T2DM, whereas no significant impairment was observed in the domains of alerting and orienting.


Assuntos
Atenção/fisiologia , Função Executiva/fisiologia , Orientação/fisiologia , Adulto , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiopatologia , Testes Neuropsicológicos , Tempo de Reação
11.
J Ethnopharmacol ; 226: 36-43, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30063973

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Dryopteris fragrans (L.) Schott is a deciduous perennial herb, which has been used traditionally for treatment of ringworm infections and others skin diseases in the north of China. AIM OF THE STUDY: To characterize the chemical composition, evaluate the antifungal activity and explore possible mechanisms about action of ethanol extracts of D. fragrans. MATERIALS AND METHODS: The chemical components in the ethanol extracts of D. fragrans were detected by high-performance liquid chromatography coupled with electrospray ionization and quadruple time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS/MS). The minimal inhibitory concentrations (MIC) and minimal fungicidal concentrations (MFC) of the ethanol extracts of D. fragrans were determined by the Clinical and Laboratory Standards Institute (CLSI) M38-A2 method against 62 isolates of dermatophytes. The kinetics of fungal kill, synergy testing by checkerboard dilution and quantitation of sterol by ultra-performance liquid chromatography (UPLC) on Trichophyton rubrum and Trichophyton mentagrophytes were also investigated. RESULTS: Fourteen derivatives of phloroglucinol were identified in the ethanol extracts of D. fragrans. The MIC of the ethanol extracts of D. fragrans ranged from 0.059 to 3.780 mg/mL while MFC ranged from 0.118 to 3.780 mg/mL. The ethanol extracts of D. fragrans exerted fungicidal activity after 12 h of incubation against Trichophyton rubrum while it required 36 h of incubation against Trichophyton mentagrophytes at concentrations of 8 × MIC. In synergy testing, the interaction between miconazole (MCZ) and terbinafine (TBF) with the ethanol extracts of D. fragrans proved to be indifferent by testing fractional inhibitory concentration (FIC) values. Sterol in samples of fungal cells treated with the ethanol extracts of D. fragrans was significantly reduced. CONCLUSIONS: The ethanol extracts of D. fragrans had antifungal and fungicidal activity against dermatophytes and was likely a strain-dependent fungicidal agent. Interaction between drugs was indifferent on tested isolates. The inhibition of ergosterol biosynthesis was one of the antifungal mechanisms of the ethanol extracts of D. fragrans. These results showed that the ethanol extracts of D. fragrans could be explored for promising antifungal drugs. Dozens of phloroglucinol derivatives may contribute to high antifungal activity of the ethanol extracts of D. fragrans.


Assuntos
Antifúngicos/farmacologia , Dryopteris , Extratos Vegetais/farmacologia , Trichophyton/efeitos dos fármacos , Etanol/química , Testes de Sensibilidade Microbiana , Solventes/química , Trichophyton/crescimento & desenvolvimento
12.
Artigo em Inglês | MEDLINE | ID: mdl-29876852

RESUMO

In order to investigate level and potential sources of polycyclic aromatic hydrocarbons (PAHs) in wheat fields affected by coal combustion in Henan and Shaanxi Provinces and to investigate distribution and transfer of PAHs in winter wheat grown in the areas, various tissues of the crop and the corresponding rhizosphere soils were collected during the harvest season of winter wheat. The mean concentrations of USEPA 15 priority PAHs (sum of the three- to six-ring PAHs) ranged from 486 to 1117 µg kg-1 in the rhizosphere soils, indicating serious PAH contamination. Based on both the isomeric ratios of PAHs and a principal component analysis (PCA), the main sources of PAHs in the agricultural soils were from combustion of biomass, coal and petroleum, and petroleum. ∑15PAHs were significantly (p < 0.001) higher in the roots (287-432 µg kg-1) than those in aerial tissues (221-310 µg kg-1). There were two decreasing gradients of PAH concentrations, one from roots, stems to leaves, and the other from glumes to grains. Regardless of sampling sites, most PAHs detected in the roots and in the aerial tissues were three-ring PAHs (acenaphthene, acenaphthylene, fluorene, phenanthrene, and anthracene) and the percentages of three-ring PAHs were much higher in the aerial tissues (72.5-82.7%) than in the roots (49.5-74.0%) and in the rhizosphere soils (36.3-65.7%). The distribution of PAHs with different ring numbers in the stems, leaves, and glumes was quite similar to each other but was significantly different from that of the roots and rhizosphere soils. Combined with significant results from partial correlation and linear regression models, the present study suggested that partial three- to four-ring PAHs in the aerial tissues are derived from root-soil uptake and that six-ring PAHs may come from the air-to-leaf pathway, although the quantity contribution of foliar uptake and root uptake was yet to be further studied.

