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In reaction to central control of schooling by the Soviet Union, the Czech Republic countered with what some say was the most decentralized system in Europe. While the political move to democracy was extraordinarily successful, there were numerous governments between 1989 and the present. The combination of the decentralized control of schooling and lack of continuity in the political realm in regard to education lengthened substantially the amount of time it has taken to mount national assessments. Those assessments, 5th and 9th grade and a high school leaving examination, are now on track but not without political and technical barriers.

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Constitutive androstane receptor (CAR) is a nuclear receptor that regulates genes involved in detoxification and elimination of potentially toxic foreign and endogenous compounds (xenobiotics and endobiotics). In addition, CAR also regulates genes involved in energy homeostasis, affecting such processes as thyroid hormone metabolism and gluconeogenesis. The constitutive activity and specificity of ligand binding are dependent upon highly conserved amino acids involved in hydrogen bonding that maintain the activated conformation of the CAR molecule. Specifically, computer modeling has shown that a central tyrosine (Y326) is required for maintenance of the activated conformation, likely through the formation of a hydrogen bond with an asparagine (N165) on the opposite side of the ligand binding domain. Site directed mutagenesis studies have confirmed this prediction. While these residues are highly conserved across mammalian species, we have discovered that ruminant species possess hydrophobic amino acids in these locations that would preclude hydrogen bond formation. In particular, CAR sequences obtained thus far from all ruminant species using multiple individual and pooled DNA samples from several breeds of cattle, as well as individual samples from sheep, red deer, wapiti, roe deer, goat and bison, all possess a phenylalanine substitution at the critical tyrosine residue (Y326F). Interestingly, the Bovidae (Bos taurus, Bos indicus, Bison bison) also have a substitution in the partner amino acid residue asparagine, N165, that is replaced by the hydrophobic residue isoleucine. These changes are not observed in non-ruminant herbivores. Given the importance of CAR as a repressor of hepatic genes encoding gluconeogenic enzymes, and the critical requirement in ruminant species for very high rates of glucose production, the ruminant CAR variants may play a vital role in the regulation of gluconeogenesis. [ABSTRACT FROM AUTHOR]

The primary causes of off-odors in pork from uncastrated male pigs, a phenomenon commonly known as "boar taint", are the presence of pheromonal androstene steroids as well as skatole and indole in adipose tissue. The latter compounds are products of microbial tryptophan metabolism. Hepatic cytochromes p450 (CYP) catalyze diverse reactions that are involved in the metabolism of compounds that cause boar taint. Constitutive androstane receptor (CAR) is a nuclear receptor (NR) known to regulate transcription of many hepatic genes including CYP genes. The objective of this investigation was to determine whether CAR mRNA expression is related to expression of hepatic CYPs and associated with concentrations of boar taint compounds. Liver samples from market weight pigs were collected at slaughter and total RNA extracted from 18 intact males and 8 castrates. Real-time reverse-transcription polymerase chain reaction (RT-PCR) was performed to quantify relative mRNA abundance for NR and selected target genes. Concentrations of androstenone, skatole and indole in backfat were determined by HPLC. Hepatic expression of CAR was positively correlated (P < 0.05) with mRNA expression of PXR (pregnane X receptor), CYP2E1, CYP2A6, CYP1A2, and uridine glucuronosyl transferase 1A1 (UGT1A1). CAR mRNA abundance was negatively correlated with skatole (r = -0.41; P < 0.05) and indole (r = -0.64; P < 0.01); CYP2B22 mRNA abundance was negatively correlated (P < 0.05) with indole (r = -0.49; P < 0.05) concentrations in backfat. Abundance of PXR mRNA was negatively correlated with indole concentrations (r = -0.41; P < 0.05), but was not associated with skatole level in backfat (P > 0.10). These results suggest that CAR plays an important role in regulating transcription of hepatic genes involved in metabolism of compounds that cause boar taint in intact male pigs. [ABSTRACT FROM AUTHOR]

