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1.
J Am Chem Soc ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32053353

RESUMO

Topological defects, such as vortices and skyrmions, provide a wealth of splendid possibilities to new nanoscale devices because of their marvelous electronic, magnetic, and mechanical behaviors. Recently, great advances have been made in the study of ferroelectric vortex in conventional perovskite oxides, such as BaTiO3, and BiFeO3. Despite extensive interest, however, no intriguing ferroelectric vortex structures have yet been found in organic-inorganic hybrid perovskites (OIHPs), which are desirable for their mechanical flexibility, ease of fabrication, and low acoustical impedance. We observed the robust vortex-antivortex topological configurations in a two-dimensional (2D) layered OIHP ferroelectric (4,4-DFPD)2PbI4 (4,4-DFPD is 4,4-difluoropiperidinium). This provides future directions to the study of perovskites, and makes it a promising alternative for nanoscale ferroelectric devices in medical, micromechanical, and biomechani-cal applications.

2.
J Am Chem Soc ; 142(2): 1077-1082, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31851495

RESUMO

Piezoelectric sensors that can work under various conditions with superior performance are highly desirable with the arrival of the Internet of Things. For practical applications, a large piezoelectric voltage coefficient g and a high Curie temperature Tc are critical to the performance of piezoelectric sensors. Here, we report a two-dimensional perovskite ferroelectric (4-aminotetrahydropyran)2PbBr4 [(ATHP)2PbBr4] with a saturated polarization of 5.6 µC cm-2, high Tc of 503 K [above that of BaTiO3 (BTO, 393 K)], and extremely large g33 of 660.3 × 10-3 V m N-1 [much beyond that of Pb(Zr,Ti)O3 (PZT) ceramics (20 to 40 × 10-3 V m N-1), more than 2 times higher than that of poly(vinylidene fluoride) (PVDF, about 286.7 × 10-3 V m N-1)]. Combined with the advantages of molecular ferroelectrics, such as light weight, easy and environmentally friendly processing, and mechanical flexibility, (ATHP)2PbBr4 would be a competitive candidate for next-generation smart piezoelectric sensors in flexible devices, soft robotics, and biomedical devices.

3.
Medicine (Baltimore) ; 98(38): e17014, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31567938

RESUMO

The coronary collateral circulation (CCC) is an alternative source of blood supply when the original vessels fail to provide sufficient blood. The accurate detection of CCC is critical for the treatment of ischemic heart disease, especially when the stent surgery is not an option. The assessment of minute vessels such as coronary collateral arteries is challenging. The objective of this study was to assess the feasibility of detection and classification of CCC using the192-slice third-generation dual-source computed tomography angiography (192-slice DSCT CTA).Eight hundred patients (450 men and 350 women, mean age: 56 ±â€Š11 years) with complete or subtotal occlusion of at least 1 major coronary artery were enrolled for our study. February 2016 and September 2018, the patient both 192-slice DSCT CTA and conventional coronary angiography (CAG) were performed in all enrolled patients. The interval between two approaches for a given patient was 6.1 ±â€Š3.7 days (Range: 1-15). The diagnostic accuracy of 192-slice DSCT CTA was evaluated by comparing it with that of CAG. The identified CCC was graded according to the Rentrop classification.The prevalence among patients of having at least 1 CCC was 43.8%. The sensitivity for detecting CCC by 192-slice DSCT was 91.7% (95% CI: 88.3% to 94.3%), specificity was 95.5% (95% CI: 93.1% to 97.2%), positive predictive value was 94.3% (95% CI: 91.5% to 96.2%), and negative predictive value was 93.3% (95% CI: 90.9% to 95.3%). Cohen-Kappa analysis showed that the consistency of the correct classification of CCC using CAG and 192-slice DSCT was very high with the kappa coefficient (κ) of 0.94 (95% CI: 0.91-0.96, P value = .01). Additionally, the radiation dose for 192-slice DSCT was as low as 0.42 ±â€Š0.04 mSv (range, 0.35-0.43 mSv).The 192-slice DSCT CTA is a reliable and sensitive non-invasive method for the evaluation of CCC with low radiation doses.