13.
Biomed Res Int ; 2018: 5193067, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29854763

RESUMO

Background: Pancreatic cancer (PC) is a deadly disease with poor prognosis in the general population. We aimed to quantitate overall survival of patients with PC after irreversible electroporation (IRE) and the incidence of relevant complications. Methods: We performed a literature search via five electronic databases (PubMed, Embase, Web of Science, Scopus, and Cochrane Library databases) up to August 2017. The primary outcomes were overall survival and prognosis. Secondary outcomes included the response of post-IRE complications. Fixed-effects or random-effects meta-analysis was conducted to pool these data. Results: A total of 15 eligible articles involving 535 patients were included. The primary outcomes showed that the pooled prevalence estimates of overall survival were 94.1% (95% CI: 90.7-97.5), 80.9% (95% CI: 72.5-89.4), 54.5% (95% CI: 38.3-70.6), and 33.8% (95% CI: 14.2-53.5) at 3, 6, 12, and 24 months, and the pooled prevalence data of complete response (CR) at 2 months, partial response (PR) at 3 months, and progression at 3 months were 12.5% (95% CI: 2.9-22.2), 48.5% (95% CI: 39.4-57.6), and 19.7% (95% CI: 7.3-32.2), respectively. The secondary outcomes showed that the pooled prevalence values of post-IRE complications were abscess 6.6% (95% CI: 0.2-13), fistula 10.6% (95% CI: 2.5-18.7), pain 33.5% (95% CI: 14.5-52.5), infection 16.1% (95% CI: 3.9-28.4), thrombosis 4.9% (95% CI: 1.2-8.5), pancreatitis 7.2% (95% CI: 3.1-11.2), bleeding 4.2% (95% CI: -0.5-8.9), cholangitis 4.2% (95% CI: -0.5-8.9), nausea 9.6% (95% CI: 4.4-14.8), biliary obstruction 13.8% (95% CI: 4.2-23.3), chest tightness 7.6% (95% CI: 0.5-14.6), and hypoglycemia 5.9% (95% CI: -0.4-12.2). Conclusions: This meta-analysis indicated a clear survival benefit for PC patients who received irreversible electroporation therapy, although future safety and effectivity monitoring from more large-scale studies will be needed.


Assuntos
Eletroporação , Neoplasias Pancreáticas/terapia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento
14.
Environ Sci Pollut Res Int ; 25(19): 18947-18959, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29717431

RESUMO

To identify status, source of polycyclic aromatic hydrocarbons (PAHs) in urban soils and to assess soil environmental quality in Xi'an City, China, total 45 soil samples were collected from surface layer (0-10 cm) in different functional areas. Total concentrations of 16 US EPA priority PAHs ranged from 149.9 to 5770 µg kg-1, with a mean of 1246 µg kg-1. High molecular weight (HMW) PAHs accounted for the majority (42.4-72.2%) of the total PAHs in the urban soils, and phenanthrene (Phe), fluorene (Flo), pyrene (Pyr), benzo(b)fluoranthene (BbF), and chrysene (Chr) were the major compounds. Concentrations of PAHs varied among different functional areas. High level of PAHs was particularly apparent in industrial zones and city road overpass, while low level was recorded in scenic spots and campus. The integration of isomer ratios, principal component analysis (PCA), and positive matrix factor (PMF) indicated that the sources of PAHs in Xi'an urban soils were mainly derived from vehicle emissions and coal combustion. Based on incremental lifetime cancer risks (ILCR) model, the urban soils from the three functional areas (industrial zone, urban road, and city road overpass) posed potential cancer risk, and the cancer risks of direct ingestion for children were apparently higher than that for adolescence and for adult, respectively. Therefore, attention should be paid to the health risk for children exposed to PAHs in the urban soils.

