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1.
Sensors (Basel) ; 24(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38474978

RESUMO

The synergistic effects on the 0.18 µm PPD CISs induced by neutron displacement damage and gamma ionization damage are investigated. The typical characterizations of the CISs induced by the neutron displacement damage and gamma ionization damage are presented separately. The CISs are irradiated by reactor neutron beams up to 1 × 1011 n/cm2 (1 MeV neutron equivalent fluence) and 60Co γ-rays up to the total ionizing dose level of 200 krad(Si) with different sequential order. The experimental results show that the mean dark signal increase in the CISs induced by reactor neutron radiation has not been influenced by previous 60Co γ-ray radiation. However, the mean dark signal increase in the CISs induced by 60Co γ-ray radiation has been remarkably influenced by previous reactor neutron radiation. The synergistic effects on the PPD CISs are discussed by combining the experimental results and the TCAD simulation results of radiation damage.

2.
Huan Jing Ke Xue ; 41(7): 3102-3111, 2020 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608882

RESUMO

To explore the variation of mercury in the atmosphere in Suzhou, continuous monitoring of gaseous element mercury (GEM), gaseous oxidized mercury (GOM), and particulate bound mercury (PBM) was conducted from January 1 to December 31, 2018, in Suzhou. The weights trajectory analysis method (CWT) and concentration rose were used to analyze the atmospheric mercury sources and concentration variation. The results showed that during the monitoring period, the concentration ranges of GEM, GOM, and PBM in Suzhou were 0-53.3 ng·m-3, 0-256 pg·m-3, and 0-5208 pg·m-3, respectively. The corresponding annual average concentrations of the three mercury species were (2.57±2.09) ng·m-3, (5.27±15.7) pg·m-3, and (16.0±157) pg·m-3, respectively. GEM was the main component of atmospheric mercury in Suzhou. During the monitoring period, the average concentration of GEM in Suzhou was highest in winter, higher in spring than in autumn, and lowest in summer. According to the CWT, the mercury-containing air mass in spring and winter predominantly originated from inland; in summer, it mainly originated from the local area, the Yellow Sea, and the East China Sea, and in autumn from inland, the Yellow Sea, and the Bohai Sea. The wind and mercury rose charts showed that atmospheric mercury concentrations were higher from inland and lower from the ocean. During the monitoring period, the average concentrations of GEM and PBM in Suzhou were lower during the day than the night. The diurnal variation of GEM and PBM was significantly and strongly correlated with solar radiation, humidity, and air temperature. The average concentration of GOM showed multiple peaks and valleys in one day. Some peaks were caused by fuel oil combustion emissions, and some by O3 oxidation with GEM.

3.
ACS Appl Mater Interfaces ; 12(12): 14064-14070, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32125818

RESUMO

One-dimensionally (1D) hollow noble meal nanotubes are attracting continuous attention because of their huge potential applications in catalysis and electrocatalysis. Herein, we successfully synthesize hollow iridium nanotubes (Ir NTs) with the rough porous surface by the 1-hydroxyethylidene-1, 1-diphosphonic acid-induced self-template method under hydrothermal conditions and investigate their electrocatalytic performance for oxygen evolution (OER) and nitrate reduction reactions (NO3-RR) in an acidic electrolyte. The unique 1D and porous structure endow Ir NTs with big surface areas, high conductivity, and optimal atom utilization efficiency. Consequently, Ir NTs exhibit significantly enhanced activity and durability for acidic OERs compared with commercial Ir nanocrystals (Ir c-NCs), which only require the overpotential of 245 mV to deliver the current density of 10 mA cm-2. Meanwhile, Ir NTs also show higher electrocatalytic activity for NO3-RR than that of Ir c-NCs, such as a Faraday efficiency of 84.7% and yield rate of 921 µg h-1 mgcat-1 for ammonia generation, suggesting that Ir NTs are universally advanced Ir-based electrocatalysts.

4.
J Pharm Biomed Anal ; 157: 44-58, 2018 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-29758469

RESUMO

Ilex rotunda, in which triterpenoids and phenylpropanoids are major bioactive constituents, has been widely used in traditional Chinese medicines. In this study, a validated UPLC/Q-TOF-MS/MS method was developed to simultaneously identify and quantify the triterpenoids and phenylpropanoids in the stem bark, fruit, leaves, roots and stem xylem of this herbal medicine. A total of seventy triterpenoids and twelve phenylpropanoids were identified with the assistance of the modified mass defect filter and key product ion filter data processing strategies, and forty-eight of them were confirmed by reference substances. Meanwhile, the contents of twelve triterpenoids and three phenylpropanoids in the five plant parts were determined with good linearity (R2 ≥ 0.9993), precision (RSD ≤ 2.04%), repeatability (RSD ≤ 1.99%), stability (RSD ≤ 1.88%) and recovery (96.65-103.17% and RSD ≤ 3.54%). Furthermore, PCA and OPLS-DA methods were employed to visualize the relationships and discrimination of the forty-two stem bark samples from two origins based on the contents of fifteen analytes. Our findings may provide early scientific evidence for quality control and for elucidating the therapeutic principle of Ilex rotunda.


