Variation in dinucleotide (GT) repeat sequence in the first exon of the STAT6 gene is associated with atopic asthma and differentially regulates the promoter activity in vitro.
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Biomedical subjects
Publications and source records attributed to M Moller.
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Black spotting on a red or white background in pigs is determined by the E(P) allele at the MC1R/Extension locus. A previous comparison of partial MC1R sequences revealed that E(P) shares a missense mutation (D121N) with the E(D2) allele for dominant black color. Sequence analysis of the entire coding region now reveals a second mutation in the form of a 2-bp insertion at codon 23 (nt67insCC). This mutation expands a tract of six C nucleotides to eight and introduces a premature stop codon at position 56. This frameshift mutation is expected to cause a recessive red color, which was in fact observed in some breeds with the E(P) allele present (Tamworth and Hereford). RT-PCR analyses were conducted using skin samples taken from both spotted and background areas of spotted pigs. The background red area had transcript only from the mutant nt67insCC MC1R allele, whereas the black spot also contained a transcript without the 2-bp insertion. This indicates that black spots are due to somatic reversion events that restore the frame and MC1R function. The phenotypic expression of the E(P) allele is highly variable and the associated coat color ranges from red, red with black spots, white with black spots, to almost completely solid black. In several breeds of pigs the phenotypic manifestation of this allele has been modified by selection for or against black spots.
The synthesis of liquid crystalline 3,4,5-tris(11-methacryloylundecyl-1-oxybenzyloxy)benzoic acid, 2-methyl-(1,4,7,10,13-pentaoxacyclopentadecane)-3,4,5-tris[4-(11-methacryloylundecyl-1-oxy)benzyloxy] benzoate and its 1:1 complex with sodium triflate is described. The observed mesophases were identified, by polarized optical microscopy and contact preparation techniques, to be of hexagonal columnar disordered structure. The amphiphiles form lyotropic columnar phases in concentrated methacrylate solvents, while at low solute contents supramolecular organogels emerge.
Mammary spindle-cell tumours and sarcomas seem to be restricted to dogs and humans. Two cell lines from spontaneous primary canine mammary spindle-cell tumours (CMT-U304 and CMT-U309) and two cell lines from spontaneous primary canine mammary osteosarcomas (CMT-U334 and CMT-U335) were established to study the mesenchymal phenotypes of mammary tumours in the female dog. The cells from the spindle-cell tumours expressed cytokeratin, vimentin and smooth muscle actin filaments. When these cells were inoculated subcutaneously into female and male nude mice they formed different types of mesenchymal tumours such as spindle-cell tumours, fibroma and rhabdomyoid tumours (n = 6/8). The cells from the osteosarcomas expressed vimentin filaments and also formed different types of mesenchymal tumours such as chondroid, rhabdomyoid, smooth muscle-like and spindle-cell tumours (n = 6/10). The cell lines CMT-U304, CMT-U309 and CMT-U335 had receptors for progesterone but none of the four cell lines had receptors for estrogen. All four cell lines and their corresponding primary tumours showed identical allelic patterns in microsatellite analysis. By in situ hybridization with genomic DNA we could verify that all formed tumours but one were of canine origin. Our results support the hypothesis that canine mammary tumours are derived from pluripotent stem cells.
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The purpose of this study was to localize pathological magnetic brain activities and to analyze metabolic alterations in functionally abnormal lesions by using magnetoencephalography (MEG) and (1)H magnetic resonance (MR) spectroscopy in patients with brain tumors. The authors studied 10 healthy volunteers and seven patients who harbored common brain tumors, namely astrocytic tumors and meningioma. In spontaneous MEG the pathological brain activities (slow waves, fast waves, and spikes) were localized using a single equivalent dipole model. After the results of MEG and (1)H MR spectroscopy were superimposed onto the corresponding MR images, the signal intensities of spectroscopically visible metabolites were analyzed in the regions in which the dipoles of the pathological activities were concentrated. Increased slow-wave activity was observed in four cases, and fast-wave or spike activity was significantly increased in one case each, respectively. These pathological activities were localized at almost the same cortical areas adjacent to the bulk of tumors, where mild reduction of N-acetyl aspartate (NAA) and slight accumulation of lactate consistently existed. Preserved and metabolically active cortical areas, which are indicated by residual NAA, might be able to generate pathological magnetic activities under lactic acidosis. Such an area could be understood as a border zone between normal brain tissue and brain tissue that has been seriously damaged by tumors or associated edema, which should be intensively treated. This combination of imaging techniques gives insight into functional as well as metabolic aspects of pathological brain conditions.