Assuntos
Circulação Colateral , Angiografia por Tomografia Computadorizada/normas , Doença da Artéria Coronariana/diagnóstico por imagem , Circulação Coronária , Doença da Artéria Coronariana/classificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
4.
J Phys Chem Lett ; 10(15): 4237-4244, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31295405

RESUMO

Molecular rotational motion is crucial in artificial molecular machines and is expected to be very significant for the development of an electronic information molecular machine as mentioned in the 2016 Nobel Prize. However, controlling multiple motor modes is a huge challenge. Here, we report a case in which the structural phase transition effectively triggers multiple motor modes by regulating the rotational speed of the cation and/or anion. A novel switchable crystalline supramolecular rotor, [(cyclohexylammonium)(18-crown-6)] FSO3 (1), exhibits prominent temperature-dependent double switching behavior at 157.9 and 389.1 K induced by the variation of the rotational speed of the FSO3- anion (which acts as a super miniature rotator) in response to temperature. Moreover, it exhibits significant relaxation behavior and excellent pyroelectric switch characteristics. To the best of our knowledge, this might be the first discovery of the stator-rotator double switch with a relaxation effect, which could be a promising candidate for a slow/fast responsive double switch over a wide temperature range.

5.
Inorg Chem ; 58(7): 4600-4608, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30896161

RESUMO

With regard to the artificial molecular motor that was recognized with the 2016 Nobel Prize, this success proves the great scientific significance of rotary motor-type motion at the molecular level, which has been expected to play an invaluable role in the development of electronic information molecular materials. However, designing electronic information-critical high-temperature molecular motors has always been a huge challenge. Since we discovered [(CH3)3NCH2Cl]MnCl3, this cation rotation pattern with a motor-type motion structure has continued to attract our attention. Considering a strategy that combines molecular machines with dielectric theory, ( N, N-dimethylpiperidinium)CdCl3, the new dielectric molecular motor material that exhibits superior physical properties, could be considered to be an excellent dielectric switch based on its electric field and temperature. Crystal structure analyses reveal that the reversible phase transition is mainly induced by the unusual chair-to-rotator motion of cations. Because of the unprecedented leaping structural transition from P63/ mmc to P21/ c and the rotating motor-type motion structure, the material exhibits remarkable anisotropy and outstanding dielectric switching characteristics. These findings open a new avenue for the design and assembly of novel molecular motor materials in the field of electronic information.

6.
ChemSusChem ; 11(16): 2730-2736, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-29851295

RESUMO

The rational design of highly efficient and durable oxygen reduction reaction (ORR) catalysts is critical for the commercial application of fuel cells. Herein, three-dimensional graphene (3D-G) is synthesized by the template method, which used coal tar pitch as the carbon source and nano MgO as the template. Then, spinel MnCo2 O4 is in situ supported on the 3D-G by a facile hydrothermal method, giving MnCo2 O4 /3D-G. The resultant MnCo2 O4 /3D-G retains the multilayered mesoporous graphene structure where MnCo2 O4 nanoparticles are deposited on the inner walls of pores in the 3D-G. The catalyst MnCo2 O4 /3D-G shows high electrocatalytic activity with a half-wave potential of 0.81 V versus reversible hydrogen electrode, which is clearly superior to those of MnCo2 O4 /reduced graphene oxide (0.78 V), MnCo2 O4 /carbon nanotubes (0.74 V), MnCo2 O4 /C (0.72 V), and 20 wt % Pt/C (0.80 V). The electron transfer number of MnCo2 O4 /3D-G indicates a four-electron process of ORR. The durability test demonstrates that the MnCo2 O4 /3D-G catalyst has a much better durability than 20 wt % Pt/C. Our work makes an inspiring strategy to prepare high-performance electrocatalysts for the development of fuel cells.

