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1.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(2): 152-157, 2019 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30975280

RESUMO

Objective To investigate the effect of PM2.5 on the distribution and expression of occludin in nasal mucosal epithelial cells. Methods The normal human nasal epithelial cell line HNEpCs were stimulated with PM2.5 in vitro. The incubated cells were treated with 0, 50, 100, 200, 400, 500, 800, 1000 µg/mL of PM2.5. The suitable concentration of PM2.5 was determined according to the cell viability measured by CCK-8 assay. Then the incubated cells were treated with 200, 400, 500 µg/mL of PM2.5. The occludin expression and distribution on the levels of protein and mRNA were detected by immunofluorescence assay, Western blot analysis and real-time fluorescence quantitative PCR. Results Compared with the control group, the cell viability of HNEpCs treated with different concentrations of PM2.5 decreased after 24 and 48 hours. The cell viability was negatively correlated with PM2.5 concentrations. Compared with the control group, there was no obvious change in the cell morphology and occluding expression of the 200 µg/mL PM2.5 group. The cell morphology changed into the spindle shape in the 400 µg/mL group, and a small number of vacuoles appeared in the cell connection. After treated with 500 µg/mL PM2.5, the cell density decreased, normal cell morphology changed into irregular long spindle shape and the intercellular space was enlarged. Occludin mRNA and protein levels were down-regulated in all the groups except for the cells treated with 200 g/mL PM2.5 for 24 hours, and occludin protein expression levels were time-dependent. Conclusion PM2.5 can reduce the viability of HNEpCs in normal human nasal epithelial cell line, and reduce the mRNA and protein expression of the intercellular occludin.


Assuntos
Células Epiteliais , Expressão Gênica , Mucosa Nasal , Ocludina , Material Particulado , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Mucosa Nasal/citologia , Mucosa Nasal/metabolismo , Ocludina/genética , Material Particulado/toxicidade
2.
Food Chem ; 284: 73-79, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30744870

RESUMO

The dissipation kinetics of a combined use of procymidone and thiamethoxam, and their impact on the biodiversity and pathogen on surface of tomatoes were studied. The half-lives of procymidone and thiamethoxam, used either on their own or in combination with each other, were 2.94 or 3.26 days and 2.41 or 2.67 days, respectively. The residues dropped below the maximum residue limit (MRL) after 7 or 10 days (MRL 2 mg·kg-1 for procymidone), and 10 or 14 days (MRL 0.2 mg·kg-1 for thiamethoxam), respectively. The phylum Bacteroidetes, Cyanobacteria, and Proteobacteria, were dominantly present in all studied samples. The genus Escherichia-Shigella was found and exposed to the dissipation of procymidone (r = -0.9209 for procymidone on its own, and r = -0.8611 for procymidone in combination with thiamethoxam). These results will contribute to establish adequate monitoring of pesticides residues and their incorporation in surface ecology and pathogen management strategies in tomatoes.


Assuntos
Biodiversidade , Compostos Bicíclicos com Pontes/administração & dosagem , Fungicidas Industriais/administração & dosagem , Inseticidas/administração & dosagem , Lycopersicon esculentum/microbiologia , Tiametoxam/administração & dosagem , Bactérias/isolamento & purificação , Lycopersicon esculentum/química , Resíduos de Praguicidas/análise , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle
3.
J BUON ; 23(4): 1041-1048, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30358209