Assuntos
Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Ilex/química , Triterpenos/química , Cromatografia Líquida de Alta Pressão/métodos , Estudos de Avaliação como Assunto , Medicina Tradicional Chinesa/métodos , Controle de Qualidade , Espectrometria de Massas em Tandem/métodos
5.
ACS Appl Mater Interfaces ; 10(23): 19755-19763, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29799726

RESUMO

Rationally designing and manipulating composition and morphology of precious metal-based bimetallic nanostructures can markedly enhance their electrocatalytic performance, including selectivity, activity, and durability. We herein report the synthesis of bimetallic PtRh alloy nanodendrites (ANDs) with tunable composition by a facile complex-reduction synthetic method under hydrothermal conditions. The structural/morphologic features, formation mechanism, and electrocatalytic performance of PtRh ANDs are investigated thoroughly by various physical characterization and electrochemical methods. The preformed Rh crystal nuclei effectively catalyze the reduction of Pt2+ precursor, resulting in PtRh alloy generation due to the catalytic growth and atoms interdiffusion process. The Pt atoms deposition distinctly interferes in Rh atoms deposition on Rh crystal nuclei, resulting in dendritic morphology of PtRh ANDs. For the ethanol oxidation reaction (EOR), PtRh ANDs display the chemical composition and solution pH co-dependent electrocatalytic activity. Because of the alloy effect and particular morphologic feature, Pt1Rh1 ANDs with optimized composition exhibit better reactivity and stability for the EOR than commercial Pt nanocrystals electrocatalyst.

6.
Pharmacogenomics ; 19(5): 495-511, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29517418

RESUMO

Recent studies have suggested that genomic diversity may play a key role in different clinical outcomes, and the importance of SNPs is becoming increasingly clear. In this article, we summarize the bioactivity of SNPs that may affect the sensitivity to or possibility of drug reactions that occur among the signaling pathways of regularly used immunosuppressants, such as glucocorticoids, azathioprine, tacrolimus, mycophenolate mofetil, cyclophosphamide and methotrexate. The development of bioinformatics, including machine learning models, has enabled prediction of the proper immunosuppressant dosage with minimal adverse drug reactions for patients after organ transplantation or for those with autoimmune diseases. This article provides a theoretical basis for the personalized use of immunosuppressants in the future.


Assuntos
Imunossupressores/uso terapêutico , Polimorfismo de Nucleotídeo Único/genética , Resultado do Tratamento , Biologia Computacional , Humanos , Medicina de Precisão , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
7.
Zhongguo Zhong Yao Za Zhi ; 42(3): 456-464, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-28952249

RESUMO

Internal transcript spacer 2 (ITS2) is one of the broadly used standard core barcodes and also the only nuclear barcode in identification of Chinese traditional medicine. Although the DNA barcode method based on ITS2 is popular and has been used in Chinese Pharmacopoeia, its low discriminatory efficiency is still a problem to its extensive application. Therefore, further study is still necessary to explore its phylogenetic information for medicinal plants identification. In cells, ITS2 activity is based on its secondary structure. The secondary structures are particularly useful in phylogenetic analysis because they include information not found in the primary sequence. In this study ITS2 secondary structure of 40 samples from 26 species were predicted and used to explore their utility in addressing the identification problems of Chinese traditional medicine in Solanum. The secondary structures were predicted and aligned, and their consensus models were generated using the three different software of LocARNA, MASTR and PicXAA-R. RNAstat software was used to transform the secondary structures into 28 symbol code data for maximum parsimony (MP) analysis. The results showed that the phylogenetic information increased 88.57% after ITS2 secondary structure information has been added, and then the support values above 50%, 75% and 90% in the tree increased 19.05%, 66.67% and 66.67%, respectively, indicating that the identification of Solanum medical plants has been well resolved. Thus, our analysis suggests that ITS2 secondary structure information should be incorporated into the current DNA barcoding analysis as a beneficial supplement of phylogenetic information.


