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1.
J Tradit Chin Med ; 44(1): 95-102, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38213244

RESUMO

OBJECTIVE: To elucidate the mechanism of the nourishing Yin and purging fire Chinese herbal mixture (NYPF) in delaying light-induced premature puberty in rats. METHODS: Twenty-one days old female Sprague-Dawley rats were randomly assigned to normal group (N), long light exposure group (L), NYPF and normal saline group (NS). Rats in the L, NYPF and NS groups were exposed to 16 h: 350 lux light/8 h: dark, while rats in the N group were exposed to 12 h: 50 lux light/12 h: dark. NYPF and normal saline was administered to the rats in the NYPF group or NS group, respectively, from day 21. Five rats in every group were sacrificed at 9 p.m. on day 28 (P28), on the day when rat's vulva opened in the L group (L-VO), on the day when the first estrous interphase occurred in rats of L group (L-E1), and on the day when the second estrous interphase occurred in rats of L group (L-E2), respectively. RESULITS: On day 34, all rats in the L group, 80% of rats in the NS group, 40% of rats in the N group, and 20% of rats in the NYPF group showed complete opening of the vulva. At P28, mRNA level of hypothalamic kisspeptin (Kiss-1) in the L group was significantly higher than that in the N group (P < 0.05). The rats in the L and NS groups had significantly lower hypothalamic arginine-phenylalanine-amide (RFamide)-related peptide 3 (RFRP-3) mRNA levels than those in the N group (P < 0.05), whereas RFRP-3 mRNA level was significantly higher in the NYPF group than that in the L group (P < 0.05). At L-VO, the ovarian index of the L and NS groups was significantly higher than that of the N group (P < 0.05) and estradiol (E2) level of the NYPF group was significantly lower than that of the N and NS groups (P < 0.05); hypothalamic Kiss-1 mRNA level in the L and NS groups was significantly higher than that in the N and NYPF groups (P < 0.05), whereas hypothalamic RFRP-3 mRNA level in the L, NYPF, and NS groups was significantly lower than that in the N group (P < 0.05). At L-E1, E2 level of the L and NS groups was significantly higher than that of the N group (P < 0.01), whereas it was significantly lower in the NYPF group than that of the N, L, and NS groups (P < 0.01), and serum luteinizing hormone level of the L and NS groups was significantly higher than that of the N group (P < 0.05); levels of serum melatonin and ovarian melatonin receptor 1 (MT-1) mRNA in the L, NYPF, and NS groups were significantly lower than those in the N group (P < 0.05). At L-E2, the uterine organ index of the NYPF group was significantly lower than that of the L group (P < 0.05); and ovarian MT-1 mRNA level of the L and NS groups was significantly lower than that in the N group (P < 0.05). CONCLUSIONS: NYPF can delay puberty onset in rats exposed to strong light for a prolonged duration, and regulation of the gene expression of Kiss-1 and RFRP-3 in the hypothalamus has been suggested as one of the mechanisms.


Assuntos
Kisspeptinas , Solução Salina , Ratos , Animais , Feminino , Ratos Sprague-Dawley , Kisspeptinas/metabolismo , Kisspeptinas/farmacologia , Solução Salina/metabolismo , Solução Salina/farmacologia , Maturidade Sexual , Hipotálamo/metabolismo , RNA Mensageiro/metabolismo
2.
Sci Rep ; 13(1): 21524, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057438