RESUMO

PURPOSE: To investigate the characteristics of lymph node (LN) metastasis of papillary thyroid carcinoma (PTC) with ultrasonography (US) and spiral computed tomography (CT) and the significance of their combination in the diagnosis and prognosis of LN metastasis. METHODS: A total of 93 PTC patients admitted to and treated in the oncology department of our hospital were randomly enrolled in this study. LN imaging signs were explored by US, CT and their combination. Through the comparison with pathological findings, the diagnostic efficiency of three methods in LN metastasis in patients with PTC was analyzed. Postoperatively, all patients were followed up for 1-3 years to analyze the relationship between LN metastasis and the prognosis of PTC. RESULTS: Among 93 PTC patients, 69 (74.19%) had LN metastasis, and 24 (25.81%) had not. US examination revealed that metastatic LN were hypoechoic and obviously calcified, and had aspect ratio >1 and strong blood flow signals. Among them, there were significant differences in calcification and blood flow between LN metastasis group and non-metastasis group (p<0.05). CT images indicated that metastatic LN were swollen, had low-density and were calcified with abundant blood flow signals. In addition, the edge, calcification and CT reinforced examination showed obvious differences between the LN metastasis group and the non-metastasis group (p<0.05). The sensitivity, specificity and accuracy of US alone in the diagnosis of LN metastasis were clearly better than those of CT alone (p<0.05), while their combination was better than both US and CT alone in the sensitivity, specificity and accuracy in the diagnosis of LN metastasis (p<0.05). Follow-up data suggested that the 3-year recurrence or metastasis rates of patients in the metastasis and non-metastasis groups were 4.54 and 11.27%, respectively, showing a statistically significant difference (p<0.05). CONCLUSIONS: US combined with CT can make up for the deficiencies of each examination alone, and improve the sensitivity and specificity of PTC LN metastasis detection. It is worthy of clinical promotion.


Assuntos
Linfonodos/diagnóstico por imagem , Câncer Papilífero da Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Humanos , Linfonodos/patologia , Metástase Linfática , Imagem Multimodal/métodos , Prognóstico , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos
4.
Exp Ther Med ; 16(2): 1009-1013, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30116352

RESUMO

Azithromycin has been widely used for the treatment of Treponema pallidum. However, the drug resistance of T. pallidum for azithromycin is currently increasing. The aim of the present study was to analyze the association between gene subtypes of T. pallidum and drug resistance for azithromycin. The gene subtypes of T. pallidum were assayed by a polymerase chain reaction technique. Drug resistance of T. pallidum was analyzed using an antimicrobial susceptibility test. The results demonstrated that gene type tpr presented higher drug resistance compared with arp and tp0548 gene types of T. pallidum. Gene type tpr was identified as eight gene subtypes (14a/f, 14e/f, 12e/f, 12d/f, 6d/f, 11d/f, 14j/f and 8d/f) among 324 cases. It was identified that 23S rRNA A2058G mutation was observed in gene subtypes 14a/f, 14e/f and 12e/f. A2059G mutation occurred in the gene subtypes 8d/f, 12d/f, 6d/f, 11d/f and 14j/f. The proportions of azithromycin-resistant genotypes harboring either the A2058G or the A2059G mutation among the T. pallidum strains were 34.2 and 65.8%, respectively. The antimicrobial susceptibility test demonstrated that A2059G mutations exhibited a higher drug resistance for azithromycin compared with A2058G mutations. In conclusion, these results indicate that azithromycin resistance in T. pallidum is associated with gene subtype, which may contribute to the treatment of T. pallidum.

5.
Prenat Diagn ; 38(11): 829-834, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30035813

RESUMO

OBJECTIVES: The objective of the study is to evaluate the diagnostic value of ultrasonography in cystic lesions of the adrenal gland. METHODS: Twenty-two cases of adrenal cystic lesions found in the foetal period were retrospectively analysed. All foetuses were followed up by ultrasound after birth, and all lesions were confirmed by operation or ultrasound-guided biopsy. RESULTS: Sixteen foetuses displayed anechoic findings, and 6 had patchy mixed echoic findings. Nevertheless, the characteristics of these lesions changed in the neonatal period: 7 cases presented as anechoic and 15 cases presented as mixed echoic. The final pathology revealed simple cysts in 7 cases, intracystic haemorrhage in 9 cases, and 6 cases of spontaneous haemorrhage of the adrenal glands. CONCLUSIONS: The ultrasonographic findings of foetal cystic lesions in the adrenal gland and the change they undergo after birth may provide valuable information for clinical diagnosis.