7.
Braz J Med Biol Res ; 51(6): e6997, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29694513

RESUMO

MicroRNAs (miRNAs) have been reported to be associated with heart valve disease, which can be caused by inflammation. This study aimed to investigate the functional impacts of miR-27a on TNF-α-induced inflammatory injury in human mitral valve interstitial cells (hMVICs). hMVICs were subjected to 40 ng/mL TNF-α for 48 h, before which the expressions of miR-27a and NELL-1 in hMVICs were altered by stable transfection. Trypan blue staining, BrdU incorporation assay, flow cytometry detection, ELISA, and western blot assay were performed to detect cell proliferation, apoptosis, and the release of proinflammatory cytokines. We found that miR-27a was lowly expressed in response to TNF-α exposure in hMVICs. Overexpression of miR-27a rescued hMVICs from TNF-α-induced inflammatory injury, as cell viability and BrdU incorporation were increased, apoptotic cell rate was decreased, Bcl-2 was up-regulated, Bax and cleaved caspase-3/9 were down-regulated, and the release of IL-1ß, IL-6, and MMP-9 were reduced. NELL-1 was positively regulated by miR-27a, and NELL-1 up-regulation exhibited protective functions during TNF-α-induced cell damage. Furthermore, miR-27a blocked JNK and Wnt/ß-catenin signaling pathways, and the blockage was abolished when NELL-1 was silenced. This study demonstrated that miR-27a overexpression protected hMVICs from TNF-α-induced cell damage, which might be via up-regulation of NELL-1 and thus modulation of JNK and Wnt/ß-catenin signaling pathways.


Assuntos
Inflamação/induzido quimicamente , MicroRNAs/metabolismo , Valva Mitral/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Adulto , Apoptose , Proliferação de Células , Sobrevivência Celular , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Doenças das Valvas Cardíacas/prevenção & controle , Humanos , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Valva Mitral/citologia , Valva Mitral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Regulação para Cima
8.
Braz. j. med. biol. res ; 51(6): e6997, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-889113

RESUMO

MicroRNAs (miRNAs) have been reported to be associated with heart valve disease, which can be caused by inflammation. This study aimed to investigate the functional impacts of miR-27a on TNF-α-induced inflammatory injury in human mitral valve interstitial cells (hMVICs). hMVICs were subjected to 40 ng/mL TNF-α for 48 h, before which the expressions of miR-27a and NELL-1 in hMVICs were altered by stable transfection. Trypan blue staining, BrdU incorporation assay, flow cytometry detection, ELISA, and western blot assay were performed to detect cell proliferation, apoptosis, and the release of proinflammatory cytokines. We found that miR-27a was lowly expressed in response to TNF-α exposure in hMVICs. Overexpression of miR-27a rescued hMVICs from TNF-α-induced inflammatory injury, as cell viability and BrdU incorporation were increased, apoptotic cell rate was decreased, Bcl-2 was up-regulated, Bax and cleaved caspase-3/9 were down-regulated, and the release of IL-1β, IL-6, and MMP-9 were reduced. NELL-1 was positively regulated by miR-27a, and NELL-1 up-regulation exhibited protective functions during TNF-α-induced cell damage. Furthermore, miR-27a blocked JNK and Wnt/β-catenin signaling pathways, and the blockage was abolished when NELL-1 was silenced. This study demonstrated that miR-27a overexpression protected hMVICs from TNF-α-induced cell damage, which might be via up-regulation of NELL-1 and thus modulation of JNK and Wnt/β-catenin signaling pathways.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Inflamação/induzido quimicamente , MicroRNAs/metabolismo , Valva Mitral/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Apoptose , Proliferação de Células , Sobrevivência Celular , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Doenças das Valvas Cardíacas/prevenção & controle , Inflamação/patologia , Valva Mitral/citologia , Valva Mitral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Regulação para Cima
9.
J Agric Food Chem ; 65(13): 2867-2875, 2017 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-28322048