RESUMO

Shahe Reservoir is a key node in the upstream of the North Canal, and the water quality has gradually improved after the implementation of low water operation in 2018. The organic matter(OM) in the sediment decreased from 16.66 to 14.22%.In this study, the FI index and parallel factor method were used to investigate the traceability of OM and dissolved organic matter (DOM) in the Shahe Reservoir before and during low water level operation(LWLO), and the results showed that the terrestrial source fraction of OM in sediments was mainly related to organic-rich terrestrial plant residues carried by tributaries and overflows/outfalls during the rainy season, and the FI index indicated that the organic matter (OM) in the Shahe Reservoir before and during LWLO in each DOM in the area is derived from authigenic sources of autotrophic microorganisms, algae, etc. The parallel factor method shows that more than most of the pollutants in the DOM are input from endogenous sources and a small proportion of pollutants are input from exogenous sources. Nutrients in both sediment and interstitial water increased during the LWLO, with TN and TP levels increasing by 262.38 and 204.45 mg·kg-1 in sediment, NH4+-N, PO43--P, TN and TP in interstitial water increasing by 0.98, 1.36, 2.07 and 4.33 mg·L-1, respectively. Pearson correlation analysis and principal component analysis showed that OM was significantly correlated with nutrients: OM and TN (p < 0.01) and OM and TP (p < 0.05) in the pre-LWLO; OM and TN and TP (p < 0.01) in the LWLO.The results suggested that organic matter pollution control should be mainly carried out from the perspective of endogenous input, focusing on controlling the release of nutrients in sediments.

3.
BMC Immunol ; 23(1): 19, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35448938

RESUMO

BACKGROUND: 5-Fluorouracil (5-FU) is a used chemotherapy drug for cancer, and its main side effect is intestinal mucositis which causes chemotherapy to fail. It was known that short-chain fatty acids (SCFAs) can inhibit immune cell release of various proinflammatory factors and inhibit excessive intestinal inflammation. However, the inhibitory effect of SCFAs on 5-FU-induced intestinal mucositis is still unclear. RESULTS: To simulate the effects of SCFAs on immune and intestinal epithelial cells, the cells (THP-1 cells and Caco-2 cells) were pretreated with sodium acetate (NaAc), sodium propionate (NaPc) and sodium butyrate (NaB), then inflammation was induced by 5-FU. The expressions of reactive oxygen species (ROS), Beclin-1, LC3-II, NF-κB p65, NLRP3 inflammasome, proinflammatory/anti-inflammatory cytokines and mucosal tight junction proteins were determined. In our results, the three SCFAs could inhibit ROS expressions, NLRP3, Caspase-1, IL-1ß, IL-6, IL-18, Beclin-1 and LC3-II, when induced by 5-FU. In a 5-FU-induced chemoentermuctis mouse model, Lactobacillus rhamnoides can increase the concentrations of three SCFAs in faeces and increase the concentrations of IL-1ß, IL-6 and IgA in serum, and decrease the expressions of NLRP3 and IL-17 in spleen cells. The expressions of ZO-1 and Occludin in intestinal mucosa were significantly increased. CONCLUSIONS: These results indicated that the three SCFAs can effectively suppress the inflammation of THP-1 cells and Caco-2 cells and maintain tight junction integrity in intestinal mucosal epithelial cells.


Assuntos
Mucosite , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Proteína Beclina-1/metabolismo , Proteína Beclina-1/farmacologia , Células CACO-2 , Ácidos Graxos Voláteis/efeitos adversos , Ácidos Graxos Voláteis/metabolismo , Fluoruracila/efeitos adversos , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Interleucina-6/metabolismo , Mucosa Intestinal/metabolismo , Camundongos , Mucosite/induzido quimicamente , Mucosite/tratamento farmacológico , Mucosite/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Junções Íntimas/metabolismo
4.
Gynecol Endocrinol ; 38(4): 345-349, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35238278

