Analysis of authorized coccidiostats in chicken feces and environmental water by ultra-performance liquid chromatography-tandem mass spectrometry based on dispersive solid-phase extraction and lyophilization.

A simple, sensitive, and efficient method based on ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the determination of 8 coccidiostats in chicken feces and environmental water (including sewage, pond water, and lake water) surrounding the farm. Target analytes in chicken feces were extracted with 2% acetic acid in acetonitrile solution, followed by a dispersive solid-phase extraction (DSPE) cleanup step using the mixture of PSA and C18 adsorbents. Environmental water samples were pretreated using a lyophilization approach. Analysis was carried out on a UPLC-MS/MS with the combination of methanol and 0.1% formic acid aqueous solution as the mobile phase under multiple reaction monitoring in positive and negative ionization modes. Results showed that 8 coccidiostats were linear with correlation coefficients higher than 0.99. Method validation was performed using fortified samples, reaching satisfactory recoveries of 75.9%-97.8% in chicken feces and 71.9%-108.2% in environmental water. Limits of detection for 8 analytes in chicken feces and environmental water were 0.03∼2 µg/kg and 0.005∼1 µg/L, respectively. Matrix effects were calculated and strong signal suppression (>50%) for some coccidiostats was observed. The developed method was successfully applied to analyze coccidiostats in chicken feces and environmental water collected from local chicken farms.

Response Surface Optimization of Dispersive Solid-Phase Extraction Combined with HPLC for the Rapid Analysis of Multiple Coccidiostats in Feed.

Since antimicrobials were banned as feed additives, coccidiostats with favorable anticoccidial action and growth promotion have been widely used in the breeding industry. The monitoring of coccidiostats in feed is necessary, while the current methods based on mass-spectrometer analysis have limited applicability and matrix effects could interfere with the results. Accordingly, in the present paper, a rapid analytical strategy for the simultaneous determination of six synthetic coccidiostats in feed using high-performance liquid chromatography coupled with diode-array detection was developed. Coccidiostats in chicken feeds were extracted with the trichloroacetic acid-acetonitrile solution. The cleanup was performed by dispersive solid-phase extraction after the optimization of the response surface methodology. The method exhibited good linearity for target coccidiostats within the range of 0.05~20 µg/mL. Recoveries for six compounds in fortified feed samples were from 67.2% to 107.2% with relative standard deviations less than 9.6%. The limit of detection was 0.2~0.3 mg/kg. The successful application of the method in commercial feed verified that it is effective and sensitive for the rapid determination of multiple coccidiostats in chicken feeds.

De Novo Human Cardiac Myocytes for Medical Research: Promises and Challenges.

The advent of cellular reprogramming technology has revolutionized biomedical research. De novo human cardiac myocytes can now be obtained from direct reprogramming of somatic cells (such as fibroblasts), from induced pluripotent stem cells (iPSCs, which are reprogrammed from somatic cells), and from human embryonic stem cells (hESCs). Such de novo human cardiac myocytes hold great promise for in vitro disease modeling and drug screening and in vivo cell therapy of heart disease. Here, we review the technique advancements for generating de novo human cardiac myocytes. We also discuss several challenges for the use of such cells in research and regenerative medicine, such as the immature phenotype and heterogeneity of de novo cardiac myocytes obtained with existing protocols. We focus on the recent advancements in addressing such challenges.

CDKN2BAS polymorphisms are associated with coronary heart disease risk a Han Chinese population.

The goal of our study was to determine whether CDKN2BAS polymorphisms are associated with coronary heart disease (CHD) risk in a Han Chinese population. Eight SNPs were genotyped in 676 men and 465 women. We used χ2 tests and genetic model analyses to evaluate associations between the SNPs and CHD risk. We found that rs10757274 was associated with an increased risk of CHD in both men (allele G: Odds ratio [OR] = 1.30, 95% confidence interval [CI]: 1.05-1.61, P = 0.018; codominant model: P = 0.042; recessive model: OR = 1.70, 95% CI: 1.10-2.62, P = 0.016; log-additive model: OR = 1.34, 95% CI: 1.05-1.71, P = 0.019) and women (dominant model: OR = 2.26, 95% CI: 1.28-3.99, P = 0.004). In addition, rs7865618 was associated with an 8.10-fold increased risk of CHD in women under a recessive model (OR = 8.10, 95% CI: 1.74-37.68, P = 0.006). Interestingly, the haplotype AA (rs10757274 and rs1333042) of CDKN2BAS was associated with decreased the risk of CHD in men (OR = 0.72, 95% CI: 0.55 - 0.95, P = 0.022).