15.
ChemSusChem ; 11(9): 1467-1473, 2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29626389

RESUMO

Inverted perovskite solar cells (PSCs) with a p-i-n structure have attracted great attention. Normally, inorganic p-type metal oxides or polymers are used as the hole-transport material (HTM), a vital component in the inverted PSCs. However, this type of HTM often requires high processing temperatures and/or high costs. On the other hand, a commonly used organic HTM, poly(3,4-ethylenedioxythiophene polystyrene sulfonate (PEDOT:PSS), is sensitive to humidity and thus affects the stability of the PSCs. Herein, we employ a small molecule, 4,4',4''-tris(N-3-methylphenyl-N-phenylamino) triphenylamine (m-MTDATA) to replace PEDOT:PSS as a new HTM for inverted PSCs. Compared to a PEDOT:PSS-based device, m-MTDATA-based PSCs exhibit enhanced performance. The highest power conversion efficiency (PCE) was notably improved from 13.44 % (PEDOT:PSS) to 18.12 % (m-MTDATA), suggesting that m-MTDATA could be an efficient HTM to achieve high performance inverted PSCs. Furthermore, the m-MTDATA-based device demonstrated improved stability (retaining 90 % PCE) under ambient conditions over 1000 h compared with the PEDOT:PSS-based devices (retaining 40 % PCE).

16.
ACS Appl Mater Interfaces ; 10(17): 14922-14929, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29633612

RESUMO

Organic-inorganic metal halide perovskite solar cells (PSCs) have been emerging as one of the most promising next generation photovoltaic technologies with a breakthrough power conversion efficiency (PCE) over 22%. However, aiming for commercialization, it still encounters challenges for the large-scale module fabrication, especially for flexible devices which have attracted intensive attention recently. Low-temperature processed high-performance electron-transporting layers (ETLs) are still difficult. Herein, we present a facile low-temperature synthesis of crystalline SnO2 nanocrystals (NCs) as efficient ETLs for flexible PSCs including modules. Through thermal and UV-ozone treatments of the SnO2 ETLs, the electron transporting resistance of the ETLs and the charge recombination at the interface of ETL/perovskite were decreased. Thus, the hysteresis-free highly efficient rigid and flexible PSCs were obtained with PCEs of 19.20 and 16.47%, respectively. Finally, a 5 × 5 cm2 flexible PSC module with a PCE of 12.31% (12.22% for forward scan and 12.40% for reverse scan) was fabricated with the optimized perovskite/ETL interface. Thus, employing presynthesized SnO2 NCs to fabricate ETLs has showed promising for future manufacturing.

17.
Neuroreport ; 29(7): 564-569, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29481523

RESUMO

Synapse dysfunction is an early hallmark of Alzheimer's disease (AD), and was considered to be closely related to memory loss. The molecular mechanisms that trigger synapse loss and dysfunction remain poorly understood. Increasing evidence shows a link between Rho GTPases and synapse plasticity. Rho GTPases play a role in controlling synapse function by regulating actin cytoskeleton and dendritic spines. Observations have suggested that phytochemicals, such as flavonoids, alleviate cognition impairment in AD. However, to date, the link between the protective effect of flavonoids on AD and the activity of Rho GTPases remains uninvestigated. In this study, APP/PS1 mice were used as an AD model, and we found that synapse loss occurred in AD mice brain. Flavonoids extracted from leaves of Diospyros kaki (FLDK) were used to investigate whether its protective effects on synapse were related to Rho GTPases activity in AD mice. The Rho GTPases Activation Kit showed that Ras homologous member A (RhoA)-GTP was significantly higher and Ras-related C3 botulinum toxin substrate 1 (Rac1)-GTP was significantly lower in APP/PS1 mice than in normal mice, and RhoA-GTP activity was significantly inhibited by FLDK. We also found that FLDK improved learning and memory function, and antagonized the downregulation expressions of synapse-related proteins such as synaptophysin and drebrin. These findings suggest that FLDK is a potential therapeutic agent for AD, and modulation of Rho GTPases activity might contribute toward its protective effect.

