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1.
Front Microbiol ; 14: 1326837, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38420214

RESUMO

Acute pancreatitis is caused by trypsinogen activation in acinar cells caused by various injury forms (gallstone, high triglycerides, alcohol, etc.). Viral pancreatitis is a clinically rare disease type, which is easily neglected by clinicians and causes serious adverse consequences. Viral pancreatitis involves the entry of viruses into pancreatic cells, triggering inflammation, immune response activation, and enzymatic autodigestion, leading to tissue damage and potential complications. At present, there are few available reports on viral pancreatitis, most of which are case reports. This review brings attention to clinicians by describing the incidence of viral pancreatitis to enhance clinical understanding and patient care.

2.
Int J Environ Health Res ; 28(2): 159-166, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29564918

RESUMO

This study aims to assess the relationship between risk perception, attitude, and avoidance among residents toward an urban incinerator in Taichung, Taiwan. A cross-sectional study was conducted and three schools were enrolled. The case group was composed of 514 residents who live near an incinerator. The control group was composed of 264 people nearly the same age and who have lived in that area basically the same period of time. All participants were interviewed using a structured questionnaire. Results of this study showed that there was no significant difference between the exposure group and the control group in risk perception and attitude regarding the incinerator. However, the exposure group showed a significantly higher desire to move within one year or move sometime in the future than the control group. Therefore, these people should encourage the Environmental Protection Administration (EPA) to do everything it can to make sure that the incinerator operates safely.


Assuntos
Aprendizagem da Esquiva , Exposição Ambiental , Conhecimentos, Atitudes e Prática em Saúde , Incineração , Medição de Risco , Resíduos Sólidos , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Percepção , Taiwan
3.
Chemosphere ; 168: 1669-1676, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27939669

RESUMO

A donor-acceptor-donor (D-A-D) type monomer (3,6-bis(2-(3,4-ethylenedioxy- thiophene))pyridazine) (EPE) with pyridazine as intermediate unit (acceptor) and 3,4-ethylenedioxythiophene (EDOT) as sealing unit (donor) was successfully synthesized. The functionalized multi-walled carbon nanotubes (f-MWCNT) was covalently linked with polymer chain via chemical oxidative polymerization of monomer EPE to form poly(EPE)/f-MWCNT composite. The prepared composite was characterized by Fourier transform infrared spectroscopy (FT-IR), Ultraviolet-visible absorption spectra (UV-vis), X-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDS), and Field emission scanning electron microscope (FESEM), respectively. The photocatalytic activity of poly(EPE)/f-MWCNT was investigated toward degrading methylene blue (MB) dye solution (1 × 10-5 M) under visible light irradiation. As expected, the degradation efficiency of poly(EPE)/f-MWCNT is significantly higher than that of either pure poly(EPE) or poly(EPE)/MWCNT for MB dye, especially the kinetic constant of poly(EPE)/f-MWCNT is more than 6 times of poly(EPE)/MWCNT. Besides, the reactive oxygen species trapping experiments indicate that the degradation of MB over the poly(EPE)/f-MWCNT composite mainly results from holes oxidation. Moreover, the enhancement of the photodegradation rate is mainly attributed to the superior stability, strong light absorption ability, and highly effective photo-generated electron-hole pairs of the poly(EPE)/f-MWCNT composite. A reasonable mechanism for the enhanced reactivity was proposed.


Assuntos
Azul de Metileno/química , Nanotubos de Carbono/química , Polímeros/química , Catálise/efeitos da radiação , Luz , Fotólise , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Tiofenos/química , Difração de Raios X
4.
Biomed Chromatogr ; 30(2): 269-79, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26138785

