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Biomedical subjects

H Thomsen

Publications and source records attributed to H Thomsen.

At least 19 recordsLinked to original sources
PubMed2006

Photosynthetic responses to elevated CO(2) and O(3) in Quercus ilex leaves at a natural CO(2) spring.

Photosynthetic stimulation and stomatal conductance (Gs) depression in Quercus ilex leaves at a CO(2) spring suggested no down-regulation. The insensitivity of Gs to a CO(2) increase (from ambient 1500 to 2000 micromol mol(-1)) suggested stomatal acclimation. Both responses are likely adaptations to the special environment of CO(2) springs. At the CO(2)-enriched site, not at the control site, photosynthesis decreased 9% in leaves exposed to 2x ambient O(3) concentrations in branch enclosures, compared to controls in charcoal-filtered air. The stomatal density reduction at high CO(2) was one-third lower than the concomitant Gs reduction, so that the O(3) uptake per single stoma was lower than at ambient CO(2). No significant variation in monoterpene emission was measured. Higher trichome and mesophyll density were recorded at the CO(2)-enriched site, accounting for lower O(3) sensitivity. A long-term exposure to H(2)S, reflected by higher foliar S-content, and CO(2) might depress the antioxidant capacity of leaves close to the vent and increase their O(3) sensitivity.

Adaptation, Physiological↗
PubMed2006

Mapping of quantitative trait loci for lactation persistency traits in German Holstein dairy cattle.

A whole genome scan to map quantitative trait loci (QTL) for persistency of milk yield (PMY), persistency of fat yield (PFY), persistency of protein yield (PPY) and persistency of milk energy yield (PEY) was performed in a granddaughter design in the German Holstein dairy cattle population. The analysis included 16 paternal half-sib families with a total of 872 bulls. The analysis was carried out for the first lactation and for the first three lactations combined using univariate weighted multimarker regression. Controlling the false discovery rate across traits and data sets at a level of 0.15 and treating the four persistency traits as different traits revealed 27 significant QTL. A total of 12 chromosomes showed significant QTL effects on a chromosomewise basis. The DGAT1 effect was highly significant for PPY and protein yield. A haplotype analysis using results of previous studies of the same design revealed a co-segregation of various persistency QTL and QTL affecting health traits like dystocia and stillbirth and functional traits like non-return rate 90 and somatic cell score.

Animals↗
PubMed2004

Convalescence after inguinal herniorrhaphy.

BACKGROUND: Convalescence after inguinal herniorrhaphy is usually 3-4 weeks and is an important outcome parameter of hernia surgery. The aim of this study was to describe in detail the consequences of recommending a short convalescence, including the risk of recurrence. METHODS: This was a multicentre prospective questionnaire study in patients given a recommendation for short convalescence (1 day); information was recorded on expected length of convalescence, employment status, physical workload and limiting factors. The reoperation rate in patients included in the study (group 1, n = 1059) was compared with that for comparable patients treated in participating departments but not part of the study group (group 2, n = 1306) and patients in the Danish Hernia Database (group 3, n = 8297). RESULTS: The median time off work was 7 days and the time interval before carrying out the most strenuous leisure activity was 14 days. After 30 days, 6.8 per cent of patients had not resumed employment and 17.0 per cent had not yet resumed strenuous leisure activity. Important reasons for not resuming work and leisure activity were pain (approximately 60 per cent of patients) and wound problems (approximately 20 per cent). The reoperation rate in group 1 at the median observation time was 0.7 per cent, which was no different to that in group 2 (1.6 per cent) (P = 0.186) or group 3 (1.4 per cent) (P = 0.092). CONCLUSION: Reduced convalescence after inguinal herniorrhaphy may be recommended without incurring a risk of higher reoperation rates. Pain and wound problems remain the most important factors for not resuming work or leisure activity as recommended.

Adult↗
PubMed2004

Combined MR examination of prostate: is it reliable?

A combination of magnetic resonance (MR) methods (T2-weighted MRI, proton MR spectroscopy, and dynamic contrast enhancement) gives the highest sensitivity and specificity for identification of prostate cancer by MRI. The prostate MR findings of a patient with a congenital cystic disease of seminal vesicle are presented. To our knowledge, this is the only case described in the literature. The MR examination resulted in a false-positive indication of prostate cancer.

Adult↗
PubMed2004

New alleles in calpastatin gene are associated with meat quality traits in pigs.