RESUMO

Salbutamol, a selective ß2-agonist, endangers the safety of animal products because of its illegal use in food animals. In this work, residues of salbutamol and its metabolites were investigated to select appropriate targets and marker residues for monitoring the illegal use of salbutamol. Ten metabolites of salbutamol were identified from plasma, urine, liver, and kidney samples; of these, six were newly identified. There were significant differences (P < 0.01) between the parent (nonconjugated) and total (conjugated + nonconjugated) salbutamol concentrations in plasma, urine, liver, and kidney tissues. Salbutamol residues in urine were relatively higher than those in plasma and other internal tissues during the dosing period and were rapidly eliminated from plasma, heart, spleen, and kidney tissues during the withdrawal time. Total salbutamol was identified as more preferable than parent salbutamol as a marker residue, and urine and eye tissues were found to be more suitable as targets for preslaughter and postslaughter monitoring of the illegal use of salbutamol in beef cattle.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/química , Agonistas de Receptores Adrenérgicos beta 2/metabolismo , Albuterol/química , Albuterol/metabolismo , Resíduos de Drogas/química , Resíduos de Drogas/metabolismo , Agonistas de Receptores Adrenérgicos beta 2/sangue , Agonistas de Receptores Adrenérgicos beta 2/urina , Albuterol/sangue , Albuterol/urina , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Rim/química , Rim/metabolismo , Fígado/química , Fígado/metabolismo , Masculino , Espectrometria de Massas
10.
J Mass Spectrom ; 50(7): 906-13, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26349645

RESUMO

This study investigated the ion mobility (IM) and the collision cross section (CCS) of fatty acids (FAs) using electrospray IM MS. The IM analysis of 18 FA ions showed intriguing differences among the saturated FAs, monounsaturated FAs, multi-unsaturated FAs, and cis-isomer/trans-isomer with respect to the aliphatic tail chains. The length of aliphatic tail chain present in the ion structures had a strong influence on the differentiation of drift, while the number of double bond showed a weaker influence. The tiny drift differences between cis-isomer and trans-isomer were also observed. In the CCS measurements, two internal standards were involved in the mobility calibration and accuracy estimation. It insured our empirical CCS values were of high experimental precision (±0.35% or better) and accuracy (±0.25% or better). Moreover, the mass-to-charge ratio (m/z) - mobility plots obtained by ion mobility spectrometry with mass spectrometry analysis of FAs - was used to investigate the structural relationship between the molecules. Each series of FAs sharing a similar structure was aligned in the linear plot. Finally, the developed procedure was applied to the determination of FAs in rat adipose tissues, and it allowed the presence of 13 FAs to be confirmed with their exact masses and CCS values. These studies reveal the direct relationship between the behaviors in IM and the molecular structures and thus may provide further validations to the FA identification process.

11.
Anal Chim Acta ; 887: 148-154, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26320796

RESUMO

A rapid method for fatty acids (FAs) comparative profiling based on carboxyl-specific stable isotope labeling (SIL) and direct infusion electrospray ionization-ion mobility-mass spectrometry (ESI-IM-MS) is established. The design of the method takes advantage of the three-dimensional characteristics of IM-MS including drift time, m/z and ion intensity, for comparison of d0-/d6-2,4-dimethoxy-6-piperazin-1-yl pyrimidine (DMPP)-labeled FAs. In particular, without chromatographic separation, the method allowed direct FAs profiling in complex samples due to the advantageous priority of DMPP in signal enhancement as well as the extra resolution that IM-MS offered. Additionally, the d0-/d6-DMPP-labeled FAs showed expected features, including very similar drift times, 6 Da mass deviations, specific reporter ions, similar MS responses, and adherence to the drift time rule regarding the influence of carbon chain length and unsaturation on relative drift times. Therefore, the introduction of isotope analogs minimized the matrix effect and variations in quantification and ensured accurate identification of non-targeted FAs by those typical features. Peak intensity ratios between d0-/d6-DMPP-labeled ions were subsequently used in relative quantification for the detected FAs. The established strategy has been applied successfully in the rapid profiling of trace free FAs between normal and cancerous human thyroid tissues. Sixteen free FAs were found with the increased level with a statistically significant difference (p < 0.05) compared to the normal tissue samples. The integrated SIL technique and ESI-IM-MS are expected to serve as an alternative tool for high-throughput analysis of FAs in complex samples.


