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1.
Beilstein J Nanotechnol ; 10: 2459-2467, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31921524

RESUMO

A symmetry-breaking nanostructure is proposed to achieve multiple Fano resonances. The nanostructure consists of an asymmetric ring resonator coupled to a plasmonic waveguide. The broken symmetry is introduced by deviating the centers of regular ring. New resonant modes that are not accessible through a regular symmetric ring cavity are excited. Thus, one asymmetric cavity can provide more than one resonant mode with the same mode order. As a result, the interval of Fano resonances is greatly reduced. By combining different rings with different degrees of asymmetry, multiple Fano resonances are generated. Those Fano resonances have different dependences on structural parameters due to their different physical origin. The resonance frequency and resonance peak number can be arbitrarily adjusted by changing the degree of asymmetry. This research may provide new opportunities to design on-chip optical devices with great tuning performance.

2.
Biomed Environ Sci ; 31(1): 76-80, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29409588

RESUMO

The molecular pathogenesis of T-2 toxin-induced cartilage destruction has not been fully unraveled yet. The aim of this study was to detect changes in serum metabolites in a rat anomaly model with articular cartilage destruction. Thirty healthy male Wistar rats were fed a diet containing T-2 toxin (300 ng/kg chow) for 3 months. Histopathological changes in femorotibial cartilage were characterized in terms of chondrocyte degeneration/necrosis and superficial cartilage defect, and the endogenous metabolite profile of serum was determined by UPLC/Q-TOF MS. Treated rats showed extensive areas of chondrocyte necrosis and superficial cartilage defect in the articular cartilage. In addition, 8 metabolites were found to change significantly in these rats compared to the control group, including lysoPE (18:0/0:0), lysoPC(14:0), lysoPC[18:4 (6Z,9Z,12Z,15Z)], lysoPC[(16:1(9Z)], lysoPC(16:0), L-valine, hippuric acid, and asparaginyl-glycine. These 8 metabolites associated with cartilage injury are mainly involved in phospholipid and amino acid metabolic pathways.


Assuntos
Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/metabolismo , Metabolômica , Toxina T-2/toxicidade , Animais , Cromatografia Líquida , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Espectrometria de Massas/métodos , Ratos , Ratos Wistar
3.
Asian Pac J Cancer Prev ; 14(12): 7203-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24460276

RESUMO

Recent studies suggested that the ovarian cancers with negative excision repair cross-complementation group 1 enzyme (ERCC1) expression have a better response to platinum-based chemotherapy than those with positive ERCC1 expression. The objective of this study was to evaluate whether ERCC1 expression is associated with response to platinum-based chemotherapy in ovarian cancers. MEDLINE, PubMed, Web of Science and CNKI databases were used for searching studies relating to ERCC1 protein expression and response to platinum-based chemotherapy in ovarian cancers. Statistical analysis was based on the method for a fixed effects meta-analysis. Pooled odds ratios (ORs) with 95% confidence intervals for ERCC1 protein expression and response to platinum- based chemotherapy were generated. Publication bias was investigated with Begg's test. Five studies involving 306 patients with ovarian cancer were included. Compared to patients with positive ERCC1 expression, those with negative ERCC1 expression had a better response to platinum-based chemotherapy. The pooled OR was 5.264 (95% CI: 2.928 - 9.464, P < 0.001) and publication bias was not found (P = 0.904). The result was similar in both in Asians and Caucasians (P < 0.001 and P = 0.028, respectively). ERCC1 protein expression status is significantly associated with response to platinum-based chemotherapy in ovarian cancers.


Assuntos
Antineoplásicos/uso terapêutico , Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Platina/uso terapêutico , Feminino , Humanos , Prognóstico
4.
Artigo em Chinês | MEDLINE | ID: mdl-22931877

RESUMO

OBJECTIVE: To investigate the pollution of hexavalent chromium in the electroplating workplace and screen the biomarkers of chromium exposure. MATERIAL: Field occupational health investigation was conducted in 25 electroplating workplaces. 157 electroplating workers and 93 healthy unexposed controls were recruited. The epidemiological information was collected with face to face interview. Chromium in erythrocytes was determined by graphite furnace atomic absorption spectrophotometer. RESULTS: The median of short-term exposure concentration of chromium in the air at electroplating workplace was 0.06 mg/m(3) (median) and ranging from 0.01 (detect limit) to 0.53 mg/m(3)). The median concentration of Cr (VI) in erythrocytes in electroplating workers was 4.41 (2.50 ∼ 5.29) µg/L, which was significantly higher than that in control subjects [1.54 (0.61 ∼ 2.98) µg/L, P < 0.01]. After stratified by potential confounding factors such as gender, age, smoking status and alcohol consumption, significant differences still existed between electroplating workers and control subjects, except for the subjects of age less than 30 years old (P = 0.11). CONCLUSION: There was hexavalent chromium pollution in electroplating workplace. Occupational hazards prevention measures should be taken to control the chromium pollution hazards.


Assuntos
Poluentes Ocupacionais do Ar/análise , Cromo/sangue , Galvanoplastia , Exposição Ocupacional/análise , Adulto , Monitoramento Ambiental , Eritrócitos/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Local de Trabalho , Adulto Jovem
5.
BMC Public Health ; 11: 224, 2011 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-21481275

RESUMO

BACKGROUND: Occupational exposure to chromium compounds may result in adverse health effects. This study aims to investigate whether low-level hexavalent chromium (Cr(VI)) exposure can cause DNA damage in electroplating workers. METHODS: 157 electroplating workers and 93 control subjects with no history of occupational exposure to chromium were recruited in Hangzhou, China. Chromium levels in erythrocytes were determined by graphite furnace atomic absorption spectrophotometer. DNA damage in peripheral lymphocytes was evaluated with the alkaline comet assay by three parameters: Olive tail moment, tail length and percent of DNA in the comet tail (tail DNA%). Urinary 8-OHdG levels were measured by ELISA. RESULTS: Chromium concentration in erythrocytes was about two times higher in electroplating workers (median: 4.41 µg/L) than that in control subjects (1.54 µg/L, P < 0.001). The medians (range) of Olive tail moment, tail length and tail DNA% in exposed workers were 1.13 (0.14-6.77), 11.17 (3.46-52.19) and 3.69 (0.65-16.20), and were significantly higher than those in control subjects (0.14 (0.01-0.39), 3.26 (3.00-4.00) and 0.69 (0.04-2.74), P < 0.001). Urinary 8-OHdG concentration was 13.65 (3.08-66.30) µg/g creatinine in exposed workers and 8.31 (2.94-30.83) µg/g creatinine in control subjects (P < 0.001). The differences of urinary 8-OHdG levels, Olive tail moment, tail length and tail DNA% between these two groups remained significant (P < 0.001) even after stratification by potential confounding factors such as age, gender, and smoking status. Chromium exposure was found to be positively associated with chromium levels in erythrocytes, urinary 8-OHdG levels, Olive tail moment, tail length and tail DNA%. Positive dose-response associations were also found between chromium levels in erythrocytes and Olive tail moment, tail length and tail DNA%. CONCLUSION: The findings in this study indicated that there was detectable chromium exposure in electroplating workers. Low-level occupational chromium exposure induced DNA damage.


Assuntos
Carcinógenos Ambientais/toxicidade , Cromo/toxicidade , Dano ao DNA , Galvanoplastia , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Adulto , Poluentes Ocupacionais do Ar/análise , Carcinógenos Ambientais/análise , Estudos de Casos e Controles , China , Cromo/sangue , Cromo/urina , Feminino , Humanos , Exposição por Inalação/análise , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/sangue , Doenças Profissionais/urina , Exposição Ocupacional/análise , Fatores de Tempo
6.
J Zhejiang Univ Sci B ; 11(4): 258-66, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20349522

RESUMO

Regenerating gene IV (RegIV), a member of the regenerating gene family discovered in 2001, has been found to be involved in malignancy in several different organs including the stomach, colorectum, pancreas and prostate, but the overall expression profile of RegIV has not been reported. To learn more about RegIV, we evaluated its distribution by immunohistochemistry (IHC) in a total of 360 samples including 24 types of normal tissue, 40 benign and malignant lesions, and 18 neuroendocrine tumors. We found that in normal tissues, in addition to its relative specificity for the gastrointestinal tract, RegIV was detected in the adrenal gland and mammary gland. Among all the malignancies of various histological types under evaluation, RegIV was found mostly in adenocarcinomas. Studies on additional sets of colorectal tumor samples showed that RegIV expression was predominant in colorectal adenoma (87.5%) and peritumoral tissue (100%) but not in cancer tissue (30.8%). Among neuroendocrine tumors, RegIV had a relatively restricted expression to those of digestive system.


Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/metabolismo , Trato Gastrointestinal/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Lectinas Tipo C/biossíntese , Tumores Neuroendócrinos/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica/métodos , Lectinas Tipo C/fisiologia , Masculino , Proteínas Associadas a Pancreatite , Sensibilidade e Especificidade , Distribuição Tecidual
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