Suggestive QTL affecting raw firmness scores and average Instron force, tenderness, juiciness, and chewiness on cooked meat were mapped to pig chromosome 2 using a three-generation intercross between Berkshire and Yorkshire pigs. Based on its function and location, the calpastatin (CAST) gene was considered to be a good candidate for the observed effects. Several missense and silent mutations were identified in CAST and haplotypes covering most of the coding region were constructed and used for association analyses with meat quality traits. Results demonstrated that one CAST haplotype was significantly associated with lower Instron force and cooking loss and higher juiciness and, therefore, this haplotype is associated with higher eating quality. Some of the sequence variation identified may be associated with differences in phosphorylation of CAST by adenosine cyclic 3', 5'-monophosphate-dependent protein kinase and may in turn explain the meat quality phenotypic differences. The beneficial haplotype was present in all the commercial breeds tested and may provide significant improvements for the pig industry and consumers because it can be used in marker-assisted selection to produce naturally tender and juicy pork without additional processing steps.

Alleles↗
PubMed2004

Characterization of quantitative trait loci for growth and meat quality in a cross between commercial breeds of swine.

A three-generation resource family was created by crossing two Berkshire grandsires with nine Yorkshire granddams to identify QTL affecting growth, body composition, and meat quality. A total of 512 F2 offspring were evaluated for 11 traits related to growth and body composition and 28 traits related to meat quality. All animals were initially genotyped for 125 markers across the genome. The objectives of this advanced phase of the project were to further identify and characterize QTL after genotyping for another 33 markers in special regions of interest, and to develop and apply methods for detecting QTL with parent-of-origin effects. New marker linkage maps were derived and used in QTL analysis based on line-cross least squares regression-interval mapping. A decision tree for identifying QTL with parent-of-origin effects was developed based on tests against the Mendelian mode of expression. Empirical significance thresholds were derived at chromosomewise and genomewise levels using specialized permutation strategies to create data under the null hypothesis appropriate for each test. Significance thresholds derived by the permutation tests were validated based on simulation of a pedigree and data structure similar to the Berkshire-Yorkshire population. The addition of 33 markers resulted in the discovery of 29 new QTL at the 5% chromosomewise level using the Mendelian model of analysis. Thirteen of the original QTL were no longer significant at the 5% chromosomewise level. A total of 33 QTL with parent-of-origin effects were identified, including QTL with paternal expression for backfat and loin muscle area on chromosome 2, near IGF2, and QTL with maternal expression for drip loss and reflectance on chromosome 9. Tests for imprinting against Mendelian expression identified much fewer QTL with parent-of-origin effects than tests based on significance of paternal and maternal alleles, which have been used in other studies. The detected QTL and their identified mode of expression will allow further research in these QTL regions and their utilization in marker-assisted improvement of meat quality.

Adipose Tissue↗
PubMed2004

The DGAT1 K232A mutation is not solely responsible for the milk production quantitative trait locus on the bovine chromosome 14.

The gene, acyl-CoA:diacylglycerol acyltransferase1 (DGAT1), was recently identified as the one underlying the quantitative trait locus (QTL) for milk production traits in the centromeric region of the bovine chromosome 14. Until now, 2 alleles, the lysine variant (increasing fat yield, fat and protein percentage) and the alanine variant (increasing protein and milk yield), were postulated at DGAT1. This study investigated whether the diallelic DGAT1 polymorphism is responsible for all the genetic variation at the centromeric region of this chromosome for milk, fat, and protein yield and fat and protein percentage. A statistical model was applied to a granddaughter design to analyze 16 German Holstein families. The model included the diallelic DGAT1 effect and the QTL transition probability estimated for each chromosomal position by a multiple marker approach. Because the regression coefficient of this probability was corrected for the diallelic DGAT1 polymorphism, it represented a putative conditional QTL effect. The effect of the DGAT1 gene was always highly significant. The conditional QTL effect was significant genomewise for fat percentage at the proximal end of the chromosome and for protein percentage at a more distal chromosomal region. Additional chromosomewise significance was found for fat and protein yield. Our results suggest an additional source of genetic variance on this chromosome for these traits; either one or more additional alleles segregating at DGAT1 that were not previously detected, a second quantitative trait locus affecting these traits, or both.

Acyltransferases↗
PubMed2003

Quantitative trait loci mapping of functional traits in the German Holstein cattle population.

A whole-genome scan to detect quantitative trait loci (QTL) for functional traits was performed in the German Holstein cattle population. For this purpose, 263 genetic markers across all autosomes and the pseudoautosomal region of the sex chromosomes were genotyped in 16 granddaughter-design families with 872 sons. The traits investigated were deregressed breedingvalues for maternal and direct effects on dystocia (DYSm, DYSd) and stillbirth (STIm, STId) as well as maternal and paternal effects on nonreturn rates of 90 d (NR90m, NR90p). Furthermore, deregressed breeding values for functional herd life (FHL) and daughter yield deviation for somatic cell count (SCC) were investigated. Weighted multimarker regression analyses across families and permutation tests were applied for the detection of QTL and the calculation of statistical significance. A ten percent genomewise significant QTL was localized for DYSm on chromosome 8 and for SCC on chromosome 18. A further 24 putative QTL exceeding the 5% chromosomewise threshold were detected. On chromosomes 7, 8, 10, 18, and X/Yps, coincidence of QTL for several traits was observed. Our results suggest that loci with influence on udder health may also contribute to genetic variance of longevity. Prior to implementation of these QTL in marker assisted selection programs for functional traits, information about direct and correlated effects of these QTL as well as fine mapping of their chromosomal positions is required.