The authors conducted a study to evaluate the clinical outcome in 50 patients with lesions around the motor cortex who underwent surgery in which functional neuronavigation was performed. The sensorimotor cortex was identified in all patients with the use of magnetoencephalography (MEG). The MEG-source localizations were superimposed onto a three-dimensional magnetic resonance image, and the image data set was then implemented into a neuronavigation system. Based on this setup, the surgeon chose the best surgical strategy. During surgery, the pre- and postcentral gyrus were identified by neuronavigation, and in addition, the central sulcus was localized using intraoperative recording of somatosensory evoked potentials. In all cases MEG localizations of the sensory or motor cortex were correct. In 30% of the patients preoperative paresis improved, in 66% no additional deficits occurred, and in only 4% (two patients) deterioration of neurological function occurred. In one of these patients the deterioration was not related to the method. The method of incorporating functional data into neuronavigation systems is a promising tool that can be used in more radical surgery to cause less morbidity around eloquent brain areas.
The roan coat color in horses is controlled by a dominant allele that is lethal in the homozygous condition. Phenotypic similarities to some pigmentation disorders in human and mouse, combined with comparative mapping data, identified KIT, encoding the mast cell growth factor receptor, as a major candidate gene for the roan locus (Rn). Rn has previously been mapped to equine linkage group (LG) II. In this study, LGII was expanded with KIT and PDGFRA (platelet-derived growth factor receptor alpha) by use of RFLP and linkage analysis. Moreover, highly significant linkage disequilibrium between Rn and a KIT TaqI RFLP, representing a synonymous substitution in exon 19, was revealed. There was a strong KIT-Rn association in most breeds. Almost the complete KIT-encoding sequence was determined by sequence analysis of RT-PCR products. Comparison of horse KIT cDNA sequences, representing three different alleles (two different rn and one Rn), revealed five sequence polymorphisms and several mRNA splice variants, but none of these proved to be specifically associated with Rn. An insertion of a partial (79 bp) LINE1-element between exons 1 and 2, leading to a frameshift, represented about 30% of KIT transcripts in the Belgian roan horse used for the sequence analysis. However, an association between this L1 splice insertion and the roan phenotype was not verified when testing additional unrelated roan and non-roan horses from different breeds. The study strengthens the hypothesis that the roan coat color is controlled by KIT, but further analyses are needed to reveal the causative mutation(s).
Arginine vasopressin (AVP) is the main antidiuretic hormone in mammals and arginine vasotocin (AVT) in submammalian vertebrates. The possibility that the genetic material encoding AVT is maintained in mammals is controversial. In this study, we investigated by radioactive in situ hybridization the possible presence of the mRNA encoding AVP and AVT, and using immunocytochemistry the presence of structures immunoreactive for AVP and AVT in the bovine pineal gland. In situ hybridization was performed by use of 35S-labelled oligoprobes. Immunocytochemistry was performed using specific polyclonal rabbit antibodies and the avidin-biotin-complex method. In situ hybridization revealed positive signals for both AVP mRNA and AVT mRNA in a few cells scattered throughout the pineal body. Immunocytochemistry revealed thin AVP-immunoreactive fibres in the pineal stalk and the pineal gland. It also revealed staining of several AVT-immunoreactive nerve fibres in both the pineal stalk and the gland. In addition, polyhedral, neuron-like cell bodies from which two to three processes emerged were also AVT-immunoreactive. Thus, our investigation shows the presence of AVP/AVT-immunoreactive cellular structures in the bovine pineal gland. Our data further show the presence of mRNAs encoding both AVT and AVP. We therefore suggest that AVT mRNA is translated into an AVT-like peptide in the bovine pineal.
OBJECTIVE: In this study, the intraoperative visualization of functional data provided by functional magnetic resonance imaging (fMRI) and magnetoencephalography (MEG) leading to functional neuronavigation is demonstrated in surgery around the motor strip. METHODS: In seven patients with lesions adjacent to the central region, fMRI was performed with a 1.5-Tesla magnetic resonance system, using axial echo-planar imaging with a motor and a sensory task. Somatosensory and motor evoked fields were recorded with a biomagnetometer. fMRI and MEG were matched to an anatomic three-dimensional magnetic resonance image set by a contour fit. Then this three-dimensional image data set was transferred to the navigation microscope and displayed in the eyepieces of the microscope during surgery. Additionally, intraoperative recording of somatosensory evoked potentials was performed for verification of the central sulcus. RESULTS: In all cases, the projection of fMRI and MEG data into the operating viewing field allowed easy identification of the central region, which was confirmed by phase reversal of somatosensory evoked potentials in each case. fMRI and MEG measurements yielded corresponding results in each patient. CONCLUSION: Functional neuronavigation with integration of fMRI and MEG allows the fast identification of eloquent brain areas. The widespread availability of fMRI will result in a broad availability of functional neuronavigation, which will, in turn, contribute to the successful surgery of lesions in eloquent brain areas with lower morbidity.
The intergeniculate leaflet (IGL) is a distinct division of the lateral geniculate complex that participates in the regulation of the circadian rhythm through its projections to the circadian pacemaker located in the suprachiasmatic nuclei of the hypothalamus. A high number of neuropeptide Y (NPY) cell bodies has been described in the IGL by immunohistochemistry and in situ hybridization. The present study investigated whether NPY in the IGL is influenced by the length of the daily photoperiod. By using in situ hybridization we show a significant increase of the number of NPY mRNA containing neurons in the mid-part of the IGL of Syrian hamsters maintained in a short photoperiod compared to those kept in a long photoperiod. On the other hand, NPY mRNA expression per cell in the IGL is similar in both photoperiods tested.
Immune capacity traits show considerable genetic variation in outbred populations. To identify quantitative trait loci (QTLs) for immune capacity in the pig, various measures of immune function (total and differential leukocyte counts, neutrophil phagocytosis, mitogen-induced proliferation, IL-2 production, and virus induced IFN-alpha production in whole blood cultures, and Ab responses to two Escherichia coli antigens) were determined in 200 F2 animals from a wild pig-Swedish Yorkshire intercross. The pedigree has been typed for 236 genetic markers covering all autosomes, the X chromosome and the X/Y pseudoautosomal region. Through interval mapping using a least-squares method, four QTLs with significant effects were identified; one for total leukocyte counts, one for mitogen-induced proliferation, one for prevaccination levels of Abs to E. coli Ag K88, and one for Ab response to the O149 Ag. In addition, several putative QTLs were indicated. The results from the present study conclusively show that it is possible to identify QTLs for immune capacity traits in outbred pig populations by genome analysis.
Somatostatin is known to mediate its actions through five G-protein-coupled receptors (sst1-sst5). We have studied the expression of the sst1 receptor in the rat hypothalamus by using a subtype-specific antiserum. In Western blotting, the antiserum reacted specifically with a band with an apparent molecular weight of 80,000 in membranes prepared from hypothalamic tissue. The localization of the sst1 receptor was investigated by immunohistochemistry in hypothalamus sections. Additionally, an immunofluorescent double-labeling was performed for the sst1 receptor and somatostatin. Light microscopy revealed that the sst1 receptor is located in perikarya and nerve fibers in the rostral periventricular area surrounding the third ventricle as well as in nerve fibers projecting from the perikarya to the external layer of the median eminence. In these neuronal structures, sst1 immunoreactivity was found to be colocalized with somatostatin. Furthermore, the location of sst1 receptors was studied by immunoelectron microscopy in the median eminence. In the external layer, receptor immunoreactivity was confined to nerve terminals. Immunoreactive nerve terminals were seen to make synapse-like junctions with other both stained and unstained nerve terminals. Thus, the sst1 receptor is present in the classic somatostatinergic hypothalamic parvocellular system inhibiting hormone secretion from the anterior pituitary gland. These findings indicate that the sst1 receptor may act as an autoreceptor and inhibit the release of somatostatin from periventricular neurons projecting to the median eminence.
A prominent innervation of the pineal gland of the European hamster with nerve fibres containing neuropeptide Y (NPY) and tyrosine hydroxylase (TH) was demonstrated by means of immunohistochemistry. Nearly all the TH- and NPY-immunoreactive nerve fibres in the superficial pineal gland disappeared after bilateral superior cervical ganglionectomy, showing that the majority of NPY- and TH-immunoreactive nerve fibres belonged to the sympathetic nervous system. Since, in the European hamster, preliminary studies of the NPY-fibre density in the pineal gland had indicated seasonal changes, the density of NPY-immunoreactive nerve fibre profiles was ascertained in the superficial pineal gland in a series of animals between the first part of November and late April. The highest density of NPY-immunoreactive nerve fibre profiles was observed during midwinter. On the other hand, during the same period of the year, the number of sympathetic TH-immunoreactive sympathetic nerve fibre profiles did not exhibit seasonal variation, nor did substitution of testosterone, during the sexually inactive period, affect the density of NPY-containing nerve fibres in the gland. Our results show the presence of a testosterone-independent annual variation in the content of NPY in the sympathetic nerve fibres innervating the pineal gland of the European hamster. This variation can be correlated with the changes in the daily pattern of melatonin production observed by others in the same species at this period of the year.
A quantitative trait locus (QTL) analysis of growth and fatness data from a three generation pig experiment is presented. The population of 199 F2 animals was derived from a cross between wild boar and Large White pigs. Animals were typed for 240 markers spanning 23 Morgans of 18 autosomes and the X chromosome. A series of analyses are presented within a least squares framework. First, these identify chromosomes containing loci controlling trait variation and subsequently attempt to map QTLs to locations within chromosomes. This population gives evidence for a large QTL affecting back fat and another for abdominal fat segregating on chromosome 4. The best locations for these QTLs are within 4 cM of each other and, hence, this is likely to be a single QTL affecting both traits. The allele inherited from the wild boar causes an increase in fat deposition. A QTL for intestinal length was also located in the same region on chromosome 4 and could be the same QTL with pleiotropic effects. Significant effects, owing to multiple QTLs, for intestinal length were identified on chromosomes 3 and 5. A single QTL affecting growth rate to 30 kg was located on chromosome 13 such that the Large White allele increased early growth rate, another QTL on chromosome 10 affected growth rate from 30 to 70 kg and another on chromosome 4 affected growth rate to 70 kg.
The melanocortin receptor 1 (MC1R) plays a central role in regulation of eumelanin (black/brown) and phaeomelanin (red/yellow) synthesis within the mammalian melanocyte and is encoded by the classical Extension (E) coat color locus. Sequence analysis of MC1R from seven porcine breeds revealed a total of four allelic variants corresponding to five different E alleles. The European wild boar possessed a unique MC1R allele that we believe is required for the expression of a wild-type coat color. Two different MC1R alleles were associated with the dominant black color in pigs. MC1R*2 was found in European Large Black and Chinese Meishan pigs and exhibited two missense mutations compared with the wild-type sequence. Comparative data strongly suggest that one of these, L99P, may form a constitutively active receptor. MC1R*3 was associated with the black color in the Hampshire breed and involved a single missense mutation D121N. This same MC1R variant was also associated with EP, which results in black spots on a white or red background. Two different missense mutations were identified in recessive red (e/e) animals. One of these, A240T, occurs at a highly conserved position, making it a strong candidate for disruption of receptor function.
The change of phenotypic traits in domestic animals and crops as a response to selective breeding mimics the much slower evolutionary change in natural populations. Here, we describe that the dominant white phenotype in domestic pigs is caused by two mutations in the KIT gene encoding the mast/stem cell growth factor receptor (MGF), one gene duplication associated with a partially dominant phenotype and a splice mutation in one of the copies leading to the fully dominant allele. The splice mutation is a G to A substitution in the first nucleotide of intron 17 and leads to skipping of exon 17. The duplication is most likely a regulatory mutation affecting KIT expression, whereas the splice mutation is expected to cause a receptor with impaired or absent tyrosine kinase activity. Immunocytochemistry showed that this variant form is expressed in 17- to 19-day-old pig embryos. Hundreds of millions of white pigs around the world are assumed to be heterozygous or homozygous for the two mutations. [The EMBL accession numbers for porcine KIT1*0101, KIT1*0202, KIT2*0202, and KIT2*0101 are AJ223228-AJ223231, respectively.]
An intercross between wild boar and a domestic Large White pig population was used to map quantitative trait loci (QTL) for body proportions, weight of internal organs, carcass composition, and meat quality. The results concerning growth traits and fat deposition traits have been reported elsewhere. In the present study, all 200 F2 animals, their parents, and their grandparents were genotyped for 236 markers. The marker genotypes were used to calculate the additive and dominance coefficients at fixed positions in the genome of each F2 animal, and the trait values were regressed onto these coefficients in intervals of 1 cM. In addition, the effect of proportion of wild boar alleles was tested for each chromosome. Significant QTL effects were found for percentage lean meat and percentage lean meat plus bone in various cuts, proportion of bone in relation to lean meat in ham, muscle area, and carcass length. The significant QTL were located on chromosomes 2, 3, 4, and 8. Each QTL explained 9 to 16% of the residual variance of the traits. Gene action for most QTL was largely additive. For meat quality traits, there were no QTL that reached the significance threshold. However, the average proportion of wild boar alleles across the genome had highly significant effects on reflectance and drip loss. The results show that there are several chromosome regions with a considerable effect on carcass traits in pigs.