Assuntos
Ácidos Graxos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Humanos , Marcação por Isótopo/métodos , Limite de Detecção
12.
Cell Biochem Biophys ; 71(2): 937-43, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25315640

RESUMO

The aim of this study was to investigate characteristic CT manifestations of the group of ovarian thecoma-fibroma. 24 patients (26 lesions) presenting with the ovarian thecoma-fibroma were analyzed retrospectively, and the diagnosis were confirmed by pathology after surgery. Our findings included: 22 patients were unilateral, while 2 were bilateral; 12 lesions were located in the right side of ovary, while 14 lesions were in the left side. Of the 26 lesions, there were ovarian thecoma (16 lesions), fibrothecoma (6 lesions), and fibroma (4 lesions). The largest diameters of tumor ranged from 37 to 231 mm with the mean value of 100 ± 44.29 mm. 14 patients were accompanied by ascites. All the tumors had well-defined borders. The shape of  22 lesions appeared round or oval, and 4 lesions were irregular. The tumors were solid in 19 lesions, cystic in 2 lesions, and mixed in 5 lesions. Most of the tumors were of heterogeneous density. There were no (20 lesions) or slight enhancement (6 lesions) after injection of the contrast medium. CT values of plain scan, arterial phase and venous among three groups had no significant difference. The enhancement were in the range of 0-5 HU in 10 lesions, and 6-17 HU in 16 lesions. In conclusion, the characteristic CT manifestations of the group of ovarian thecoma-fibroma were: often unilateral solid mass with the shape of oval and well defined border; no enhancement or slight enhancement; accompanied by small amount of ascites.


Assuntos
Fibroma/diagnóstico por imagem , Neoplasias Ovarianas/diagnóstico por imagem , Tecoma (Neoplasia)/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Idoso , Feminino , Fibroma/patologia , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Tecoma (Neoplasia)/patologia
13.
Anal Chim Acta ; 757: 39-47, 2012 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-23206394

RESUMO

A method for the rapid simultaneous screening and identification of multiple pesticide residues in vegetables was established using a novel database and gas chromatography in combination with hybrid quadrupole time-of-flight mass spectrometry (GC-QTOF MS). A total of 187 pesticides with different chemical species were measured by GC-QTOF MS to create the database, which collected the retention time and exact masses of ions from the first-stage mass spectrum (MS(1) spectrum) and second-stage mass spectrum (MS(2) spectrum) for each pesticide. The workflow of the created database consisted of "MS(1) screening" for possible pesticides by chemical formula match and "MS(2) identification" for structural confirmation of product ion by accurate mass measurement. To evaluate the applicability of the database, a spinach matrix was prepared by solid phase extraction, spiked with a mixture of 50 pesticides at seven concentrations between 0.1 and 10ppb, and analyzed by GC-QTOF MS. It was found that all of the 50 pesticides with concentrations as low as 5ppb were detected in the "MS(1) screening" step and accurate masses were identified with errors less than 2.5mDa in the "MS(2) identification" step, indicating high sensitivity, accuracy, selectivity and specificity. Finally, to validate the applicability, the new method was applied to four fresh celery, rape, scallion and spinach vegetables from a local market. As a result, a total of 13 pesticides were found, with 11 in celery, 9 in rape, 3 in scallion and 2 in spinach. In conclusion, GC-QTOF MS combined with an exact mass database is one of the most efficient tools for the analysis of pesticide residues in vegetables.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Praguicidas/análise , Verduras/química , Bases de Dados de Compostos Químicos
14.
Biol Pharm Bull ; 35(9): 1568-73, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22975510

