Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
1.
Arch Virol ; 162(5): 1413-1418, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28138777

RESUMO

Parainfluenza virus 5 (PIV5) is widespread in mammals and humans. Up to now, there is little information about PIV5 infection in lesser pandas. In this study, a PIV5 variant (named ZJQ-221) was isolated from a lesser panda with respiratory disease in Guangzhou zoo in Guangdong province, southern China. The full-length genome of ZJQ-221 was found to be 15,246 nucleotides and consisted of seven non-overlapping genes encoding eight proteins (i.e., NP, V, P, M, F, SH, HN and L). Sequence alignment and genetic analysis revealed that ZJQ-221 shared a close relationship with a PIV5 strain of canine-origin (1168-1) from South Korea. The findings of this study confirm the presence of PIV5 in lesser panda and indicate this mammal as a possible natural reservoir. Furthermore they highlight the urgent need to strengthen viral surveillance and control of PIV5 in zoo animals.


Assuntos
Ailuridae/virologia , DNA Viral/genética , Genoma Viral/genética , Vírus da Parainfluenza 5/genética , Infecções por Rubulavirus/veterinária , Animais , Animais de Zoológico/virologia , Sequência de Bases , Linhagem Celular , Chlorocebus aethiops , Vírus da Parainfluenza 5/isolamento & purificação , Infecções por Rubulavirus/virologia , Análise de Sequência de DNA , Células Vero
2.
Anal Bioanal Chem ; 406(30): 8049-58, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25354887

RESUMO

A rapid and sensitive method for the screening and selective quantification of antibiotics in urine by two-dimensional ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was developed. This method allowed the injection of 200 µL urine extract. The 200-µL injection volume used in this method increased the absolute sensitivity for target antibiotics in solvent by an average 13.3 times, with a range from 8.4 to 28.5 times, compared with the 10-µL conventional injection volume. A 96-well solid phase extraction procedure was established to eliminate the contamination on the chromatographic column resulting from the large-volume injection and increase the throughput of sample preparation. Fourteen target antibiotics from six common categories (ß-lactams, quinolones, tetracyclines, macrolides, sulfonamides, and chloramphenicols) were selected as model compounds, and a database containing an additional 74 antibiotics was compiled for posttarget screening. The limit of detection of the target antibiotics, defined as a signal-to-noise ratio of 3, ranged from 0.04 to 1.99 ng/mL. The mean interday recoveries ranged between 79.6 and 121.3 %, with a relative standard deviation from 2.9 to 18.3 % at three spiking levels of 20 ng/mL, 50 ng/mL, and 100 ng/mL. This method was successfully applied in 60 real urine samples from schoolchildren aged 8-11 years, and four target antibiotics (azithromycin, sulfadiazine, trimethoprim, and oxytetracycline) and two posttarget antibiotics (sulfadimidine and cefaclor) were found in the urine samples. This method can be used as a large-scale biomonitoring tool for exposure of the human population to antibiotics.


Assuntos
Antibacterianos/urina , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Criança , Cromatografia Líquida de Alta Pressão/economia , Cromatografia Líquida de Alta Pressão/instrumentação , Desenho de Equipamento , Humanos , Limite de Detecção , Espectrometria de Massas/economia , Espectrometria de Massas/instrumentação , Razão Sinal-Ruído , Fatores de Tempo
3.
Anal Bioanal Chem ; 405(12): 4313-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23430180

RESUMO

Steroid hormone levels in human urine are convenient and sensitive indicators for the impact of phthalates and/or bisphenol A (BPA) exposure on the human steroid hormone endocrine system. In this study, a rapid and sensitive method for determination of 14 phthalate metabolites, BPA, and ten endogenous steroid hormones in urine was developed and validated on the basis of ultra-performance liquid chromatography coupled with electrospray ionization triple quadrupole mass spectrometry. The optimized mixed-mode solid phase-extraction separated the weakly acidic or neutral BPA and steroid hormones from acidic phthalate metabolites in urine: the former were determined in positive ion mode with a methanol/water mobile phase containing 10 mM ammonium formate; the latter were determined in negative ion mode with a acetonitrile/water mobile phase containing 0.1 % acetic acid, which significantly alleviated matrix effects for the analysis of BPA and steroid hormones. Dansylation of estrogens and BPA realized simultaneous and sensitive analysis of the endogenous steroid hormones and BPA in a single chromatographic run. The limits of detection were less than 0.84 ng/mL for phthalate metabolites and less than 0.22 ng/mL for endogenous steroid hormones and BPA. This proposed method had satisfactory precision and accuracy, and was successfully applied to the analyses of human urine samples. This method could be valuable when investigating the associations among endocrine-disrupting chemicals, endogenous steroid hormones, and relevant adverse outcomes in epidemiological studies.