RESUMO

Huan-Nao-Yi-Cong-Fang (HNYCF) is a potential prescription in treating Alzheimer's disease. Seven constituents [ferulic acid (FA), 2,3,5,4'-tetrahydroxystilbene-2-O-ß-d-glucoside (THSG), berberine hydrochloride (BHCl), emodin, ginsenoside Rg1 (Rg1), ginsenoside Re (Re) and ginsenoside Rb1 (Rb1)] have been used as quality chemical markers of HNYCF owing to their biological significance and high contents in crude plant materials. This study explored the metabolites of the seven bioactive components in rat plasma to give useful data for further study of the action mechanism of HNYCF. LC/MS-IT-TOF was used to simultaneously characterize the metabolites of the seven components. Using the combination of MetID Solution 1.0 software and accurate mass measurements, the metabolites of HNYCF were reliably characterized. Their structures were elucidated based on the accurate MS(2) spectra and comparisons of their changes in accurate molecular masses and fragment ions with those of parent compounds. A total of five parent active compounds (BHCl, emodin, Rg1, Rb1 and Re) and 10 metabolites were found from the rat plasma 2 h after oral administration of HNYCF dosage, of which two metabolites of emodin were observed for the first time. The proposed metabolic pathways of the bioactive components in the rat plasma are helpful for further studies on the pharmacokinetics and real active compound forms of this drug.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas/métodos , Administração Oral , Animais , Berberina/sangue , Berberina/química , Berberina/farmacocinética , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacocinética , Emodina/sangue , Emodina/química , Emodina/farmacocinética , Ginsenosídeos/sangue , Ginsenosídeos/química , Ginsenosídeos/farmacocinética , Masculino , Ratos , Ratos Wistar
5.
Nanoscale Res Lett ; 10(1): 370, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26395203

RESUMO

In this study, poly(3,4-ethylenedioxythiophene)/thiophene-grafted graphene oxide (PEDOT/Th-GO) composites from covalently linking of Th-GO with PEDOT chains were prepared via in situ chemical polymerization with different weight percentage of Th-GO ranging between 40 and 70 % in reaction medium. The resulting composite materials were characterized using a various analytical techniques. The structural analysis showed that the composites displayed a higher degree of conjugation and thermal stability than pure PEDOT, and the weight percentage of Th-GO could affect the doping level, amount of undesired conjugated segments, and porous structure of composites. Electrochemical analysis suggested that the highest specific capacitance of 320 F g(-1) at a current density of 1 A g(-1) with good cycling stability (capacitance retention of 80 % at 1 A g(-1) after 1000 cycles) was achieved for the composite prepared from 50 wt% Th-GO content in reaction medium.

6.
Nanoscale Res Lett ; 10: 148, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25852437

RESUMO

The nanocomposite materials of poly(3,4-ethylenedioxythiophene)/graphene oxide (PEDOT/GO), poly(3,4-ethylenedioxythiophene)/MnO2 (PEDOT/MnO2), and poly(3, 4-ethylenedioxythiophene)/graphene oxide/MnO2 (PEDOT/GO/MnO2) were successfully prepared by facile and template-free solution method. The structure and morphology of nanonanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible absorption spectra (UV-vis), field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDX), respectively. The catalytic activities of nanocomposites were investigated through the degradation processes of methylene blue (MB) solution under dark, UV light, and nature sunlight irradiation, respectively. The results displayed that nanocomposites were successfully synthesized, and PEDOT/GO had higher conjugation length and doped degree than pure PEDOT. However, the introduction of MnO2 could lead to the reduction of conjugation length and doped degree in PEDOT/MnO2 and PEDOT/GO/MnO2 nanocomposites. The field emission scanning electron microscope (FESEM) analysis also showed that both MnO2 and GO had some effect on the morphology of nanocomposites. The catalytic activities of pure PEDOT and nanocomposites were in the order of PEDOT/GO/MnO2 > PEDOT/MnO2 > PEDOT/GO > pure PEDOT. Besides, the catalytic results also showed that the highest degradation efficiency of MB after 7 h occurred in the PEDOT/GO/MnO2 composite in three irradiation.

