Silencing and Un-silencing of Tetracycline-Controlled Genes in Neurons

To identify the underlying reason for the controversial performance of tetracycline (Tet)-controlled regulated gene expression in mammalian neurons, we investigated each of the three components that comprise the Tet inducible systems, namely tetracyclines as inducers, tetracycline-transactivator (tTA) and reverse tTA (rtTA), and tTA-responsive promoters (Ptets). We have discovered that stably integrated Ptet becomes functionally silenced in the majority of neurons when it is inactive during development. Ptet silencing can be avoided when it is either not integrated in the genome or stably-integrated with basal activity. Moreover, long-term, high transactivator levels in neurons can often overcome integration-induced Ptet gene silencing, possibly by inducing promoter accessibility

Effect of non-encapsulated and encapsulated active dried yeast on blood cell count, blood metabolites and immune response of finishing beef heifers

A study was conducted to evaluate whether encapsulated active dried yeast (EDY), compared with non-protected (ADY) or antibiotics (ANT), improved immune response and blood metabolites of finishing beef heifers. Blood urea nitrogen was lower (P ˂ 0.05) with supplemented ADY and mixture of ADY and EDY (MDY) compared with control. Supplementation of MDY mixture also resulted in lower (P ˂ 0.05) red blood cell distribution width than control. Lipopolysaccharide binding protein was less (P ˂ 0.05) for EDY than control, ANT and ADY as well as cytokine concentration of interleukin-6 was less (P ˂ 0.05) for MDY versus control.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Effect of mixed live yeast and lactic acid bacteria on in vitro fermentation with varying media pH using a high-grain or high-forage diet

Two experiments were conducted to assess the effects of media pH and mixtures (SCEF) of live yeast (Saccharomyces cerevisiae; SC) and lactic acid bacteria (Enterococcus faecium; EF) on gas production (GP), dry matter disappearance (DMD) and volatile fatty acid (VFA) concentrations in batch culture using either high-forage (HF) or high-grain (HG) diets. Diets were evaluated in separate experiments, each as a complete randomized design with 2 (media pH, 5.8 and 6.5) 5 (control, 3 SCEF, monensin) factorial arrangement of treatments. The SCEF had varying ratios of SC:EF: 0:0 (control), 1.18:1 (SCEF1), 1.25:1 (SCEF2) and 1.32:1 (SCEF3), added on a log10 basis. For the HF diet, supplementation of SCEF had greater GP (P = 0.03) at pH 6.5, and greater DMD (P = 0.03) and VFA concentration (PThe accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author