The significance of paracrine, autocrine, and intracrine endocrine signaling for optimal growth and differentiation of mammary tissue is well known. According to previous reports, a unique form of Lf mRNA, termed delta-lactoferrin (Δ-Lf) has been detected in human tissues and cell lines (Δ-hLf). Our objective was to determine if Δ-bovine Lf (Δ-bLf ) is expressed in bovine mammary tissue. Our earlier work indicated that bLf appears in the nucleus and affects retinoid signaling in mammary cells in vitro. Furthermore, in vivo experiments using transgenic mice that over-express mammary hLf indicated a Lf:retinoid interaction that perturbed lactation. Δ-hLf mRNA is reported to be identical to Lf except that exon 1 is modified such that a signal sequence is deleted. Because Lf has a nuclear localization sequence, loss of a signal sequence would direct a cytoplasmic protein and subsequent nuclear location. The presence of Δ-bLf mRNA expression in bovine tissue was explored by using bovine mammary cells; BME-UV and primary bovine mammary cells as well as controls with human mammary cells. While BME-UV and the human cell lines make little or no Lf mRNA, the primary bovine cells exhibit high expression that could be modified by culture with hormones. Primers reported for human Δ-Lf were used for human mammary cell extracts and were used as templates to design bovinespecific primers. No evidence of Δ-Lf mRNA was identified in any of the cell extracts of either species with any primer sets. Bioinformatics searches of TIGR, Ensembl, and NCBI expressed sequence tags (ESTs) for presence of Δ-bLf (bLf with different message length) in the bovine data base were negative. Similar searches of the human EST data base for Δ -hLf produced little evidence for the presence of the message save the submitted Δ-Lf sequence and several rare transcripts that did not indicate a differential mRNA expression of Δ-hLf. The presence and perhaps the significance of Δ-bLf in bovine mammary tissue is unresolved. [ABSTRACT FROM AUTHOR]

Background: It is known that many anti-Wr(a) antibodies are not detected, because of the lack of Wr(a) positive test cells in antibody screening and identification panels. After a severe hemolytic transfusion reaction caused by anti-Wr(a) in a patient with stomach cancer, this study evaluates the rate of anti-Wr(a) in blood donors in southwestern Germany. Methods: Routine antibody screening test was performed in 22,697 blood donors using a solid phase antiglobulin test with a 2-cell panel (Solidscreen II, Biotest, Germany) and an additional Wr(a) positive test cell. The antibody specificity of the positive samples was determined in the gel test (DiaMed ID, LISS-Coombs) using a 14-cell identification panel including 3 different Wr(a) positive test cells. Results: The following 487 antibodies were found (please refer to the table below). The average age of the donors with anti-Wr(a) was 44 years for men and 43 years for women. It was the same as the average age of the entire tested population. The rate of anti-Wr(a) was 1.33% in men and 2.36% in women, which means that the rate in women was 1.78 times higher than in men. Conclusions: Anti-Wr(a) is the most common red cell antibody in blood donors in southwestern Germany. It is more frequent than the sum of all other detected antibodies and about 10 times more frequent than anti-D. As it is clinically significant, screening panels should contain a Wr(a) positive test cell, especially when using type and screen in pretransfusion management only. [ABSTRACT FROM AUTHOR]

Nuclear receptors (NR), including retinoic acid and retinoid X receptors (RAR, RXR), pregnane X receptor (PXR), constitutive androstane receptor, and peroxisome proliferator-activated receptor (PPARα) modify the expression of other genes, such as cytochrome p450 enzymes (CYP), sulfotransferases (SULT), and UDP glucuronosyl transferases (UGT). Nuclear receptor expression is influenced by exposure to ligands (e.g., vitamin A). We tested the hypothesis that vitamin A feeding influences the expression of hepatic and intestinal NR and their target genes and that colostrum or formula feeding influence these traits differently. Calves (n = 7/ group) were fed colostrum (CO) or a milk-based formula with or without vitamin A (FA, FO, respectively) for 4 d and were euthanized on d 5, followed immediately by tissue collection. Thereafter, RNA was extracted and gene expression quantified by real-time reverse transcription-polymerase chain reaction. Expression relative to housekeeping genes of mRNA was profiled for NR, CYP, SULT, and UGT enzymes. Hepatic mRNA levels of RARβ and CYP26 were higher in FA than FO cows; expression of CYP2E1, CYP2C8, CYP26, and UGT1A1 was higher in CO than FO cows; and expression of CYP2E1, UGT1A1, and p450 reductase was higher in CO than FA. In colon tissue, abundance of RXRα mRNA was lower in FO than CO, and CYP2B6 expression was lower in FO than in CO and FA. In jejunal tissue, there were no significant differences in gene expression among groups. In conclusion, effects of vitamin A feeding were limited, but colostrum feeding had several selective effects on expression of nuclear receptors and target genes. [ABSTRACT FROM AUTHOR]