18.
Proc Natl Acad Sci U S A ; 115(11): 2693-2698, 2018 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-29483255

RESUMO

Environmental legislation and proper implementation are critical in environmental protection. In the past, beehive coke ovens (BCOs) were popular in China, resulting in enormous emissions of benzo[a]pyrene (BaP), a common indicator of carcinogenic polycyclic aromatic hydrocarbons. BCOs were banned by the Coal Law in 1996. Although BCO numbers have declined since the ban, they were not eliminated until 2011 due to poor implementation. Here, we present the results of a quantitative evaluation of the health effects of historical BCO operation, the health benefits of the ban, and the adverse impacts of the poor implementation of the ban. With only limited official statistics available, historical and geospatial data about BCOs were reconstructed based on satellite images. Emission inventories of BaP from BCOs were compiled and used to model atmospheric transport, nonoccupational population exposure, and induced lung cancer risk. We demonstrated that more than 20% of the BaP in ambient air was from BCOs in the peak year. The cumulative nonoccupational excess lung cancer cases associated with BaP from BCOs was 3,500 (±1,500) from 1982 to 2015. If there was no ban, the cases would be as high as 9,290 (±4,300), indicating the significant health benefits of the Coal Law. On the other hand, if the ban had been fully implemented immediately after the law was enforced in 1996, the cumulative cases would be 1,500 (±620), showing the importance of implementing the law.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/legislação & jurisprudência , Indústria do Carvão Mineral/instrumentação , Indústria do Carvão Mineral/legislação & jurisprudência , Coque/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/prevenção & controle , Benzo(a)pireno/análise , Benzo(a)pireno/toxicidade , China , Coque/toxicidade , Monitoramento Ambiental/legislação & jurisprudência , Humanos
19.
Chemosphere ; 196: 45-52, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29291513

RESUMO

To evaluate the distribution patterns, degrees of contamination, and ecological risks of 15 metals (Cd, Pb, Sb, Sn, Tl, Mo, Cr, Mn, Ni, Cu, Zn, As, V, Co, and Se), a total of 26 paired water and sediment samples as well as 7 fish samples were collected in Jinjiang River, Chengdu, China. The metal forms of the sediments were analyzed using BCR three-step sequential extraction procedures, and the metal contents of the samples were determined by ICP-MS. Four environmental indices including the geo-accumulation index, bioconcentration factor, biota-sediment accumulation factor, and the potential ecological risk index were calculated to evaluate pollution level and eco-risk of the metals. Based on the current study, Mn and Cd were preferentially associated with the exchangeable fraction, Cu and Pb were primarily in the reducible fraction, while the other metals were mainly found in the residual fraction. With the exception of Sb and Mo, the BCF values of the metals were greater than 100, especially for Zn, which had the highest BCF value (74200), suggesting that these metals had higher bioconcentration ability. Based on the geo-accumulation index and the potential ecological risk index (RI) calculated in this study, the middle reaches of Jinjiang River present moderate to severe metal pollution, and moderate to considerable potential ecological risk, especially for the risk of Cd, which should be paid more attention in the future. While non-pollution level and low ecological risk of the metals were found in the upper and lower reaches of Jinjiang River.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Animais , China , Ecologia , Poluição Ambiental , Peixes/metabolismo , Sedimentos Geológicos/química , Metais Pesados/metabolismo , Medição de Risco , Rios/química , Poluentes Químicos da Água/metabolismo
20.
Brain Res ; 1678: 85-93, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29038004

RESUMO

Amyloid-ß peptide (Aß) initiates a cascade of pathological events, including activation of microglial cells, oxidative stress, and inflammation, leading to neuronal death and the typical pathological changes in Alzheimer's disease (AD). Flavonoids have been reported to exert neuroprotective activities, not only through their generally accepted antioxidant effects, but also through their ability to protect against neurotoxin-induced injury. Flavonoids reduce Aß production, inhibit neuroinflammation, increase cerebrovascular function, and improve cognitive performance. Here, we analyzed the effects of a flavonoid-rich ethanol extract from the leaves of Diospyros kaki (FLDK) in APP/PS1 transgenic mice. We found that oral treatment with FLDK reversed learning and memory impairment, reduced Aß burden and expression of ß-site amyloid precursor protein cleavage enzyme 1 (BACE1), and decreased microglial activation in senile plaques. FLDK restored antioxidant enzyme activities, as well as reduced the lipid peroxidation product, malondialdehyde, and inflammatory mediators. These results demonstrate that FLDK alleviates cognitive decline and reduces Aß burden, microglial activation, oxidative stress, and inflammation responses. Thus, FLDK treatment may be a potential therapeutic strategy for preventing and treating AD, at least in part via its anti-oxidant and anti-inflammatory biological activities and its effect on the Aß producing enzyme BACE1.


Assuntos
Peptídeos beta-Amiloides/efeitos dos fármacos , Precursor de Proteína beta-Amiloide/efeitos dos fármacos , Flavonoides/farmacologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Cognição , Transtornos Cognitivos/tratamento farmacológico , Disfunção Cognitiva/tratamento farmacológico , Diospyros/metabolismo , Etanol/farmacologia , Flavonoides/uso terapêutico , Humanos , Transtornos da Memória/metabolismo , Camundongos , Camundongos Transgênicos , Microglia/metabolismo , Neuroimunomodulação/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta , Placa Amiloide/metabolismo , Presenilina-1/metabolismo
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