Assuntos
Doenças das Glândulas Suprarrenais/diagnóstico por imagem , Cistos/diagnóstico por imagem , Doenças Fetais/diagnóstico por imagem , Ultrassonografia Pré-Natal , Feminino , Humanos , Gravidez , Estudos Retrospectivos
6.
Acta Crystallogr C Struct Chem ; 74(Pt 2): 171-176, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29400332

RESUMO

A dimerized 1,3-diazaazulene derivative, namely 1,4-bis(1,3-diazaazulen-2-yl)benzene [or 2,2'-(1,4-phenylene)bis(1,3-diazaazulene)], C22H14N4, (I), has been synthesized successfully through the condensation reaction between 2-methoxytropone and benzene-1,4-dicarboximidamide hydrochloride, and was characterized by 1H NMR and 13C NMR spectroscopies, and ESI-MS. X-ray diffraction analysis reveals that (I) has a nearly planar structure with good π-electron delocalization, indicating that it might serve as a π building block. The crystal belongs to the monoclinic system. One-dimensional chains were formed along the a axis through π-π interactions and adjacent chains are stabilized by C-H...N interactions, forming a three-dimensional architecture. The solid emission of (I) in the crystalline form exhibited a 170 nm red shift compared with that in the solution state. The observed optical bandgap for (I) is 3.22 eV and a cyclic voltammetry experiment confirmed the energy levels of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). The calculated bandgap for (I) is 3.37 eV, which is very close to the experimental result. In addition, the polarizability and hyperpolarizability of (I) were appraised for its further application in second-order nonlinear optical materials.

7.
Int J Cardiovasc Imaging ; 34(3): 379-384, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28936576

RESUMO

Three-dimensional speckle tracking echocardiography (3D-STE) was used to evaluate the improvement of continuous subcutaneous insulin infusion on the left ventricular (LV) systolic function of patients with type 2 diabetes mellitu (T2DM). We recruited T2DM patients (38 cases, diabetic group) and healthy volunteers (35 cases, control group) to collect LV full volume imaging. TomTec software was used for calculating LV global longitudinal strain (LVGLS), global circumferential strain (LVGCS), peak twist (LVTW), peak apical rotation (LVPAR), ejection fraction (LVEF), and torsion (LVT). All indices were re-tested 2 weeks later after intensive treatment of insulin pump. LVGLS, LVGCS, LVTW and LVPAR in diabetic group were significantly decreased than control group. LVGLS and LVGCS in pre-treatment diabetic group were significantly increased than post-treatment. LVGLS, LVGCS, LVTW and LVPAR had correlations among control, pre-treatment and post-treatment diabetic groups. There were no significant differences in LVEDV, LVESV, LVEF, LVT and R-R. LV systolic function of patients with T2DM complicated with microangiopathy was improved after treatment of continuous subcutaneous insulin infusion. In addition, therapeutic effect could be accurately evaluated by 3D-STE which had vital clinical application.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Ecocardiografia Tridimensional , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda , Adulto , Idoso , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Humanos , Infusões Subcutâneas , Sistemas de Infusão de Insulina , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Recuperação de Função Fisiológica , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologia
8.
J Food Sci ; 82(3): 787-793, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28135399

RESUMO

Purple sweet potato (PSP) is widely grown in Asia and considered as a healthy vegetable. The objective of the current study was to determine the anti-obesity effect of the PSP on high fat diet induced obese C57BL/6J mice. The mice were administrated with high fat diet supplemented with the sweet potato (SP) or PSP at the concentration of 15% and 30% for 12 wk, respectively. The results showed that the supplementation of SP or PSP at 30% significantly ameliorated high fat diet induced obesity and its associated risk factors, including reduction of body weight and fat accumulation, improvement of lipid profile and modulation of energy expenditure. Moreover, PSP also posed beneficial effect on the liver and kidney functions. These results indicate that PSP and SP have anti-obesity effect and are effective to reduce the metabolic risk.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Ipomoea batatas/química , Obesidade/dietoterapia , Tubérculos , Ganho de Peso , Tecido Adiposo/metabolismo , Animais , Antocianinas/farmacologia , Antocianinas/uso terapêutico , Ásia , Peso Corporal/efeitos dos fármacos , Fibras na Dieta/farmacologia , Fibras na Dieta/uso terapêutico , Metabolismo Energético/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/metabolismo , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/sangue , Obesidade/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
9.
PLoS One ; 11(10): e0164771, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27768776