RESUMO

Apoptosis is the main form of ß-cell death in diabetes. Ginseng has been used as an anti-diabetic herb for several thousand years in Asia with ginsenoside Rg1 and ginsenoside Rb1 as important active ingredients. In this study, we demonstrated ginsenoside Rg1 and Rb1 protect ß-cells from high glucose/cytokine-induced pancreatic ß-cell apoptosis via inhibiting nitric oxide (NO) production and regulating apoptosis-related genes. Among these genes, Bax, Fas and Caspase-3 gene expressions were up-regulated by high glucose, whereas only Bax and Caspase-3 gene expression were elevated by cytokines. In these two stimuli-induced apoptotic cells, Rg1 down-regulated Fas gene expression, while Rb1 decreased Caspase-3 gene expression. As a conclusion, Fas signal pathway and mitochondria stress is mostly related to anti-diabetes function of ginsenoside Rg1, while Caspase-3 pathway is essential when Rb1 is present.


Assuntos
Apoptose/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Ginsenosídeos/farmacologia , Hipoglicemiantes/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Panax/química , Extratos Vegetais/farmacologia , Animais , Apoptose/genética , Caspase 3/metabolismo , Linhagem Celular , Citocinas/metabolismo , Glucose/efeitos adversos , Células Secretoras de Insulina/metabolismo , Mitocôndrias/efeitos dos fármacos , Óxido Nítrico/biossíntese , Fitoterapia , Ratos , Transdução de Sinais , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Receptor fas/genética , Receptor fas/metabolismo
15.
Clin Lab ; 57(7-8): 543-50, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21888019

RESUMO

BACKGROUND: Chloride channels (ClC) are involved in normal physiological processes and pathology of various diseases. Although it is recognized that suppression of ClC inhibits cell proliferation in different types of cells, the potential function of ClC in cell migration in ovarian cancer is still unclear. In this study, we investigated the effect of the ClC inhibitor, 5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB), on cell migration in the human ovarian cancer cell line SKOV-3 as well as the related signaling pathway involved in this action. METHODS: In this study, cell viability was measured using the MTT assay. Transwell migration method was used to study the effect of NPPB on serum-induced SKOV-3 cell migration. Also, Western blot was performed to detect the phosphorylation levels of ERK1/2 and AKT1 after treatment with NPPB. RESULTS: Both NPPB and LY249002 significantly inhibited serum-induced SKOV-3 cell migration without alteration of cell viability. NPPB's inhibition of phosphorylation of AKT1 was time-dependent (p < 0.05). There was no significant effect on the phosphorylation of ERK1/2 after treatment with NPPB. CONCLUSIONS: ClC plays an important role in ovarian cancer cell migration. NPPB inhibited-SKOV-3 cell migration could be via inactivation of AKT1.


Assuntos
Adenocarcinoma/patologia , Canais de Cloreto/antagonistas & inibidores , Nitrobenzoatos/farmacologia , Neoplasias Ovarianas/patologia , Transdução de Sinais/efeitos dos fármacos , Adenocarcinoma/enzimologia , Inibidores da Angiogênese/farmacologia , Linhagem Celular Tumoral/citologia , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/enzimologia , Movimento Celular/efeitos dos fármacos , Canais de Cloreto/fisiologia , Meios de Cultura/farmacologia , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Flavonoides/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/fisiologia , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/fisiologia , Neoplasias Ovarianas/enzimologia , Fosfatidilinositol 3-Quinases/fisiologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Soro
16.
Environ Sci Technol ; 45(19): 8075-80, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20964291

RESUMO

A fluorochemical industrial park was built in 2004 in Fuxin, China, for the production of polytetrafluoroethylene (PTFE) and perfluorobutane sulfonate (PFBS). Yet little is known about the distribution of fluorochemicals in the environment and in people living in and around the park. In this study, environmental samples were collected from 22 sites in Fuxin to investigate the extent of perfluorinated compound (PFC) contamination in the environment around the park, and in drinking water from the public water supply system and groundwater in shallow aquifers from private wells near the park. Serum samples were also collected from nonoccupationally exposed residents living in Fuxin to determine the PFC load of local residents. As the dominant contaminant of eight target PFCs, the maximum concentrations of perfluorooctanoic acid (PFOA) in sediment and river water of the River Xi along the industrial park were 48 ng/g dry weight and 668 ng/L, respectively; the highest PFOA concentration in groundwater beneath the park was 524 ng/L; and the PFOA levels in drinking water from the public water supply system ranged between 1.3 and 2.7 ng/L. In human serum, PFOA had the geometric mean at 4.3 ng/mL, ranging from 0.02 to 93 ng/mL. This study serves to document what should be the beginning of a long-term surveillance effort to minimize potential exposure of residents living in Fuxin.


Assuntos
Monitoramento Ambiental , Fluorcarbonetos/sangue , Indústrias , Características de Residência , China , Água Potável , Geografia , Sedimentos Geológicos/química , Água Subterrânea/química , Humanos , Modelos Biológicos , Rios/química
17.
Chemosphere ; 80(2): 123-30, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20430414

RESUMO

Perfluorinated compounds (PFCs) have been determined in various matrices within China including water bodies, precipitations, biota and non-occupationally PFCs-exposed populations in recent years, yet little attention has been focused on the distributions of PFCs in urban river sediments from Chinese major metropolises such as Guangzhou and Shanghai so far. In this study, sediment samples of 0-2 cm were collected from 13 sites in the Zhujiang River across Guangzhou and nine sites in the Huangpu River across Shanghai. PFCs analysis on these sediments via high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) system was implemented targeting eight analytes involving perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorododecanoic acid (PFDoA) and perfluorotetradecanoic acid (PFTA). According to the analytical results, total concentrations of PFCs ([summation operator]PFCs) in sediments from the Zhujiang River were between 0.09 and 3.6 ng/g dry weight (dw), with PFOS being the dominant PFC contaminant in the river ranged from below LOD to 3.1 ng/g dw; while [summation operator]PFCs in sediments from the Huangpu River were between 0.25 and 1.1 ng/g dw, with PFOA being the main PFC contaminant in the river determined in the levels of 0.20-0.64 ng/g dw. Additionally, an overall decreasing trend of PFCs contaminations with depth was observed in both of two 60 cm sediment cores from the Zhujiang River and the Huangpu River each.


Assuntos
Monitoramento Ambiental , Fluorcarbonetos/análise , Sedimentos Geológicos/química , Rios/química , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/análise , Caprilatos/análise , China , Cidades , Ácidos Decanoicos/análise , Ácidos Láuricos/análise
18.
Chemosphere ; 77(5): 652-7, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19735931

RESUMO

Perfluorinated compounds (PFCs) have received much attention on their distributions in various matrixes of different areas globally, however, little is known about their existences in river sediments of China. In this study, eight target PFCs including perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorododecanoic acid (PFDoA) and perfluorotetradecanoic acid (PFTA) were determined based upon the upper 10cm surface sediment samples collected from eleven sites covering three main streams of the Daliao River system in northeast China, which received huge amount of industrial and domestic wastewater annually from the neighbouring areas. Analytical results indicated that total concentrations of PFCs were determined in the range of 0.29-1.03ngg(-1) dry weight in sediments from this river system. As the dominant PFCs contaminants in sediment samples, concentrations of PFOS and PFOA were ranged between

Assuntos
Fluorcarbonetos/análise , Sedimentos Geológicos/química , Rios/química , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/análise , Caprilatos/análise , China , Monitoramento Ambiental , Geografia , Ácidos Láuricos/análise
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