Identification of polymorphisms in the ovine Shadow of prion protein (SPRN) gene and assessment of their effect on promoter activity and susceptibility for classical scrapie.

Shadow of prion protein (SPRN) is an interesting candidate gene thought to be involved in prion pathogenesis. In humans, an association has already been discovered between mutations in SPRN and the incidence of variant and sporadic Creutzfeldt-Jakob disease. However, in sheep, the effect of mutations in SPRN is largely unknown. Therefore, we analysed the presence of mutations in the entire ovine SPRN gene, their association with scrapie susceptibility and their effect on SPRN promoter activity. In total, 26 mutations were found: seven in the promoter region, four in intron 1, seven in the coding sequence and eight in the 3' untranslated region. The mutations detected in the coding sequence and the promoter region were subsequently analysed in more detail. In the coding sequence, a polymorphism causing a deletion of two alanines was found to be associated with susceptibility for classical scrapie in sheep. Furthermore, a functional analysis of deletion constructs of the ovine SPRN promoter revealed that the region 464 to 230 bp upstream of exon 1 (containing a putative AP-2 and putative Sp1 binding sites) is of functional importance for SPRN transcription. Six mutations in the SPRN promoter were also found to alter the promoter activity in vitro. However, no association between any of these promoter mutations and susceptibility for classical scrapie was found.

Correlation between porcine PPARGC1A mRNA expression and its downstream target genes in backfat and longissimus dorsi muscle.

Knowledge of in vivo relationship between the coactivator PPARGC1A and its target genes is very limited, especially in the pig. In this study, a real-time PCR experiment was performed on longissimus dorsi muscle (MLD) and backfat with 10 presumed PPARGC1A downstream target genes, involved in energy and fat metabolism, to identify possible relationships with PPARGC1A mRNA expression in vivo in the pig (n = 20). Except for UCP3 and LPL, a very significant difference in expression was found between MLD and backfat for all genes (P < 0.01). Hierarchical cluster analysis and the significant pairing of mRNA expression data between sampling locations suggested a genetic regulation of the expression of several target genes. A positive correlation with PPARGC1A was found for CPT1B, GLUT4, PDK4, and TFAM (P < 0.0001). A negative correlation was found for UCP2, FABP4, LEP (P < 0.0001), and TNF (P = 0.0071). No significant correlation was detected for UCP3 and LPL. This study provides evidence for a clear difference in mRNA expression of crucial genes in fat and energy metabolism between 2 important tissues. Our data suggest a clear impact of PPARGC1A on energy and lipid metabolism in vivo in the pig, through several of these downstream target genes.

Association analyses of candidate single nucleotide polymorphisms on reproductive traits in swine.

The ability to identify young females with superior reproduction would have a large economic impact on commercial swine production. Previous studies have discovered SNP associated with economically important traits such as litter size, growth rate, and feed intake. The objective of this study was to test for association of candidate SNP with sow prolificacy reproductive traits in gilts of a Landrace-Duroc-Yorkshire composite population. Association analyses regressed additive (A), dominant (D), and imprinting (I) SNP effects on each trait with an animal model. A carnitine palmitoyltransferase 1A SNP and a glycogen synthase 1 SNP were associated with age at puberty (AP; D = 10 d; P = 0. 0037 and A = 3.8 d; P = 0.0078, respectively). Four IGF2 SNP were associated with AP as well, having additive or dominant effects (3.2 to 5.8 d; P < or = 0.0052). Two mannosidase 2B2 SNP and 2 prolactin receptor (PRLR) SNP were also associated with AP. Solute carrier 22, subfamily member 5 SNP was weakly associated with AP (D = 3.9 d; P < 0.10). Polymorphisms within glycogen synthase 1 and protein kinase AMP-activated, gamma 3 noncatalytic subunit had associations with ovulation rate. Estrogen receptor (ESR) 1, ESR2, PPAR gamma coactivator 1, and IGFBP3 SNP were significantly associated with weaning-to-estrus interval. Two PRLR SNP were associated with total number of piglets born (A = 0.57 piglets; P = 0.0095 and D = 0.61 piglets; P = 0.0016, respectively). A SNP within PRLR was also associated with number of piglets born alive (D = 0.61; P = 0.0016). The PPAR gamma coactivator 1 SNP was associated with total number of piglets born (D = 0.38 piglets; P = 0.0391) and number of piglets born alive (D = 0.53 piglets; P = 0.0032). The SNP within ESR1 (A = 0.65 piglets; P = 0.0950), ESR2 (A = -0.33 piglets; P = 0.0176), IGF2 SNP (A = -0.26 piglets; P = 0.0032), and IGFBP3 SNP (D = 0.35 piglets; P = 0.0683) were associated with number of piglets born dead. A leptin SNP was associated with mummified fetuses (D = 0.09 piglets; P = 0.0978). Many of the SNP analyzed in this study are from genes involved in regulation of metabolism, suggesting that there is an important link between physiological events associated with reproduction and energy utilization. Furthermore, these production and growth trait SNP may serve to assist in selection of young females for superior reproductive performance.

Confluent education: an integrative method for nursing (continuing) education.

Confluent education is presented as a method to bridge the gap between cognitive and affective learning. Attention is focused on three main characteristics of confluent education: (a) the integration of four overlapping domains in a learning process (readiness, the cognitive domain, the affective domain and responsibility); (b) the promotion of personal growth and interpersonal relationships by the development of awareness, and (c) the identification and dis-identification of teacher and participants. How confluent education can take place in practice is illustrated by presenting the way in which this method is applied in a nursing continuing education programme entitled 'Pain assessment and management in surgical-oncological patients'.