RESUMO

Hepcidin, one kind of antimicrobial peptides, is one of the promising alternatives to antibiotics with broad spectrum of antimicrobial activity. Hepcidins cloned from different kinds of fishes have been produced using exogenous expression systems, and their in vitro antimicrobial effects have been verified. However their in vivo effects on gut microbiota and gut health of hosts remain unclear. Here we performed a safety study of hepcidin so that it can be used to reduce microbial contaminations in the food and feed. In this study, Pichia pastoris-expressed Pseudosciaena crocea hepcidin (PC-hepc) was first assessed by simulated digestion tests and then administered to male and female Sprague-Dawley (SD) rats in different concentrations. Subchronic toxicity testing, high throughput 16S rRNA sequencing of gut microbiota, and examinations on gut metabolism and permeability were conducted. The results showed PC-hepc could be digested in simulated intestinal fluid but not in simulated gastric fluid. PC-hepc had no adverse effects on general health, except causing increase of blood glucose (still in the normal value range of this index) in all trial groups of female rats and intestinal inflammation in HD group of female rats. Community composition of gut microbiota of female MD and HD groups shifted compared with control group, of which the decrease of genus Akkermansia might be related to the increase of blood glucose and intestinal inflammation. Significant increase of fecal nitroreductase activity was also observed in female MD and HD groups. Our results suggest the uses of exogenous PC-hepc in normal dosage are safe, however excess dosage of it may cause intestinal disorder of animals.


Assuntos
Anti-Infecciosos/farmacologia , Hepcidinas/genética , Intestinos/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Pichia/genética , Animais , Glicemia/metabolismo , Fezes/enzimologia , Feminino , Intestinos/microbiologia , Masculino , Nitrorredutases/metabolismo , Ratos
10.
Shanghai Kou Qiang Yi Xue ; 25(5): 609-612, 2016 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-28116437

RESUMO

PURPOSE: To evaluate the effect of fluoride removal agent and microabrasion technology in LED teeth whitening of dental fluorosis. METHODS: One hundred and twelve patients with moderate dental fluorosis treated from August 2012 to July 2015 were divided into experimental group and control group according to random number table, with 61 cases in each group. In addition to pretreatment for all patients, patients in the control group were given combined treatment of Beyond LED whitening and fluoride removal agent; while patients in the experimental group were given microabrasion before LED whitening, with the same subsequent treatment process as that in the control group. The whitening effect and tooth sensitivity during whitening were compared between the two groups at the completion of treatment, 1 month and 6 months after treatment. SPSS 19.0 software package was employed for statistical analysis. RESULTS: There were no ineffective or lost patients in 2 groups. The effective rate of whitening for patients in the experimental group at completion of treatment, 1 month and 6 months after treatment was significantly higher than that in the control group (P<0.05). There was no case with tooth sensitivity during treatment. There was no significant difference in non-significant sensitivity rate or significant sensitivity rate between the 2 groups (P>0.05). CONCLUSIONS: Combined treatment with fluoride removal agent and microabrasion technology in LED teeth whitening for dental fluorosis can significantly improve the whitening effect and will not interfered by significantly increased tooth sensitivity.


Assuntos
Luzes de Cura Dentária , Fluorose Dentária/terapia , Clareamento Dental/métodos , Sensibilidade da Dentina , Fluoretos , Humanos , Fosfatos
11.
Artigo em Chinês | MEDLINE | ID: mdl-25997269

RESUMO

Total hip replacement (THR) is replacing the prosthesis stem similar to human bone that takes advantage of the material with both good mechanical properties and biocompatibility to the damaged articular surface. Thus it can not only alleviate or even eliminate the pain but also effectively maintain the joint stability and freedom and restore its normal performance. Finite element analysis was used in this study to establish a 3D model of artificial hip stem, and explore its fatigue properties of different materials to ensure the safety and reliability. The calculating obtained two results of different metal hip prosthesis, including lifetime and deformation. The minimum service life of titanium prosthesis reaches 568 million times, which satisfies ISO standards, while the stainless steel does not suit to be a prosthesis material.


Assuntos
Prótese de Quadril , Teste de Materiais , Falha de Prótese , Artroplastia de Quadril , Análise de Elementos Finitos , Articulação do Quadril , Humanos , Modelos Anatômicos , Reprodutibilidade dos Testes , Aço Inoxidável , Titânio
12.
Chem Commun (Camb) ; 51(42): 8765-8, 2015 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-25913500

RESUMO

A nanometer-thick linear graphene edge nanoelectrode was constructed based on the edge plane of chemical vapor deposition (CVD) grown few-layer graphene, which showed much better electrochemical performance compared with traditional carbon fibre microelectrodes.

