No abstract

Human adenoviruses have been used to develop candidate HIV vaccine vectors, but a major obstacle to the use of vectors derived from Ad5 and other common serotypes is the high prevalence of neutralizing antibodies (NAbs) in humans. Prior studies have reported a prevalence of Ad5 between 60% and 70% in Europe and US, and up to 98% in surveyed African and Asian (Thai) tropical countries. However, few studies have reported on the Ad5 prevalence in Chinese populations. In this study, a total of 1,250 healthy adult serum samples from six administratively separate regions of China were screened by high-throughput luciferase-based virus neutralization assays. Results showed that overall 72% of healthy adults were Ad5 seropositive, and 46.4% with baseline Ad5 NAb titers of >200 in China. Comprehensive analysis by geographical region and age showed that the seroprevalence of Ad5 in southern China such as Guangxi was higher than that in other regions. Geographical differences and climate were considered as the major factors affecting the titer levels of Ad5 in healthy adults. In addition, no apparent gender and ethnic difference was found in any group classified according to region, age, or NAb titer. The present study may provide useful insights for the future development of Ad5-based vaccines and gene therapy.

Valproic acid (VPA), a histone deacetylase inbibitor, has been shown to generate inducible pluripotent stem (iPS) cells from mouse and human fibroblasts with a significant higher efficiency. Because successful cloning by somatic cell nuclear transfer (SCNT) undergoes a full reprogramming process in which the epigenetic state of a differentiated donor nuclear is converted into an embryonic totipotent state, we speculated that VPA would be useful in promoting cloning efficiency. Therefore, in the present study, we examined whether VPA can promote the developmental competence of SCNT embryos by improving the reprogramming state of donor nucleus. Here we report that 1 mM VPA for 14 to 16 h following activation significantly increased the rate of blastocyst formation of porcine SCNT embryos constructed from Landrace fetal fibroblast cells compared to the control (31.8 vs. 11.4%). However, we found that the acetylation level of Histone H3 lysine 14 and Histone H4 lysine 5 and expression level of Oct4, Sox2, and Klf4 was not significantly changed between VPA-treated and -untreated groups at the blastocyst stage. The SCNT embryos were transferred to 38 surrogates, and the cloning efficiency in the treated group was significantly improved compared with the control group. Taken together, we have demonstrated that VPA can improve both in vitro and in vivo development competence of porcine SCNT embryos.

No abstract

Contamination of feed with zearalenone (ZEN) presents a significant risk to animal health. Here, a visible, rapid, and cost-effective aptamer-based method is described for the detection of ZEN. After 8 rounds of SELEX (systematic evolution of ligands by exponential enrichment) with an affinity-based monitor and counter-screening process, the ssDNA aptamer Z100 was obtained, which had high affinity (dissociation constant = 15.2 ± 3.4 nM) and good specificity. Docking analysis of Z100 indicated that noncovalent bonds (π–π interactions, hydrogen bonds, and hydrophobic interactions) helped ZEN to anchor in the binding sites. Finally, a label-free detection method based on gold nanoparticles and Z100 at 0.25 μM was developed for ZEN determination. Excellent linearity was achieved, and the lowest detection limit was 12.5 nM. This rapid and simple method for ZEN analysis has high sensitivity and can be applied for on-site detection of ZEN in animal feeds.