7.
Nanoscale Res Lett ; 9(1): 557, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25317104

RESUMO

In this study, a simple one-step template-free solution method was developed for the preparation of poly(3,4-ethylenedioxythiophene) (PEDOTs) with different morphologies by adjusting various ratios of oxidant (FeCl3·6H2O) to monomer (3,4-ethylenedioxythiophene (EDOT)). The results from structural analysis showed that the structure of PEDOT was strongly affected by the oxidant/monomer ratio, and the polymerization degree, conjugation length, doping level, and crystallinity of PEDOT decreased with increasing of the oxidant/monomer ratio. The morphological analysis showed that PEDOT prepared from an oxidant/monomer ratio of 3:1 displayed a special coral-like morphology, and the branches of 'coral' would adjoin or grow together with increasing content of oxidant in the reaction medium; consequently, the morphology of PEDOT changed from coral to sheets (at an oxidant/monomer ratio of 9:1). The electrochemical analysis proved that the PEDOT prepared from an oxidant/monomer ratio of 3:1 had the lowest resistance and the highest specific capacitances (174 F/g) at a current density of 1 A/g with a capacity retention rate of 74% over 1,500 cycles, which indicated that the PEDOT with a coral-like morphology could be applied as a promising electrode material for supercapacitors.

8.
PLoS One ; 9(4): e91315, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24705246

RESUMO

BACKGROUNDS: Recent explosion of biological data brings a great challenge for the traditional clustering algorithms. With increasing scale of data sets, much larger memory and longer runtime are required for the cluster identification problems. The affinity propagation algorithm outperforms many other classical clustering algorithms and is widely applied into the biological researches. However, the time and space complexity become a great bottleneck when handling the large-scale data sets. Moreover, the similarity matrix, whose constructing procedure takes long runtime, is required before running the affinity propagation algorithm, since the algorithm clusters data sets based on the similarities between data pairs. METHODS: Two types of parallel architectures are proposed in this paper to accelerate the similarity matrix constructing procedure and the affinity propagation algorithm. The memory-shared architecture is used to construct the similarity matrix, and the distributed system is taken for the affinity propagation algorithm, because of its large memory size and great computing capacity. An appropriate way of data partition and reduction is designed in our method, in order to minimize the global communication cost among processes. RESULT: A speedup of 100 is gained with 128 cores. The runtime is reduced from serval hours to a few seconds, which indicates that parallel algorithm is capable of handling large-scale data sets effectively. The parallel affinity propagation also achieves a good performance when clustering large-scale gene data (microarray) and detecting families in large protein superfamilies.


Assuntos
Algoritmos , Análise por Conglomerados , Biologia Computacional/métodos , Conjuntos de Dados como Assunto/estatística & dados numéricos , Bases de Dados de Proteínas/estatística & dados numéricos , Perfilação da Expressão Gênica/estatística & dados numéricos , Ensaios de Triagem em Larga Escala/estatística & dados numéricos , Humanos , Análise em Microsséries/estatística & dados numéricos , Família Multigênica , Proteínas/análise , Proteínas/metabolismo , Proteômica
9.
Artigo em Inglês | MEDLINE | ID: mdl-23367376

RESUMO

Detection of protein families in large scale database is a difficult but important biological problem. Computational clustering methods can effectively address the problem. Although there exist many clustering algorithms, most of them are just based on the threshold. Their computational performances are affected by the weight distribution greatly, and they are only valid for some special networks. A new network clustering algorithm, Markov Finding and Clustering (MFC), is proposed to cluster the proteins into their functionally specific families accurately in this paper. The MFC algorithm makes an improvement in the random walk process and reduces the affection of the noise on the clustering result. It has a good performance on these networks which are not well addressed by existing algorithms sensitive to the noise. Finally, experiments on the protein sequence datasets demonstrate that the algorithm is effective in the detection of protein families and has a better performance than the current algorithms.