13.
Angew Chem Int Ed Engl ; 54(16): 4870-5, 2015 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-25728521

RESUMO

Water oxidation is the key step in natural and artificial photosynthesis for solar-energy conversion. As this process is thermodynamically unfavorable and is challenging from a kinetic point of view, the development of highly efficient catalysts with low energy cost is a subject of fundamental significance. Herein, we report on iron-based films as highly efficient water-oxidation catalysts. The films can be quickly deposited onto electrodes from Fe(II) ions in acetate buffer at pH 7.0 by simple cyclic voltammetry. The extremely low iron loading on the electrodes is critical for improved atom efficiency for catalysis. Our results showed that this film could catalyze water oxidation in neutral phosphate solution with a turnover frequency (TOF) of 756 h(-1) at an applied overpotential of 530 mV. The significance of this approach includes the use of earth-abundant iron, the fast and simple method for catalyst preparation, the low catalyst loading, and the large TOF for O2 evolution in neutral aqueous media.

14.
Ying Yong Sheng Tai Xue Bao ; 26(10): 3103-10, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26995919

RESUMO

Considering the characteristics of rice production and climate conditions in Southwest China, an agricultural drought monitoring model based on wetness index anomaly rate (Mp) by calculating the variation of deviation from average values of relative humid index was established, and was used to analyze the spatial-temporal distribution characteristics of the rice drought during the growth season in Southwest China in the past 50 years (1961-2010). The applicability of the Mp model in Southwest China was verified by using this model to monitor the rice drought. The result showed there was a decreasing trend in the frequency of rice drought in term of the decadal variability. The areas with high drought risk mainly concentrated in northwestern and mid-eastern Yunnan Province, eastern Sichuan Basin, northeastern Chongqing City, and southeastern Guizhou Province. The drought frequency was highest at the stage from transplanting to tasseling, followed by the stage from grain filling to maturity, and was lowest at the stage from tasseling to grain filling. Mp was suitable for monitoring the rice drought in Southwest China, and could be used as a reference for the rice planting areas without irrigation data.


Assuntos
Agricultura , Secas , Oryza/crescimento & desenvolvimento , China , Mudança Climática , Ecossistema , Modelos Teóricos , Análise Espaço-Temporal
15.
Nanoscale ; 6(5): 2768-75, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24463536

RESUMO

A one-pot solvothermal process has been developed for direct preparation of PdCu nanocapsules (with a size of ca. 10 nm) on three-dimensional (3D) graphene. Due to the 3D pore-rich network of graphene and the unique hollow structure of PdCu nanocapsules with a wall thickness of ca. 3 nm, the newly-prepared PdCu/3D graphene hybrids activated electrochemically have great electrocatalytic activity towards ethanol oxidation in alkaline media, much better than single-phase Pd and commercial E-TEK 20% Pt/C catalysts promising for application in direct ethanol fuel cells.


Assuntos
Etanol/química , Grafite/química , Nanocápsulas/química , Catálise , Cobre/química , Técnicas Eletroquímicas , Eletrodos , Oxirredução , Tamanho da Partícula , Platina/química
16.
J Fluoresc ; 24(1): 189-95, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23974700

RESUMO

A new daunorubicin has been synthesized and structurally characterized. The interaction of native calf thymus DNA (ctDNA) with 3'-azido-daunorubicin thiosemicarbazone (ADNRT) was investigated under simulated physiological conditions by multi-spectroscopic techniques, viscometric measurements and molecular modeling study. It concluded that ADNRT could intercalate into the base pairs of ctDNA, and the fluorescence quenching by ctDNA was static quenching type. Thermodynamic parameters calculated suggested that the binding of ADNRT to ctDNA was mainly driven by hydrophobic interactions. The relative viscosity of ctDNA increased with the addition of ADNRT, which confirmed the intercalation mode. Furthermore, molecular modeling studies corroborate the above experimental results.