Assuntos
Código de Barras de DNA Taxonômico , DNA Espaçador Ribossômico/genética , Filogenia , Solanum/genética , DNA de Plantas/genética , Conformação de Ácido Nucleico , Plantas Medicinais/genética
8.
Anal Biochem ; 525: 100-106, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28263739

RESUMO

Microfluidic paper-based analytical devices (µPADs) have a significant potential in developing portable and disposable point-of-care testing (POCT). Herein, a facile, rapid, cost-effective and environment friendly strategy for µPADs fabrication is proposed. Specifically, the substrate paper was hydrophobized by coating with trimethoxysilane (TOS), and then the selected area was hydrophilized by treating with surfactant. The whole fabrication process was implemented within 7 min, with no need for complex pre-treatment, high-temperature and special equipment. As a proof-of-concept application, the as-prepared µPAD was applied to determination of the glucose content in human serum samples. The results agreed well with those obtained by a glucometer. We believe that the µPADs fabrication method proposed here could provide a facile, rapid and low-cost reference for other related studies.


Assuntos
Glicemia/análise , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Papel , Desenho de Equipamento , Humanos , Interações Hidrofóbicas e Hidrofílicas , Sistemas Automatizados de Assistência Junto ao Leito
9.
Appl Microbiol Biotechnol ; 97(3): 1141-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22419217

RESUMO

Previously, we studied an AAVS1 site-specific non-viral integration system with a Rep-donor plasmid and a plasmid containing adeno-associated virus integration element. Our earlier study focused on the plasmid vector itself, but the cellular response to the system was still unknown. SP100 is a member of the promyelocytic leukemia nuclear bodies. It is involved in many cellular processes such as transcriptional regulation and the cellular intrinsic immune response against viral infection. In this study, we revealed that SP100 inhibited the Rep-dependent nonviral integration. Conversely, transient expression of Rep78 increased the degradation of SP100. This degradation was inhibited by treatment with MG132, an inhibitor of the ubiquitin proteasome. SP100 and Rep78 are both located in the nucleolus, which provides the spatial possibility for their interaction. Rep78 was coimmunoprecipitated with the enhanced green fluorescent protein (EGFP)-SP100 fusion protein but not EGFP, which verified the interaction between Rep78 and SP100. These results have enriched our knowledge about the cellular protein SP100 and Rep-dependent nonviral integration. It may lead to an improvement in the application of Rep-related transgene integration method and in the selection of target cells.


Assuntos
Antígenos Nucleares/metabolismo , Autoantígenos/metabolismo , Dependovirus/fisiologia , Integração Viral , Linhagem Celular , Proteínas de Ligação a DNA/metabolismo , Dependovirus/genética , Humanos , Plasmídeos , Ligação Proteica , Proteínas Virais/metabolismo
10.
Eur Neurol ; 65(2): 94-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21273777

RESUMO

BACKGROUND: Pyrexia is often associated with unfavorable stroke outcomes. However, limited information is available on the relationship between the causes of poststroke hyperthermia and stroke prognosis, especially for mild-to-moderate neurogenic pyrexia in acute cerebral infarction. AIMS: To compare the differences in the clinical features and characteristics of pyrexia as well as its prognosis among acute cerebral infarction patients with mild-to-moderate neurogenic pyrexia, with infectious pyrexia, and without pyrexia. The focus was on mild-to-moderate neurogenic pyrexia. METHODS: A total of 709 patients with acute cerebral infarction were prospectively recruited and their clinical data were analyzed. RESULTS: No significant difference was detected in age, gender, history of smoking, hypertension, or diabetes among the 3 groups (p > 0.05). Patients with mild-to-moderate neurogenic pyrexia and those with infectious pyrexia had higher baseline National Institutes of Health Stroke Scale (NIHSS) scores (15.1 ± 6.7, p = 0.003; 14.3 ± 8.1, p = 0.002, respectively), lower 3-month Barthel index (BI) values (64.2 ± 40.7, p < 0.001; 61.9 ± 49.3, p < 0.001, respectively) and higher 3-month mortality rates (13%, p = 0.026; 16%, p < 0.001, respectively) than patients without pyrexia (NIHSS score 11.4 ± 7.9; BI 82.6 ± 39.8, and mortality rate 6%, respectively). No difference existed in these parameters between the 2 pyrexia groups (p > 0.05), but mild-to-moderate neurogenic pyrexia had an earlier onset and a shorter duration than infectious pyrexia (p < 0.001). CONCLUSIONS: Acute cerebral infarction patients with mild-to-moderate neurogenic pyrexia had a similar prognosis compared to those with infectious pyrexia. Mild-to-moderate neurogenic pyrexia is possibly associated with stroke severity.