Milk replacer was supplemented with nucleotides and fed to dairy calves from birth through weaning to examine the potential for enhancing recovery of small intestinal function after enteric infection. Three treatments of 23 calves each were fed milk replacer (10% body weight/d) supplemented with no nucleotides (C), purified nucleotides (N), or nucleotides from an extract of Saccharomyces cerevisiae (S). Average daily gain, health scores, fecal dry matter, and fecal bacteria were monitored, and blood was analyzed for packed cell volume, glucose, blood urea nitrogen (BUN), and creatinine. Calves were monitored twice daily for fecal score, and 48 h after increased fecal fluidity was recorded, intestinal function was evaluated by measuring absorption of orally administered xylose (0.5 g/kg of body weight). Packed cell volume of blood was greater for treatment N for wk 2 and 5 compared with other treatment groups. Four calves per treatment were killed, and intestinal tissue was evaluated for morphology, enzyme activities, and nucleoside transporter mRNA expression. Treatment S calves had increased abundance of nucleoside transporter mRNA, numerically longer villi, and lower alkaline phosphatase than other groups. Growth measurements and plasma concentrations of glucose, BUN, creatinine, and IgG were not different between treatments; however, BUN-to-creatinine ratio was higher for treatment N, possibly indicating decreased kidney function. There were also no treatment effects on fecal dry matter and fecal bacteria population. However, N-treated calves had the highest detrimental and lowest beneficial bacteria overall, indicating an unfavorable intestinal environment. Supplementation of purified nucleotides did not improve intestinal morphology or function and resulted in higher fecal water loss and calf dehydration. Supplementation of nucleotides derived from yeast tended to increase calf intestinal function, provide a more beneficial intestinal environment, and improve intestinal morphology. [ABSTRACT FROM AUTHOR]

Introduction: A smooth transition to primary school is positively related to children's later school experience. Certain parental school-readiness beliefs and parenting styles, among other factors, contribute to the smoothness of this transition., Methods: Therefore, this study adopted a latent profile analysis to examine the patterns of Chinese parents' school-readiness beliefs and their parenting styles and investigated socioeconomic status (SES) differentials in both. Two-stage probability sampling method is adopted in this study and a total of 1,204 Chinese parents of 5- to 6 years-old children were investigated with school-readiness beliefs scale, Parenting Styles and Dimensions Questionnaire, as well as scale of attitudes regarding roles in school readiness All data analyses were processed in Mplus 8.6., Results and Discussion: Three profiles were identified: (1) supportive parenting with a very strong emphasis on school readiness; (2) partially supportive parenting with a reflection of school readiness; (3) weakly supportive parenting with no emphasis on school readiness. Higher SES was found to be more likely to be associated with membership in Profile 1 rather than Profile 2. The present study shows quantitative support for Anette Lareau's work and has implications for the development of more targeted parental intervention programs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Cui and Greger.)

Because negative findings have less chance of getting published, available studies tend to be a biased sample. This leads to an inflation of effect size estimates to an unknown degree. To see how meta-analyses in education account for publication bias, we surveyed all meta-analyses published in the last five years in the Review of Educational Research and Educational Research Review. The results show that meta-analyses usually neglect publication bias adjustment. In the minority of meta-analyses adjusting for bias, mostly non-principled adjustment methods were used, and only rarely were the conclusions based on corrected estimates, rendering the adjustment inconsequential. It is argued that appropriate state-of-the-art adjustment (e.g., selection models) should be attempted by default, yet one needs to take into account the uncertainty inherent in any meta-analytic inference under bias. We conclude by providing practical recommendations on dealing with publication bias., Competing Interests: The authors have declared that no competing interests exist.