Assuntos
Algoritmos , Proteínas/análise , Análise por Conglomerados , Cadeias de Markov , Proteínas/química
10.
J Hazard Mater ; 172(2-3): 809-17, 2009 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-19683872

RESUMO

The binding between heavy metals and corresponding ligands affects their chemical behavior and toxicity in soil environments. The mechanisms of competitive complexation and/or chelation between Cd(2+) free cations and preferential concentrations of Cl(-), SO(4)(2-), and fulvate anions were investigated in simulated soil solutions at pH 4.00, 5.00 and 6.00. The Cd(2+) concentrations were calculated by a proposed equation, simulated by MINTEQ software, and directly determined by ion chromatography (IC). When Cl(-)/Cd or Cl(-)/Cd with SO(4)(2-)/Cd molar ratios of 3.18 and 4.05, the differences among Cd(2+) concentrations calculated by equation, simulated by MINTEQ software, and directly determined by IC were not significant, but their differences were pH independent for considering Cl(-)/Cd molar ratio and pH dependent for Cl(-)/Cd and SO(4)(2-)/Cd molar ratios. When Cl(-)/Cd, SO(4)(2-)/Cd, and additional FA/Cd molar ratios of 3.18 and 4.05, the Cd(2+) concentrations calculated by equation were significantly larger than those simulated by MINTEQ and determined by IC because in simulation and determination of Cd(2+) concentrations by IC, the complexation of Cd(2+) with ligands to form CdCl(+), CdSO(4), FACd(+) and FA(2)Cd had been considered, whereas in calculation this complexation aspect was ignored. Though IC can be used to determine Cd(2+) concentration in rhizosphere soil solutions ion chromatographic peak of Cd(2+) in 0.1M HCl saturation extract of slightly acidic soil and in deionized distilled water saturation extract of acidic soils still may be shielded by the vicinal chromatographic peaks of Mg(2+) and Mn(2+), respectively. The Cd(2+) concentrations in rhizosphere soil solutions of acidic or slightly acidic soils calculated by equation and/or simulated by Model may thus be used as potential alternatives for those determined by IC.


Assuntos
Cádmio/análise , Solo/análise , Benzopiranos/química , Ligação Competitiva , Cádmio/química , Cloretos/química , Cromatografia por Troca Iônica , Concentração de Íons de Hidrogênio , Ligantes , Poluentes do Solo , Sulfatos/química
11.
J Agric Food Chem ; 55(21): 8640-9, 2007 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-17894455

RESUMO

The relationship between Pb uptake by leaf lettuce ( Lactuca sativa L.) and water-soluble low-molecular-weight organic acids (LMWOAs) in rhizosphere, as influenced by transpiration (high and low), has been studied. Studies were carried out by culturing lettuce plants grown for 2 weeks in pots filled with quartz sand mixed with anion-exchange resin and then for 30 days in a greenhouse. The potted lettuce plants were subjected to stress by the addition of Pb(NO 3) 2 solutions (100, 200, and 300 mg of Pb L (-1)) and by high and low transpiration treatments for another 10-day period. Blank experiments (without addition of Pb(NO 3) 2 solutions to the pots) were also run. There were no significant differences in the growth of the plants with the addition of Pb(NO 3) 2 solutions in either of the transpirations studies. Uptake of Pb by the shoots and roots of the plants was found to be proportional to the concentration of Pb solutions added, and more accumulation was observed in the roots than in the shoots at the end of days 3 and 10. High transpiration caused more Pb uptake than did low transpiration. One volatile acid (propionic acid) and nine nonvolatile acids (lactic, glycolic, oxalic, succinic, fumaric, oxalacetic, d-tartaric, trans-aconitic, and citric acids) in rhizosphere quartz sand or anion-exchange resin were identified and quantified by gas chromatography analysis with a flame ionization detector. The amount of LMWOAs in rhizosphere quartz sand or anion-exchange resin increased with higher amounts of Pb in quartz sand solution and also with longer duration of the study. The total quantities of the LMWOAs in the rhizosphere quartz sand or anion-exchange resin were significantly higher under high and low transpiration with a 300 mg of Pb L (-1) solution addition at the end of day 10. Compared with our previous related studies (published work), the present study shows that the presence of LMWOAs in rhizosphere does not significantly affect Pb uptake by lettuce plants under high and low transpiration. A physiological mechanism of the roots of lettuce plants governing the relationship between Pb contamination level and quantity of water-soluble LMWOAs in rhizosphere quartz sand and resin, as influenced by transpiration, was proposed.


