RESUMO
The enzyme α-L-fucosidase (AFu) plays an important role in the diagnosis of hepatocellular carcinoma (HCC) and fucosidosis. In this paper, a simple, sensitive and precise method based upon measuring the fluorescence quenching of CdTe semiconductor quantum dots (QDs) was developed for detecting the enzymatic activity of AFu. The detection limit of AFu was 0.01 U/L (n = 3) and the linear relationship was 0.01-4 U/L. The selectivity experiment indicated excellent selectivity for AFu over a number of interfering species. We have also studied the detection mechanism of AFu by X-ray photoelectron spectroscopy (XPS) and found that the quenching effect was caused by the oxidation of tellurium by 2-chloro-4-nitrophenol (2-CNP) which produced in AFu catalytic reaction. Moreover, the AFu sensor based on QDs was used satisfactorily for the assessment of AFu activity in serum samples. It will most probably be applicable in assembling diagnostic microdevice to realize the rapid clinic analysis of AFu.
Assuntos
Compostos de Cádmio/química , Pontos Quânticos , Espectrometria de Fluorescência/métodos , Telúrio/química , alfa-L-Fucosidase/sangue , Carcinoma Hepatocelular/sangue , Fucosidose/sangue , Humanos , Limite de Detecção , Neoplasias Hepáticas/sangue , alfa-L-Fucosidase/análiseRESUMO
A striking elevation of plasma chitotriosidase activity, greater than 150 times the normal median value, was found in two galactosialidosis patients. Furthermore, increased plasma chitotriosidase activity, 10-53 times the normal median value, was also observed in fucosidosis, glycogen storage disease type IV, Alagille syndrome and hydrops fetalis due to congenital herpes virus infection.
Assuntos
Síndrome de Alagille/sangue , Fucosidose/sangue , Galactose/sangue , Doença de Depósito de Glicogênio Tipo IV/sangue , Hexosaminidases/sangue , Hidropisia Fetal/sangue , Humanos , Macrófagos/metabolismoRESUMO
Variations in serum alpha-L-fucosidase activity (AFU) have been studied during childhood and pregnancy. 994 children, ages 1 day to 15 yr, were examined; no sex-linked difference was found, but significant variations according to age were demonstrated. AFU activity rose during the first 10-15 days after birth, remained high during the second month then decreased till the end of the first year, thereafter no significant changes were observed. In pregnancy, AFU activity rose and dropped quickly after delivery; neither hypertension nor fetal distress led to AFU activity changes during pregnancy. Thus, in addition to the great variability of AFU linked to the genetic polymorphism, the physiological factors such as age or pregnancy have to be taken into account to establish the significance of AFU variations in pathological situations.