RESUMO

OBJECTIVE: To observe and compare the expression of energy regulators (leptin/ghrelin) and PAI-1 in girls with abnormal uterine bleeding-ovulatory dysfunction (AUB-O) and healthy adolescent girls. METHODS: A total of 80 adolescent girls were studied including 60 with AUB-O and 20 healthy girls. All the general characteristics of subjects including height, weight, age, and age at menarche were collected after consent. The concentration of plasma leptin, ghrelin, PAI-1, and sex hormones was examined using enzyme-linked immunosorbent assay (ELISA) and DXI800 Access immunoassay system respectively. RESULTS: Two groups were comparable in the age at menarche, visiting age, postmenarchal years, and BMI SDS (p > .05). Levels of leptin (11.12 ± 4.96 ng/ml vs. 18.59 ± 13.22 ng/ml, p < .001) and PAI-1 (116.40 ± 36.63 ng/ml vs. 173.19 ± 52.44 ng/ml, p < .001) in girls with AUB-O were significantly lower than that in healthy girls, and the levels of ghrelin were significantly higher than that in healthy girls (1.52 ± 4.20 ng/ml vs. 0.43 ± 0.64 ng/ml, p = .01). At the same time, we also found that girls with AUB-O showed negative correlation between the level of leptin, ghrelin, and estradiol. CONCLUSIONS: Energy metabolism and coagulation might play a role in the development of AUB-O in adolescent girls.


Assuntos
Leptina/sangue , Inibidor 1 de Ativador de Plasminogênio/sangue , Adolescente , Estatura , Feminino , Grelina , Humanos , Hemorragia Uterina
5.
Microb Pathog ; 156: 104827, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33892129

RESUMO

Despite advancements in diagnosis and control, Aeromonas infections are considered the leading cause of economic aquaculture loss. In this study, to enhance DNA vaccine efficacy against Aeromonas infections, a fused DNA fragment (1504 bp) of the OmpAI gene from Aeromonas veronii (A. veronii) combined with the C5-I gene from the common carp was generated with splicing by overlapping PCR (SOE-PCR) and expressed in Lactobacillus casei strain CC16. Protein C5-I served as a molecular adjuvant for the antigen OmpAI. Two types of fusion antigens were developed (anchored and secretory). Generally, anchored-type antigens are more effective in inducing immune responses in fish than secretory antigens. Western blot analysis showed that the bands of both antigens were present at 58 kDa. After oral immunization, both DNA vaccines enhanced the serum levels of AKP, ACP, SOD and LZM in immunized carp; the genes IL-10, IL-1ß, TNF-α, and IFN-γ in the heart, liver, spleen, head kidney, and intestinal tract were upregulated; and a stronger phagocytic response was triggered in immunized fish. In addition, common carp administered the fused antigens were more protected from Aeromonas challenge (60-73.3% protection). Recombinant Lactobacillus bacteria expressing the fused protein showed a greater propensity for colonization in the intestinal tract in immunized fish than in controls. Here, we provide a promising approach to improve DNA vaccine immunogenicity for protecting common carp from A. veronii infections.


Assuntos
Carpas , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Lacticaseibacillus casei , Aeromonas veronii/genética , Animais , Vacinas Bacterianas/genética , Doenças dos Peixes/prevenção & controle , Infecções por Bactérias Gram-Negativas/prevenção & controle , Infecções por Bactérias Gram-Negativas/veterinária , Lacticaseibacillus casei/genética
6.
Biomed Res Int ; 2018: 9153496, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29750173

RESUMO

INTRODUCTION: All adult medulloblastoma (AMB) patients should be treated with craniospinal irradiation (CSI) postoperatively. Because of the long irradiation range, multiple radiation fields must be designed for conventional radiotherapy technology. CSI can be completed in only one session with helical tomotherapy (HT). We evaluated the dose of HT, volumetric intensity modulated arc therapy (VMAT), and three-dimensional conformal radiotherapy (3D-CRT) of AMB and the results of 5 cases of AMB treated with HT. METHODS: Complete craniospinal and posterior cranial fossa irradiation with HT, VMAT, and 3D-CRT and dose evaluation were performed. And results of 5 cases of AMB treated with HT were evaluated. RESULTS: A large volume of tissue was exposed to low dose radiation in the organs at risk (OAR), while a small volume was exposed to high dose radiation with HT. The conformity and uniformity of the targets were good with HT and VMAT, and the volume of targets exposed to high dose with VMAT was larger than that of HT. The uniformity of 3D-CRT was also good, but the dose conformity was poor. The main toxicity was hematologic toxicity, without 4th-degree bone marrow suppression. There was 3rd-degree inhibition in the white blood cells, hemoglobin, and platelets. The three female patients suffered menstrual disorders during the course of radiation. Two female patients with heavy menstruation suffered 3rd-degree anemia inhibition, and 2 patients suffered amenorrhea after radiotherapy. Although menstrual cycle was normal, the third patient was not pregnant. CONCLUSION: CSI with HT is convenient for clinical practice, and the side effects are mild. With good conformity and uniformity, VMAT can also be used for selection in CSI. For poor conformity, 3D-CRT should not be the priority selection for CSI. In female patients, the ovaries should be protected.


Assuntos
Neoplasias Cerebelares/radioterapia , Meduloblastoma/radioterapia , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/métodos , Adolescente , Adulto , Feminino , Humanos , Masculino , Órgãos em Risco/efeitos da radiação , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Estudos Retrospectivos , Adulto Jovem
7.
Sci Rep ; 8(1): 5595, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618828

RESUMO

This study is to analyze the radiation dose of head, body and tail of hippocampus (HC) of nasopharyngeal carcinoma (NPC) patients treated with intensity modulated radiotherapy (IMRT). Evaluate cognitive function of patients with Wechsler adult intelligence scale-Chinese revised (WAIS-CR). HC were segmented into HC head (HH), HC body (HB) and HC tail (HT) and the indexes were then analyzed. WAIS-CR was tested before and 3months after radiotherapy. The mean radiation dose of left and right HC was (1147 ± 976)cGy, (1011 ± 602)cGy respectively. The radiation dose and the volume exposed in different dose of HH, HB and HT decreased in turn. For 5 patients, before and after radiotherapy, the regular-order score was 8.60 ± 1.34, 8.0 ± 1.00 (P = 0.43), while the reverse-order score was 5.80 ± 0.84, 5.20 ± 0.84 (P = 0.07). The radiation dose of HH, HB and HT was different, and the radiation dose of HH was the highest, which should be emphasized especially.


Assuntos
Hipocampo/efeitos da radiação , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Adulto , Antineoplásicos/uso terapêutico , Feminino , Raios gama , Hipocampo/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/mortalidade , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , Doses de Radiação , Radioterapia de Intensidade Modulada , Taxa de Sobrevida , Adulto Jovem
8.
Sci Rep ; 7(1): 13643, 2017 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-29057892

RESUMO

The structural and photophysical characteristics of MAPbBr3 single crystals prepared using the inverse temperature crystallization method are evaluated using temperature-dependent X-ray diffraction (XRD) and optical spectroscopy. Contrary to previous research reports on perovskite materials, we study phase transitions in crystal lattice structures accompanied with changes in optical properties expand throughout a wide temperature range of 300-1.5 K. The XRD studies reveal several phase transitions occurred at ~210 K, ~145 K, and ~80 K, respectively. The coexistence of two different crystallographic phases was observed at a temperature below 145 K. The emission peaks in the PL spectra are all asymmetric in line shape with weak and broad shoulders near the absorption edges, which are attributed to the Br atom vacancy on the surface of the crystals. The time-resolved PL measurements reveal the effect of the desorption/adsorption of gas molecules on the crystal surface on the PL lifetimes. Raman spectroscopy results indicate the strong interplays between cations and different halide atoms. Lastly, no diamagnetic shift or split in emission peaks can be observed in the magneto-PL spectra even at an applied magnetic field up to 5 T and at a temperature as low as 1.5 K.