Assuntos
Ácidos Carboxílicos/análise , Lactuca/metabolismo , Chumbo/metabolismo , Transpiração Vegetal/fisiologia , Chumbo/administração & dosagem , Lactuca/crescimento & desenvolvimento , Nitratos/administração & dosagem , Raízes de Plantas/metabolismo , Solo/análise , Soluções
12.
J Air Waste Manag Assoc ; 57(2): 221-7, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17355083

RESUMO

The sites contaminated with recalcitrant polycyclic aromatic hydrocarbons (PAHs) are serious environmental problems ubiquitously. Some PAHs have proven to be carcinogenic and hazardous. Therefore, the innovative PAH in situ remediation technologies have to be developed instantaneously. Recently, the nanoscale zero-valent iron (ZVI) particles have been successfully applied for dechlorination of organic pollutants in water, yet little research has investigated for the soil remediation so far. The objective in this work was to take advantage of nanoscale ZVI particles to remove PAHs in soil. The experimental factors such as reaction time, particle diameter and iron dosage and surface area were considered and optimized. From the results, both microscale and nanoscale ZVI were capable to remove the target compound. The higher removal efficiencies of nanoscale ZVI particles were obtained because the specific surface areas were about several dozens larger than that of commercially microscale ZVI particles. The optimal parameters were observed as 0.2 g iron/2 mL water in 60 min and 150 rpm by nanoscale ZVI. Additionally, the results proved that nanoscale ZVI particles are a promising technology for soil remediation and are encouraged in the near future environmental applications. Additionally, the empirical equation developed for pyrene removal efficiency provided the good explanation of reaction behavior. Ultimately, the calculated values by this equation were in a good agreement with the experimental data.


Assuntos
Recuperação e Remediação Ambiental , Ferro/química , Pirenos/química , Poluentes do Solo/análise , Nanopartículas , Tamanho da Partícula , Pirenos/análise , Propriedades de Superfície , Taiwan
13.
J Air Waste Manag Assoc ; 55(8): 1200-7, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16187589

RESUMO

The sites contaminated with recalcitrant organic compounds, such as polycyclic aromatic hydrocarbons (PAHs) with multiple benzene rings, are colossal and ubiquitous environmental problems. They are relatively nonbiodegradable and mutagenic, and 16 of them are listed in the U.S. Environment Protection Agency priority pollutants. Thus, the efficient and emerging remediation technologies for removal of PAHs in contaminated sites have to be uncovered urgently. In this decade, the zero-valent iron (ZVI) particles have been used successfully in the laboratory, pilot, and field, such as degradation of chlorinated hydrocarbons and remediation of the other pollutants. Nevertheless, as far as we know, little research has investigated for soil remediation; this study used nanoscale ZVI particles to remove pyrene in the soil. The experimental variables were determined, including reaction time, iron particle size, and dosage. From the results, both the micro- and nanoscales of ZVI were capable of removing the target compound in soil, but the higher removal efficiencies were by nanoscale ZVI because of the massive specific surface area. The optimal operating conditions to attain the best removal efficiency of pyrene were obtained while adding nanoscale ZVI 0.1 g/g soil within 60 min and 150 rpm of mixing. Thus, nanoscale ZVI has proved to be a promising remedy for PAH-contaminated soil in this study, as well as an optimistically predictable application for additional pilot and field studies.


Assuntos
Ferro/química , Nanoestruturas/química , Pirenos/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Gerenciamento de Resíduos/métodos , Custos e Análise de Custo , Estudos de Viabilidade , Cinética , Microscopia Eletrônica de Varredura , Oxirredução , Tamanho da Partícula , Pirenos/química , Fatores de Tempo , Gerenciamento de Resíduos/economia
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