Assuntos
Infarto Cerebral/complicações , Febre/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Infarto Cerebral/mortalidade , Feminino , Febre/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
11.
Hum Gene Ther ; 21(6): 728-38, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20070175

RESUMO

The adeno-associated virus (AAV) p5 promoter controls expression of Rep68 and Rep78, which are responsible for specific integration of the viral genome into the AAVS1 site of the human genome. The p5 promoter contains a Rep-binding element (RBE) sequence that acts as a substrate of the Rep proteins for both site-specific integration of p5 itself and transcriptional suppression of the p5 promoter. To differentiate these two Rep-mediated functions, we dissected the p5 core structure TATA/RBE/YY1+1 through a series of mutations. Mutations in the TATA box or YY1+1 region of p5IEE significantly reduced Rep-mediated site-specific integration (RMSSI) and p5 promoter transcriptional activity, but only the TATA box is involved in Rep-mediated transcriptional suppression (RMTS). Point mutations at nucleotides 266, 267, 268, 270, and 273 of the GAGTGAGC motif in p5 RBE significantly reduced RMSSI efficiency. However, only p5G270T lost the affinity of Rep binding and had significant reduction of RMTS. It appears that RMTS is determined by the affinity of p5RBE for Rep whereas RMSSI requires more stringent conditions. Thus, RMTS and RMSSI can be differentiated by point mutations in the p5 promoter, which is useful in gene therapy in a helper vector to drive Rep expression, as the mutant promoters seldom integrate themselves but remain the RMTS feature for reduced cytotoxicity caused by a high level of Rep protein.


Assuntos
Sequências Reguladoras de Ácido Nucleico/genética , Sequência de Bases , Dependovirus/genética , Dependovirus/metabolismo , Expressão Gênica , Genoma Viral , Humanos , Ligação Proteica/genética , TATA Box
12.
J Chromatogr Sci ; 48(1): 7-11, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20056028

RESUMO

A new method using gel permeation chromatography (GPC) cleanup followed by ultra-performance liquid chromatography combined with tandem mass spectrometry (UPLC-MS-MS) has been established for simultaneous determination of 18 carbamate pesticides in nuts (chestnut and pine nut). Recoveries obtained by fortifying nut (spiking at 0.02 mg/kg) range from 70.21% to 89.56%. The proposed method features good sensitivity. Its limits of quantification are low enough to allow pesticide residues to be determined at concentrations below the maximum residue levels legally accepted. The precision, expressed as relative standard deviation, ranges from 2.26% to 4.07%.


Assuntos
Carbamatos/análise , Cromatografia em Gel/métodos , Cromatografia Líquida de Alta Pressão/métodos , Nozes/química , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia em Gel/economia , Cromatografia Líquida de Alta Pressão/economia , Fagaceae/química , Limite de Detecção , Pinus/química , Espectrometria de Massas em Tandem/economia , Fatores de Tempo
13.
Zhonghua Nei Ke Za Zhi ; 47(12): 988-90, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19134300

RESUMO

OBJECTIVE: To investigate whether systemic inflammatory response syndrome (SIRS) after cerebral infarction is associated with poor outcome and its associated clinical factors. METHODS: We prospectively studied 500 patients with cerebral infarction, recorded the associated clinical factors on presentation and calculated the mortality at 21st day. RESULTS: There are 85 SIRS patients in 500 patients with cerebral infarction, 31 with total anterior cerebral infarction (TACI), 34 with partial anterior cerebral infarction (PACI), 15 with posterior cerebral infarction (POCI) and 5 with lacunar cerebral infarction (LACI). The frequency of SIRS was positively correlated with mortality rate according to Oxfordshire Community Stroke Project (OCSP) subtypes in cerebral infarction patients with fever (Spearman correlation coefficient = 1.0; P < 0.001). Single factor analysis showed that the risk factors for both SIRS and mortality of cerebral infarction were as follows: age, infection, 48 h Chinese Stroke Scale score, 48 h Glasgow score, OCSP subtypes and dysphagia. Diabetes was the risk factor for SIRS, but had no effect on mortality. On Cox regression, 48 h Glasgow score was the sole independent risk factor of outcome. However, if SIRS was included in the formula, P > 0.05. CONCLUSIONS: SIRS is the predictor of poor outcome after acute cerebral infarction. It is important to prevent SIRS especially in TACI and POCI. Diabetes is the risk factor for SIRS, but has no effect on mortality.


Assuntos
Infarto Cerebral/complicações , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco
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