Animals↗
PubMed2002

Mapping of the bovine blood group systems J, N', R', and Z show evidence for oligo-genetic inheritance.

Genes determining the bovine erythrocyte antigens were mapped by linkage analysis. In total 9591 genotypes of 20 grandsire families with 1074 sires from a grand-daughter design were elucidated for the genes determining the erythrocyte antigens EAA, EAB, EAC, EAF, EAJ, EAL, EAM, EAN', EAR', EAS, EAT', and EAZ according to standard paternity testing procedures in the blood typing laboratories. Linkage analyses were performed with 248 microsatellite markers, eight SSCP markers and four polymorphic proteins and enzymes covering the 29 autosomes and the pseudoautosomal region of the sex chromosomes. The number of informative meioses for the blood group systems ranged from 76 to 947. Blood group systems EAM and EAT' were non-informative. Most of the erythrocyte antigen loci showed significant linkage to a single chromosome and were mapped unequivocally. The genes determining erythrocyte antigen EAA, EAB, EAC, EAL, and EAS were mapped to chromosomes 15, 12, 18, 3, and 21, respectively. Lod-score values ranged from 11.43 to 107.83. Moreover, the EAF system could be mapped to chromosome 17. However, the EAN' system previously known as part of the EAF system could be mapped to chromosome 5. In addition, the blood group systems EAJ, the new EAN', EAR', and EAZ, showed significant linkage to microsatellite markers on various chromosomes and also to other blood groups. The appearance of a single blood group system might be therefore either dependent on the existence of other blood group systems or because of an interaction between different loci on various chromosomes as is known in humans and in pigs.

Animals↗
PubMed2002

Consensus and comprehensive linkage maps of bovine chromosome 24.

This study describes development of a consensus genetic linkage map of bovine chromosome 24 (BTA24). Eight participating laboratories contributed data for 58 unique markers including a total of 25 409 meioses. Eighteen markers, which were typed in more than one reference population, were used as potential anchors to generate a consensus framework map. The framework map contained 16 loci ordered with odds greater than 1000:1 and spanned 79.3 cM. Remaining markers were included in a comprehensive map relative to these anchors. The resulting BTA24 comprehensive map was 98.3 cM in length. Average marker intervals were 6.1 and 2.5 cM for framework and comprehensive maps, respectively. Marker order was generally consistent with previously reported BTA24 linkage maps. Only one discrepancy was found when comparing the comprehensive map with the published USDA-MARC linkage map. Integration of genetic information from different maps provides a high-resolution BTA24 linkage map.

Animals↗
PubMed2001

[Pharmacological treatment of children and adolescents with OCD].

This review describes the pharmacological treatment of obsessive-compulsive disorder (OCD) in children and adolescents. Several randomised, placebo-controlled trials have shown the efficacy of SSRI drugs in the treatment of this often disabling condition. Treatment with SSRI drugs for OCD in children and adolescents can be considered safe, according to published experiences. Side effects are similar to those described in adults and about 10% of children and adolescents treated have had to stop the treatment, owing to side effects. The use of medical treatment achieves a reduction in rather than a total remission of obsessive-compulsive symptoms. Therefore, medical treatment should always be combined with other strategies, of which the cognitive behavioural therapy (CBT) is best documented. The need for further research is stressed, especially studies combining different treatment strategies, and the efficacy of treatment in the long term.

Adolescent↗
PubMed2001

[Recurrence and survival after conventional low anterior resection for rectal cancer].

