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Background and purpose It is essential to diagnose ischaemic stroke as soon as possible after symptom onset, so that thrombolytic treatment can be initiated as quickly as possible. This might be greatly facilitated if cerebral CT could be carried out in a pre-hospital setting. The aim of this study was to evaluate if anaesthesiologists, who in Norway provide pre-hospital medical care, could be trained to assess cerebral CT scans to exclude radiological contraindications for thrombolytic stroke treatment. Methods Thirteen anaesthesiologists attended an 8-h course in acute stroke assessment, including a 2-h introduction to the neuroradiology of acute stroke. Each participant then assessed 12 non-contrast cerebral CT examinations of acute stroke patients with specific regard to radiological contraindications for thrombolytic therapy. Test results were compared with those of three experienced neuroradiologists. Inter-rater agreement between anaesthesiologists and neuroradiologists was calculated using Cohen's Kappa statistics. Robustness of the results was assessed using the non-parametric bootstrap. Results Among the neuroradiologists, Kappa was 1 for detecting radiological contraindications for thrombolytic therapy. Twelve of the 13 anaesthesiologists showed good or excellent agreement (Kappa > 0.60) with the neuroradiologists. The anaesthesiologists spent a median time of 2 min and 18 s on each CT scan. Conclusions This study suggests that anaesthesiologists who are experienced in pre-hospital care may be quickly trained to assess cerebral CT examinations in acute stroke patients with regard to radiological contraindications for thrombolytic therapy. [ABSTRACT FROM AUTHOR]

Summary Reproductive performance is a critical trait in dairy cattle. Poor reproductive performance leads to prolonged calving intervals, higher culling rates and extra expenses related to multiple inseminations, veterinary treatments and replacements. Genetic gain for improved reproduction through traditional selection is often slow because of low heritability and negative correlations with production traits. Detection of DNA markers associated with improved reproductive performance through genome-wide association studies could lead to genetic gain that is more balanced between fertility and production. Norwegian Red cattle are well suited for such studies, as very large numbers of detailed reproduction records are available. We conducted a genome-wide association study for non-return rate, fertility treatments and retained placenta using almost 1 million records on these traits and 17 343 genome-wide single-nucleotide polymorphisms. Genotyping costs were minimized by genotyping the sires of the cows recorded and by using daughter averages as phenotypes. The genotyped sires were assigned to either a discovery or a validation population. Associations were only considered to be validated if they were significant in both groups. Strong associations were found and validated on chromosomes 1, 5, 8, 9, 11 and 12. Several of these were highly supported by findings in other studies. The most important result was an association for non-return rate in heifers in a region of BTA12 where several associations for milk production traits have previously been found. Subsequent fine-mapping verified the presence of a quantitative trait loci (QTL) having opposing effects on non-return rate and milk production at 18 Mb. The other reproduction QTL did not have pleiotropic effects on milk production, and these are therefore of considerable interest for use in marker-assisted selection. [ABSTRACT FROM AUTHOR]

Boar taint is characterized by an unpleasant taste or odor in intact male pigs and is primarily attributed to increased concentrations of androstenone and skatole and to a lesser extent by increased indole. The boar taint compounds skatole and indole are produced by gut bacteria, metabolized in the liver, and stored in the fat tissue. Androstenone, on the other hand, is synthesized in the testis along with testosterone and estrogens, which are known to be important factors affecting fertility. The main goal of this study was to investigate the relationship between genetic factors involved in the primary boar taint compounds in an attempt to discover ways to reduce boar taint without decreasing fertility-related compounds. Hentabilities and genetic correlations between traits were estimated for compounds related to boar taint (androstenone, skatole, indole) and reproduction (testosterone, 1713-estradiol, and estrone sulfate). Heritabilities in the range of 0.47 to 0.67 were detected for androstenone concentrations in both fat and plasma, whereas those for skatole and indole were slightly less (0.27 to 0.41). The genetic correlations between androstenone in plasma and fat were extremely high (0.91 to 0.98) in Duroc and Landrace. In addition, genetic correlations between androstenone (both plasma and fat) and the other sex steroids (estrone sulfate, 173-estradiol, and testosterone) were very high, in the range of 0.80 to 0.95. Furthermore, a genome-wide association study (GWA) and a combined linkage disequilibrium and linkage analysis (LDLA) were conducted on 1,533 purebred Landrace and 1,027 purebred Duroc to find genome regions involved in genetic control of the boar taint compounds androstenone, skatole, and indole, and sex hormones related to fertility traits. Up to 3,297 informative SNP markers were included for both breeds, including SNP from several boar taint candidate genes. From the OWA study, we found that altogether 27 regions were significant at a genome-wide level (P < 0.05) and an aclditional 7 regions were significant at a chromosomal level. From the LDLA study, 7 regions were significant on a genome-wide level and an additional 7 regions were significant at a chromosomal level. The most convincing associations were obtained in 6 regions affecting skatole and indole in fat on chromosomes 1, 2, 3, 7, 13, and 14, 1 region on chromosome 6 affecting androstenone in plasma only, and 5 regions on chromosomes 3, 4, 13, and 15 affecting androstenone, testosterone, and estrogens. [ABSTRACT FROM AUTHOR]