Assuntos
DNA/química , Daunorrubicina/análogos & derivados , Tiossemicarbazonas/química , Animais , Bovinos , Daunorrubicina/química , Modelos Moleculares , Espectrometria de Fluorescência , Viscosidade
17.
J Agric Food Chem ; 58(15): 8490-4, 2010 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-20614904

RESUMO

As more and more genetically modified organisms (GMO) are commercialized, efficient and inexpensive assays are required for their quick detection. An event-specific detection strategy based on the unique and specific sequences of integration junctions is useful because of its high specificity. This study developed a system for detecting six GM maize lines (Bt11, Bt176, GA21, MON810, NK603, and T25) using optical silicon thin-film biosensor chips. Aldehyde-labeled probes were arrayed and covalently attached to a hydrazine-derivatized chip surface. Biotinylated PCR amplicons were then hybridized with the probes. After washing and brief incubation with an anti-biotin IgG horseradish peroxidase conjugate and a precipitable horseradish peroxidase substrate, biotinylated PCR amplicons perfectly matched with the probes can be visualized by the color change on the chip surface (gold to blue/purple). This assay is extremely robust, exhibits high sensitivity and specificity, and is flexible from low through moderate to high throughput.


Assuntos
Técnicas Biossensoriais/métodos , Plantas Geneticamente Modificadas/genética , Zea mays/genética , Técnicas Biossensoriais/instrumentação
18.
Bioelectrochemistry ; 74(2): 232-5, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19028443

RESUMO

In pH 5.5 phosphate buffer solution, N-n-undecyl-N'-(sodium-p-aminobenzenesulfonate) thiourea (UPT) produced a pair of redox peaks on the bare glassy carbon electrode. At the multi-walled carbon nanotube (MWNT) modified electrode, the electrochemical behavior of UPT enhanced greatly. In the presence of bovine serum albumin (BSA), the peak currents of UPT decreased linearly due to the formation of a super-molecular complex. This method was successfully applied to the determination of BSA in a bovine serum sample.


Assuntos
Eletroquímica , Soroalbumina Bovina/química , Tioureia/química , Animais , Eletrodos , Nanotubos de Carbono , Oxirredução
19.
J Mol Model ; 14(12): 1111-7, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18682993

RESUMO

In this paper, we proposed a new method for the determination of either human serum albumin (HSA) or 5-Aminosalicylic acid (5-ASA) by synchronous fluorescence spectra and examined the interaction between them using the molecular modeling method under simulative physiological conditions. The optimum conditions of synchronous fluorometric determination of HSA were investigated and the method was successfully applied to the determination of 5-ASA added to serum, urine, and saliva samples. The linear range of the determination of HSA and 5-ASA were 1.60 - 414 microg mL(-1) and 0.76 -22.95 microg mL(-1), the detection limits were 0.552 microg mL(-1) and 0.38 microg mL(-1), respectively. In addition, the effect of various common ions on the determination of HSA with 5-ASA was also discussed at room temperature.


Assuntos
Mesalamina/análise , Mesalamina/química , Modelos Moleculares , Albumina Sérica/análise , Albumina Sérica/química , Sítios de Ligação , Humanos , Concentração de Íons de Hidrogênio , Mesalamina/metabolismo , Albumina Sérica/metabolismo , Espectrometria de Fluorescência , Temperatura
20.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 43(1): 41-3, 2008 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-18380974

RESUMO

OBJECTIVE: To evaluate the shaping ability of two nickel-titanium rotary systems (ProTaper and Hero642) in simulated S-shaped canals. METHODS: Thirty simulated S-shaped canals were randomly divided into three groups and prepared by ProTaper, Hero642, ProTaper combined with Hero642 respectively. All the canals were scanned before and after instrumentation, and the amount of material removed in the inner and outer wall and the canal width after instrumentation were measured with a computer image analysis program. RESULTS: There was significant difference in the amount of material removed at the inner side of apical curvature and outer side of apex between ProTaper combined with Hero642 and ProTaper files (P < 0.05) at the same tip size. The inner and outer wall of the canals were evenly prepared by ProTaper combined with Hero642, and the taper of canals were better than those prepared by Hero642. CONCLUSIONS: ProTaper combined with Hero 642 had better shaping ability to maintain the original shape and could create good taper canals in the simulated S-shaped canal model.


Assuntos
Cavidade Pulpar , Níquel , Preparo de Canal Radicular/instrumentação , Titânio , Ligas Dentárias , Instrumentos Odontológicos , Modelos Dentários , Falha de Equipamento , Desenho de Aparelho Ortodôntico , Preparo de Canal Radicular/métodos
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