INTRODUCTION: The aim of the study was to evaluate the incidence of recurrence of local cancer, distant metastases and survival after conventional low anterior resection for cure in patients with rectal carcinoma, on the basis of the poor prognosis after colorectal cancer in Denmark. MATERIAL AND METHODS: Consecutive patients operated on in the nine Danish departments of surgical gastroenterology in 1992-1993. Retrospective collection of data on recurrence of local cancer, distant metastases, and over-all survival at the end of 1996. RESULTS: Of 268 patients, 77 (29%) developed recurrent local cancer and/or distant metastases. Forty-eight (18%) had local recurrence with a cumulative 5-year rate of 39%. Distant metastases were seen in 54 (20%). The local recurrence rate increased with increasing Dukes' tumour stage and was higher after operation by a non-specialist (30%) than by a consultant, another specialist, or a surgeon under training and supervised by a consultant (15-17%) (p = 0.04). Multiple regression showed that the recurrence rate was independent of tumour localisation, blood loss, transfusion, anastomotic leakage, and status of the surgeon. The cumulative crude 5-year survival was 50% and independent of the status of the surgeon. DISCUSSION: Our relatively high local recurrence rate and the results in the literature after total mesorectal excision (TME) indicate that the conventional technique should be replaced by TME, which has become the recommended method in recent years. Furthermore, we propose a changed strategy in the treatment of rectal cancer. The patients should be treated in fewer departments with established teams of rectal cancer specialists taking part in all operations for rectal cancer.

Adenocarcinoma↗
PubMed2001

A whole genome scan for differences in recombination rates among three Bos taurus breeds.

Twenty paternal half-sib families of a granddaughter design were genotyped for 265 genetic markers, most of them microsatellites. These were 16 Holstein families, 3 Simmental families, and 1 Brown Swiss family. The number of sires per breed was 872, 170, and 32, respectively. Two-point recombination rates were estimated both jointly for all breeds and each single breed separately. Of 1168 marker intervals, 865 provided estimates for at least two breeds. Differences between breeds were tested by likelihood ratio tests. Four marker intervals, representing three genomic regions on BTA19, BTA24, and BTA27, show a significant impact of the breed at a false discovery rate of 0.23 and indicate a genetic component of observed heterogeneity of recombination. The variability of recombination rates between cattle breeds might not be a common feature of the whole genome, but rather might be restricted to certain chromosomal segments. Thus, attention should be paid to heterogeneities when pooling data of such regions from different breeds.

Animals↗
PubMed2001

A mammary gland EST showing linkage disequilibrium to a milk production QTL on bovine Chromosome 14.

As part of a genome scan, ESTs derived from mammary gland tissue of a lactating cow were used as candidate genes for quantitative trait loci (QTL), affecting milk production traits. Resource families were genotyped with 247 microsatellite markers and 4 polymorphic ESTs. It was shown by linkage analysis that one of these ESTs, KIEL_E8, mapped to the centromeric region of bovine Chromosome (Chr) 14. Regression analysis revealed the presence of a QTL, with significant effect on milk production, in this chromosome region, and analysis of variance showed no significant interaction of marker genotype and family. The estimated significant differences between homozygous marker genotypes were 140 kg milk, -5.02 kg fat yield, and 2.58 kg protein yield for the first 100 days of lactation. Thus, there was strong evidence for a complete or nearly complete linkage disequilibrium between KIEL_E8 and the QTL. To identify the biological function of KIEL_E8, we extended the sequence for 869 bp by 5'-RACE. A 560-bp fragment of this shows a 90.9% similarity to a gene encoding a cysteine- and histidine-rich cytoplasmic protein in mouse. Although such a protein may have a regulatory function for lactation and a linkage disequilibrium between the EST marker and the QTL has been observed, it remains to be elucidated whether they are identical or not. Nevertheless, KIEL_E8 will be an efficient marker to perform marker-assisted selection in the Holstein-Friesian population.

Alleles↗
PubMed2001

Comprehensive linkage map of bovine chromosome 27.

The results of genotypic data contributed to the International Society for Animal Genetics (ISAG) Bovine Chromosome 27 Workshop are presented. Eight laboratories contributed 23 261 informative meioses from 44 loci. Eighteen loci were typed by at least two laboratories and were used to construct a consensus linkage map. Twenty-one loci were subsequently incorporated into a comprehensive map. The sex-averaged consensus map covered 66.9 cM. The sex-averaged comprehensive map was 75.5 cM, while the female and male maps were 73.1 and 63.7 cM, respectively. Five loci were excluded from the analysis because of ambiguous position in the linkage group and a low LOD score (less than 2.0). Average distance between loci in the comprehensive map was 1.98 cM.

Animals↗
PubMed2001

Comprehensive linkage map of bovine chromosome 11.

The results of genotypic data contributed to the International Society of Animal Genetics (ISAG) Bovine Chromosome 11 (BTA11) Workshop are presented. Six laboratories contributed a total of 26 199 informative meioses from 80 loci. Thirty-six loci were typed by at least two independent laboratories and were used to construct a consensus linkage map of the chromosome. The remaining loci were subsequently incorporated into a comprehensive map. The sex-averaged consensus map covered 128.9 cM. The female consensus map was 101.2 cM, while the male consensus map was 129.8 cM. The comprehensive sex-averaged map was 134.2 cM and the average genetic distance between loci was 1.72 cM.

Animals↗