Technical note: Selecting the best references in gene expression experiments in liver of cows receiving glucogenic supplements during the transition period.

Measuring gene expression is a commonly used method to monitor the reaction of cells and tissues to changing nutritional or physiological conditions. Selection of appropriate reference genes is a crucial point in gene expression experiments using real-time PCR techniques. Expression of the "ideal" reference gene should not be affected by the experimental treatments or physiological state of the tissue, organ, or the whole organism. Many programs are available from which to choose the most stable reference gene. In this study, 4 algorithms--ΔCt, BestKeeper, NormFinder, and geNorm--were used to assess the expression stability of 5 candidate reference genes: ß-actin (ACTB), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), ribosomal protein S9 (RPS9), ribosomal protein L32 (RPL32), and TATA-box-binding protein (TBP), for use in an experiment aimed at measuring gene expression in the liver of cows fed glucogenic supplements in the transition from pregnancy to lactation. The results demonstrated that RPS9 and RPL32 were the most stably expressed in the liver under the conditions of the present experiment; the least stably expressed was ACTB.

Allelic gene expression imbalance of bovine IGF2, LEP and CCL2 genes in liver, kidney and pituitary.

Allelic expression imbalance (AEI) is an important genetic factor being the cause of differences in phenotypic traits that can be heritable. Studying AEI can be useful in searching for factors that modulate gene expression and help to understand molecular mechanisms underlying phenotypic changes. Although it was commonly recognized in many species and we know many genes show allelic expression imbalance, this phenomena was not studied on a larger scale in cattle. Using the pyrosequencing method we analyzed a set of 29 bovine genes in order to find those that have preferential allelic expression. The study was conducted in three tissues: liver, pituitary and kindey. Out of the studied group of genes 3 of them-LEP (leptin), IGF2 (insulin-like growth factor 2), CCL2 (chemokine C-C motif ligand 2) showed allelic expression imbalance.

Assessment of aprotinin influence on periodontal clinical status and matrix metalloproteinases 1, 2 and their tissue inhibitors saliva concentrations in patients with chronic periodontitis.

PURPOSE: Assessment of the effect of treatment with aprotinin-containing drug on the clinical status of the periodontal tissue and on the concentrations of metalloproteinases released in the course of periodontitis (MMP-1, MMP-2) as well as their tissue inhibitors (TIMP-1 and TIMP-2) in the saliva of patients with chronic periodontitis (CP). MATERIAL/METHODS: The study involved 25 subjects with CP (39-68 years), including 16 women and 9 men. The patients were prescribed aprotinin preparation to be taken for 2 weeks. The control group (C) involved 14 healthy subjects (41-65 years), including 10 women and 4 men. Two periodontal indices were assessed: the approximal plaque index (API) and bleeding on probing index (BOP). Periodontal pocket depth and clinical attachment level were also evaluated. The concentrations of MMP-1 and MMP-2 as well as TIMP-1 and TIMP-2 were determined by the ELISA method. RESULTS: The mean salivary MMP-1 concentration in patients with CP was significantly higher before and after treatment, as compared to healthy subjects. The mean salivary MMP-2 concentration in CP patients at baseline was also higher as compared to the C group and increased after treatment. The mean salivary TIMP-1 and TIMP-2 concentration in CP patients was higher as compared to C group and increased after treatment. CONCLUSIONS: Since the mean MMPs levels were found to be growing it can be assumed that aprotinin has no significant effect on the regulation of MMPs in the saliva of CP patients. It thus seems that aprotinin application after scaling has no additional therapeutic effect.