Transfer of epinastine to infants through human breast milk.

The purpose of this study was to develop an analytical method for analyzing epinastine in breast milk and maternal plasma samples to determine the safety of epinastine in breastfed infants. Six nursing mothers took epinastine hydrochloride (20 mg) once a day for 7 days, while a nursing mother took it for 30 days. Breast milk and blood samples were collected 2, 4, and 10 h after administration from the volunteers. A liquid chromatography-mass spectrometry system was used to analyze samples pretreated by liquid-liquid extractions. The concentration of epinastine in human milk was 10.3-33.5 ng/mL after 2 h, 9.1-63.8 ng/mL after 4 h, and 8.3-28.9 ng/mL after 10 h. The increase achieved 4 h after administration indicates that epinastine was transferred into human breast milk. However, the milk-to-plasma ratio had a wide range (0.82-3.39), while the relative infant dose at 4 h was 0.36-2.49%, which is lower than the safety level of transferability (10%). Moreover, the plasma levels of epinastine in two infants were slightly below the quantification limit. Overall, our results suggested that epinastine can safely be used by nursing mothers without affecting their infants.

Gene expression assay in blood and various tissues using a single-tube real-time reverse transcription-polymerase chain reaction method using an oligodeoxythymidine-immobilized polymerase chain reaction tube.

A single-tube real-time reverse transcription-polymerase chain reaction (RT-PCR) method has been developed which makes it possible to conduct the entire procedure, from nucleic acid extraction to product detection, in a single PCR tube. In this study, we developed the method using an oligodeoxythymidine-immobilized PCR tube, which enables simple and rapid mRNA extraction and quantification of target genes in blood and other tissues. The beta-actin gene was analyzed from lysates of blood and various tissues using this method. The data showed a good correlation between the plotted threshold cycle values and log(10) of blood and tissue amounts without a reduction in PCR efficiency. Gene expression of interleukin-1beta in blood from lipopolysaccharide (LPS)-stimulated rats and of beta(3)-adrenoceptors in adipose tissue from SHRSP.Z-Lepr (fa)/IzmDmcr (obese SHRSP) rats was also analyzed using the single-tube method, as well as a general real-time RT-PCR method, using RNA purified with a silica membrane column. In both methods, the copy number ratio of interleukin-1beta to beta-actin in LPS-stimulated rats was higher than in control rats, and the ratio of beta(3)-adrenoceptors to beta-actin in obese SHRSP rats was lower than in lean littermates. These results indicate that the single-tube method can provide results equivalent to those from general real-time RTPCR methods in gene expression analysis.