Assuntos
Compostos Benzidrílicos/urina , Disruptores Endócrinos/urina , Hormônios/urina , Fenóis/urina , Ácidos Ftálicos/urina , Extração em Fase Sólida/métodos , Esteroides/urina , Cromatografia Líquida de Alta Pressão/economia , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Limite de Detecção , Extração em Fase Sólida/economia , Espectrometria de Massas em Tandem/economia , Espectrometria de Massas em Tandem/métodos , Fatores de Tempo
4.
Environ Health ; 11: 79, 2012 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-23083070

RESUMO

BACKGROUND: There is increasing evidence suggesting that Bisphenol A (BPA), one of the highest volume chemicals produced worldwide, can interfere with the body's natural weight control mechanisms to promote obesity. However, epidemiological studies for this are limited, especially for children. METHODS: A cross-sectional study was conducted to investigate the association between BPA exposure and body mass index (BMI) in school children. Three primary and three middle schools were randomly selected from 26 primary and 30 middle candidate schools in Changning District of Shanghai City in China. According to the BMI-based criteria by age and sex for screening of overweight or obese children, we randomly chose 20 obese, 10 overweight, and 30 normal weight children aged 8-15 years of age from each selected school. First morning urine was collected and total urine BPA concentrations were determined by ultra-performance liquid chromatography tandem mass spectrometry. Multiple linear regression analysis was conducted to examine the association of urine BPA concentrations and daily intake estimates with BMI. RESULTS: BPA was detected in 84.9% of urine samples with a geometric mean of 0.45 ng/mL. The daily intake estimates ranged from 0.03 µg/day to 1.96 µg/day with a geometric mean of 0.37 µg/day. The average urine BPA concentrations and daily intake estimates were similar for boys and girls, but significantly higher in older children than younger ones, and showed an increasing trend with BMI. Multiple linear regression analyses showed that urine BPA concentrations were significantly associated with increasing BMI values in all subjects after adjustment for age and sex and the results were similar before and after corrected by urine specific gravity. When stratified by age or sex, the associations remained significant in females and in those 8-11 years of age before corrected by specific gravity. Similar results were shown for the association between BMI and daily intake estimates. CONCLUSIONS: There is a possibility that BPA exposure increases BMI in school children. Given the cross-sectional nature of this study, longitudinal studies are warranted to confirm BPA exposure as a contributor to increased BMI in children.


Assuntos
Compostos Benzidrílicos/urina , Índice de Massa Corporal , Poluentes Ambientais/urina , Fenóis/urina , Adolescente , Criança , China , Estudos Transversais , Monitoramento Ambiental , Feminino , Humanos , Masculino , Estudantes
5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 37(3): 480-3, 2006 May.
Artigo em Chinês | MEDLINE | ID: mdl-16761440

RESUMO

OBJECTIVE: To develop a capillary gas chromatographic method for the determination of mannitol in health food. METHODS: Mannitol was extracted from the sample with water by ultrasonic wave. The aliquot of sample solution was acetylated to form mannitol hexacetate with lower boiling point. Then the derivative was separated with the use of SPB-608 capillary chromatographic column and determined by flame ionization detector (FID) at the column temperature of 180 degrees C, the detector temperature of 210 degrees C and the nitrogen flow rate of 30 mL/min. RESULTS: The linear range of this method was 0.05-10.00 mg/mL and the limit of detection of was 0.01 mg/mL. The within-day and between-days precisions were 4.4% and 7.3%-7.6%, respectively. The average recoveries were 84.6%-107.6%. Mannitol could be separated from glucose, inositol and sorbitol under the optimum chromatographic condition. CONCLUSION: The results demonstrate that the method has the advantages of simplicity, accuracy and sensitivity. It is suitable for the determination of mannitol in health food.


Assuntos
Alimentos Orgânicos/análise , Manitol/análise , Cromatografia Gasosa/métodos , Humanos
6.
Artigo em Inglês | MEDLINE | ID: mdl-22963687

RESUMO

This study developed and validated a sensitive analytical method for simultaneous screening of four classes of endocrine-disrupting chemicals (i.e. progestogens, androgens, oestrogens and phenols) in milk and powdered milk using ultra-performance liquid chromatography (UPLC) coupled with electrospray ionisation quadrupole time-of-flight mass spectrometry (QTOF-MS). Dansylation of oestrogens and phenols enhanced the ionisation efficiency and shifted the ionisation mode from negative to positive, which allowed for the simultaneous analysis of four EDCs in one chromatographic run. An efficient sample pre-treatment minimised the matrix effects. The mass errors for the precursor and product ions for 26 target compounds varied between -2.8 and 2.3 mDa; and the limits of detection (signal-to-noise ratio = 3) for milk and powdered milk were less than 0.04 µg l(-1) and 0.10 µg kg(-1), respectively. The proposed method was successfully used to analyse multiple types of real samples, including normal temperature whole milk, infant formula and whole powdered milk. In 11 samples, two target compounds, progesterone and androstenedione, were detected. The progesterone concentrations ranged from 8.1 to 12.7 µg l(-1) in milk, and from 1.2 to 32.0 µg kg(-1) in infant formulas and whole powdered milks. The androstenedione concentrations varied from 0.39 to 0.79 µg l(-1) in milks, and from 0.29 to 1.2 µg kg(-1) in infant formulas and whole powdered milks. Two post-target compounds, one isomer of oestriol and 5α-dihydroprogesterone, were tentatively identified by post-target analysis in two of 11 real samples.


Assuntos
Cromatografia Líquida/métodos , Compostos de Dansil/química , Disruptores Endócrinos/química , Espectrometria de Massas/métodos , Leite/química , Animais , Análise de Alimentos/métodos , Contaminação de Alimentos , Manipulação de Alimentos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa