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N J Larsen

Publications and source records attributed to N J Larsen.

At least 19 recordsLinked to original sources
PubMed2001

Human FATE is a novel X-linked gene expressed in fetal and adult testis.

Previously, we identified a partial cDNA sequence of a novel human transcript, designated fetal and adult testis expressed transcript (FATE). FATE is testis-specific in fetal life and co-expressed with SRY in a 7 weeks old fetal testis, suggesting a function in early testicular differentiation. Herein, full-length cDNA clones of human and porcine FATE were isolated and the gene structure and promoter region of the human FATE gene was characterized. The human FATE gene, which maps to Xq28, consists of five exons spanning approximately 7 kb of genomic DNA. Examination of 1 kb of the FATE promoter region revealed the presence of a putative steroidogenic factor 1 (SF-1) binding site at position -79 to -71 upstream of the transcription start site. We propose that FATE might represent a novel target gene of SF-1 in human testicular differentiation and/or germ cell development.

Adult↗
PubMed1999

A comparative linkage and physical map of bovine chromosome 24 with human chromosome 18.

Polymorphic microsatellites have been developed in the vicinity of nine genes on bovine chromosome (BTA) 24, all orthologous to genes on human chromosome (HSA) 18. The microsatellites have been isolated from bacterial and yeast artificial chromosome clones containing the genes. A linkage map was developed including these polymorphic markers and four anonymous, published microsatellites. Yeast artificial chromosomes containing six of these genes have also been mapped using fluorescent in situ hybridization (FISH), thereby tying the linkage map together with the physical map of BTA24. Comparing gene location on HSA18 and BTA24 identifies four regions of conserved gene order, each containing at least two genes. These genes identify six regions of conserved order between human and mouse, two more than in the human-bovine comparison. The breakpoints between regions of conserved order for human-bovine are also breakpoints in the human-mouse comparison. The centromere identifies a fifth conserved region if the BTA24 centromere is orthologous with the HSA18 centromere.

Animals↗
PubMed1999

New insights into porcine-human synteny conservation.

Eleven genes were mapped to the porcine genome with the aim of improving the human-porcine comparative gene map. Five of these genes were from regions of the human genome painted by porcine chromosomal probes; of these, two mapped to chromosomes not expected from the painting results. Among the six genes from human regions not painted by porcine chromosomal probes, three genes did not map where expected by the principle of parsimony. Several of the gene assignments indicate the existence of small regions of conserved synteny not detected by heterologous chromosome painting, especially in telomeric regions. We have also detected new rearrangements in gene order within the regions of correspondence between human Chromosome (HSA) 15 and porcine Chromosome (SSC) 1 as well as between HSA4 and SSC8.

Animals↗
PubMed1999

Mapping of two tumor suppressor genes in the pig.

Mutations in the breast cancer 1, early onset (BRCA1) gene confer an increased risk of breast and ovarian cancer in humans. The human MAD (mothers against decapentaplegic, Drosophila) homolog 4 (MADH4) locus is a target for deletion in pancreatic and other cancers. Given the role of the pig in biomedical studies, pig orthologs of BRCA1 and MADH4 were identified and localized in the porcine genome.

Animals↗
PubMed1998

Structure/function characterization of porcine CD59: expression, chromosomal mapping, complement-inhibition, and costimulatory activity.

BACKGROUND: Complement regulatory proteins have become important targets to potentially modulate inflammatory reactions or transplant rejection. Since pig into human xenotransplantation could potentially overcome the enormous shortage of donor organs and tissues, characterization of porcine complement regulatory proteins is critical. METHODS: The porcine CD59 cDNA has been isolated from porcine aortic endothelial cells and its structure determined. In addition, a molecular genetic analysis of the gene and its transcriptional properties and a functional analysis have been performed utilizing the transfected cDNA. RESULTS: The most prominent mRNA species is 1.8 kilobases but cloned reverse transcriptase polymerase chain reaction products suggest that multiple polyadenylation sites are utilized. Gene mapping was performed utilizing a polymorphism identified in the 3' UT, and the gene was localized to within 3 cM of follicle-stimulating hormone, beta polypeptide in the middle of the chromosome 2 linkage map. RNA expression was equivalent in endothelial, kidney, and testis cell lines. Comparisons have been made with CD59 sequences from other species to identify possible important domains of the protein. The cDNA has been utilized to express an epitope-tagged or wild-type protein either transiently on COS-7 cells or stably in Chinese hamster ovary cells. The porcine CD59 protein effectively inhibited the antibody-mediated lytic activity of both porcine and human complement. In contrast to human CD59, porcine CD59 is incapable of providing costimulation to human T cells. CONCLUSIONS: These data suggest that overexpression of porcine CD59 might be more effective than human CD59 in prolonging xenograft survival with transgenic pig organs because of reduced immunoreactivity.

Amino Acid Sequence↗
PubMed1998

[Providing patients with their diagnostic test results. A vignette study in general practice].

The communication of results of HIV tests and chest-X-rays because of persistent coughing are of particular interest because potential life-threatening disease may be disclosed. For HIV tests it is recommended that the result is communicated to the patient in the doctor's office face to face. In this questionnaire study based on two simulated case-stories with a 63 year-old man referred to chest-X-rays because of persistent coughing, and a 27 year-old man, who had been living in Africa for some time, now wanting a HIV test performed, we found that only half (53%) of the general practitioners (GP) did communicate HIV test results in the consultation office. X-ray test results were only communicated in the consultation office by 18% of the GPs. Communication of test results which might have serious implications to the patient should preferably not be done by telephone. Patients should be told of potentially serious results in person by their own physician.

Adult↗