Dystocia and stillbirth are significant causes of female and neonatal death in many species and there is evidence for a genetic component to both traits. Identifying causal mutations affecting these traits through genome wide association studies could reveal the genetic pathways involved and will be a step towards targeted interventions. Norwegian Red cattle are an ideal model breed for such studies as very large numbers of records are available. We conducted a genome wide association study for direct and maternal effects of dystocia and stillbirth using almost 1 million records of these traits. Genotyping costs were minimized by genotyping the sires of the recorded cows, and using daughter averages as phenotypes. A dense marker map containing 17 343 single nucleotide polymorphisms covering all autosomal chromosomes was utilized. The genotyped sires were assigned to one of two groups in an attempt to ensure independence between the groups. Associations were only considered validated if they occurred in both groups. Strong associations were found and validated on chromosomes 4, 5, 6, 9, 12, 20, 22 and 28. The QTL region on chromosome 6 was refined using LDLA analysis. The results showed that this chromosome most probably contains two QTL for direct effect on dystocia and one for direct effect on stillbirth. Several candidate genes may be identified close to these QTL. Of these, a cluster of genes expected to affect bone and cartilage formation (i.e. SPP1, IBSP and MEPE) are of particular interest and we suggest that these genes are screened in candidate gene studies for dystocia and stillbirth in cattle as well as other species. [ABSTRACT FROM AUTHOR]

Quantitative trait loci affecting clinical mastitis were detected and fine mapped to a narrow region on bovine chromosome 6 in the Norwegian Red cattle population. The region includes the casein gene cluster and several candidate genes thought to influence clinical mastitis. The most significant results were found for SNPs within the Mucin 7 gene. This gene encodes an antimicrobial peptide and constitutes part of the first line of defence for the mucosal immune system. Detection of long haplotypes extending several Mb may indicate that artificial selection has influenced the haplotype structures in the region. A search for selection sweeps supports this observation and coincides with association results found both by single SNP and haplotype analyses. Our analyses identified haplotypes carrying quantitative trait loci alleles associated with high protein yield and simultaneously fewer incidences of clinical mastitis. The fact that such haplotypes are found in relative high frequencies in Norwegian Red may reflect the combined breeding goal that is characterized by selection for both milk production and disease resistance. The identification of these haplotypes raises the possibility of overcoming the unfavourable genetic correlation between these traits through haplotype-assisted selection. [ABSTRACT FROM AUTHOR]

Purpose: Intra-arterial digital subtraction angiography (DSA) has been considered the gold standard examination in the follow-up of patients treated with Guglielmi detachable coils (GDCs). However, DSA is an invasive and expensive investigation and results in exposure to ionising radiation to both patient and operator. The aim of this study was to compare MR angiography (MRA) with DSA with regard to patency of the occlusion of aneurysms following GDC treatment.Material and Methods: We performed 75 MRA and DSA examinations on 51 patients treated with GDCs. The examinations were performed 3-36 months after embolisation and the interval between MRA and DSA was less than 1 week. Hard copies of both studies were interpreted retrospectively and independently for residual flow within the aneurysm, residual aneurysmal neck, and parent and branch vessel flow.Results: Patency status of parent and branch vessel flow was correctly identified with MRA in all patients except 1. The sensitivity of MRA in revealing residual flow within the aneurysm was 97%. The specificity in ruling out residual flow within the aneurysm was 91%.Conclusion: MRA may replace DSA in the long-term follow-up of coiled cerebral aneurysms. The initial follow-up examination should, however, include both modalities. [ABSTRACT FROM AUTHOR]