9.
Int J Pharm ; 500(1-2): 54-61, 2016 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-26748365

RESUMO

A liver-targeted drug delivery system (CX-EPNP) composed of PLGA/TPGS was prepared and characterized. The surface of nanoparticle was conjugated with LFC131 peptide to increase the specific interaction of carrier with CXCR4 overexpressing liver cancers to enhance the Epirubicin (EPI) delivery to tumors. The particles were nanosized with size than 150 nm and portrayed a sustained release kinetics suggesting its suitability for cancer targeting. The in vitro cell uptake results showed that the introduction of LFC131 to the nanoparticles could increase significantly the affinity to human hepatic carcinoma cells (HepG2) with approximately a 3-fold improvement in cellular uptake than non-targeted one. A specific receptor-mediated uptake was observed by confocal laser scanning microscopy. In addition, CX-EPNP showed remarkable cytotoxicity towards HepG2 cells, and could effectively inhibit tumor growth. The more significant EPI accumulation from CX-EPNP in the cancer cells gave rise to the enhanced EPI cytotoxicity and cell apoptosis. The CX-EPNP distributed mostly in the xenograft tumor after intravenous administration to mice and adequately remained in the blood for at least 24h. It seemed that CX-EPNP upon intravenous injection avoided rapid recognition by Kupffer cells and adequately remained in the blood. These findings suggest that CX-EPNP could effectively inhibit the growth of liver tumors in situ and could potentially reduce the systemic side effects. However, extensive investigation is still needed to assess the possible applications of the CX-EPNP in humans.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Epirubicina/administração & dosagem , Nanopartículas/administração & dosagem , Animais , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Epirubicina/química , Epirubicina/farmacologia , Epirubicina/uso terapêutico , Células Hep G2 , Humanos , Ácido Láctico/química , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Camundongos , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Nanopartículas/uso terapêutico , Nanopartículas/ultraestrutura , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Resultado do Tratamento , Vitamina E/química
10.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 28(6): 732-734, 2016 Nov 15.
Artigo em Chinês | MEDLINE | ID: mdl-29469278

RESUMO

OBJECTIVE: To evaluate the effect of health education on schistosomiasis in Kunshan City, so as to provide the evidence for making the consolidating strategy in the late stage of interruption of schistosomiasis transmission. METHODS: The residents, middle school students and elementary school students were randomly sampled from one community, one middle school and one elementary school of each of two towns and they were investigated with interviews and questionnaires for the implementation of health education on schistosomiasis prevention and control. RESULTS: A total of 452 middle school students (232 cases) and primary school students (220 cases) were surveyed. The awareness rate of total schistosomiasis knowledge was 98.21% among the students (the awareness rate of basic schistosomiasis knowledge was 98.42% and the awareness rate of preventive schistosomiasis knowledge was 98.01%). Among the 220 elementary school students, the awareness rate of total schistosomiasis knowledge was 97.21% (the awareness rate of basic schistosomiasis knowledge was 97.60% and the awareness rate of preventive schistosomiasis knowledge was 96.82%). Among the 232 middle school students, the awareness rate of total schistosomiasis knowledge was 99.17% (χ2 = 34.661, compared with the rate of the elementary school students) [the awareness rate of basic schistosomiasis knowledge was 99.20% (χ2 = 13.045, compared with the rate of the elementary school students) and the awareness rate of preventive schistosomiasis knowledge was 99.14% (χ2 = 21.796, compared with the rate of the elementary school students)]. There were significant differences between the elementary school students and middle school students in above-mentioned awareness rates (all P < 0.001). There were schistosomiasis health education materials or teaching plans in all the four schools. Among the 402 residents surveyed, the awareness rate of total schistosomiasis knowledge was 98.87%. CONCLUSIONS: The effect of health education on schistosomiasis prevention and control is very well, and the total awareness rate of schistosomiasis prevention and control knowledge among the population has reached the goal (more than 95%) of the medium- and long-term planning of schistosomiasis prevention and control in Kunshan City.


Assuntos
Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Esquistossomose/prevenção & controle , China , Humanos , Instituições Acadêmicas , Estudantes , Inquéritos e Questionários
11.
Water Res ; 47(11): 3591-9, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23726695

RESUMO

In this paper, endotoxin contamination was determined in treated water following each unit of a drinking water treatment plant (WTP) in Beijing, China and its source water (SW) from a long water diversion channel (Shijiazhuang-Beijing) originating from four reservoirs in Hebei province, China. The total-endotoxin activities in SW ranged from 21 to 41 EU/ml at five selected cross sections of the diversion channel. The total-endotoxin in raw water of the WTP ranged from 11 to 16 EU/ml due to dilution and pretreatment during water transportation from Tuancheng Lake to the WTP, and finished water of the WTP ranged from 4 to 10 EU/ml, showing a 49% decrease following the full-scale treatment process at the WTP. Compared with the 31% removal of free-endotoxin, the WTP removed up to 71% of bound-endotoxin in raw water. The traditional treatment processes (coagulation, sedimentation and filtration) in the WTP removed substantial amounts of total-endotoxin (up to 63%), while endotoxin activities increased after granular activated carbon (GAC) adsorption and chlorination. The total-endotoxin in the actual water was composed of free-endotoxin and bound-endotoxin (endotoxin aggregates, bacteria-bound endotoxins and particle-attached endotoxins). The endotoxin aggregates, bacteria-bound endotoxins and particle-attached endotoxins co-exist as suspended particles in water, and only the bacteria-bound endotoxins were correlated with bacterial cells suspended in water. The particle distribution of endotoxin aggregates in ultrapure water was also tested and the results showed that the majority (64-89%) of endotoxin aggregates had diameters <2 µm. The endotoxin contamination and control in treated water following each unit of the WTP processes and its SW from reservoirs are discussed and compared with regard to bacterial cell counts and particle characteristics, which were dependent, to a certain extent, on different flow rates and turbulence of the water environments.


Assuntos
Água Potável/química , Endotoxinas/análise , Água Doce/microbiologia , Poluição da Água/análise , Purificação da Água/métodos , Adsorção , China , Água Potável/análise , Água Potável/microbiologia , Filtração , Água Doce/química
12.
Clin Imaging ; 34(5): 351-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20813298

RESUMO

AIM: To evaluate magnetic resonance (MR) imaging of pancreatic metastases secondary to primary lung cancers. MATERIALS AND METHODS: Eleven cases included T1-weighted, T2-weighted, and spectral presaturation attenuated inversion recovery T2-weighted images. RESULTS: Of the 21 total pancreatic lesions evaluated, 10 exhibited a peripheral rim of high signal intensity, 9 displayed a homogeneous signal intensity, and 2 lesions demonstrated a heterogeneous pattern of contrast enhancement. CONCLUSION: Limitations in evaluating pancreatic metastases by MR imaging require definitive diagnoses to rely on both clinical data and MR imaging.


Assuntos
Neoplasias Pulmonares/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/secundário , Adulto , Idoso , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Meglumina/análogos & derivados , Pessoa de Meia-Idade , Compostos Organometálicos , Pâncreas/patologia , Reprodutibilidade dos Testes , Estudos Retrospectivos
13.
Anal Sci ; 26(1): 39-44, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20065585

RESUMO

The electrochemical activities of PbO(2) thin-film electrodes were systematically studied with an oxygen-transfer reaction, i.e., the oxidation of thiourea. Five different types of PbO(2) film electrodes were prepared using various methods to investigate the influence of the interfacial oxide layer formed between the Ti substrate and the PbO(2) layer contacting the electrolyte. Among the electrodes tested, PbO(2) electrode prepared by minimizing the formation of the interfacial oxide by either the electrochemical or thermal decomposition method generally exhibited better electrochemical activity. From the results, it can be inferred that the enhanced electrochemical activity of the electrode is due to minimization of the interfacial resistance by the introduction of a metallic Pb layer between the Ti substrate and the PbO(2) layer, and to an increase in the roughness on the surface of the PbO(2) layer.

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