Search PubMed⌕ Search

Biomedical subjects

P Barton

Publications and source records attributed to P Barton.

At least 91 records · Page 5Linked to original sources
PubMed1985

Genes for skeletal muscle myosin heavy chains are clustered and are not located on the same mouse chromosome as a cardiac myosin heavy chain gene.

Myosin heavy chain (MHC) genes are expressed as several distinct isoforms in a tissue- and stage-specific manner; three skeletal muscle MHC isoforms appear sequentially during development. We have isolated cDNA clones, identified by RNA blot hybridization and by nucleotide sequence determination as coding for portions of the embryonic (pMHC2.2), perinatal (pMHC16.2A), and alpha(V1) cardiac (pMHC141 and pMHC101) MHC isoforms. These four probes and the adult skeletal MHC probe (pMHC32) have been used on Southern blots of genomic DNA to detect restriction fragment length polymorphisms defining the alleles for these genes in mouse species Mus musculus and Mus spretus. In this way, we followed the segregation of skeletal and cardiac MHC genes in 42 offspring resulting from an interspecies backcross. We found that the embryonic, perinatal, and adult skeletal MHC genes are clustered on chromosome 11 near the locus nude, the skeletal and cardiac MHC genes do not cosegregate, and the alpha(V1) cardiac MHC gene is located on chromosome 14 close to Np-1. This result is in contrast to that for other contractile protein genes such as the alkali myosin light chain and the actin multigene families, which are dispersed in the genome.

Animals↗
PubMed1983

Computed tomography demonstration of distal femoral (trochlear) articular groove: a normal variant.

In computed tomography of the skeleton, as in other radiologic modalities, recognition of normal skeletal variants is essential for defining the extent and type of injury or neoplasm. Computed tomography findings, because of the unique use of cross-sectional anatomy, must be carefully studied to avoid labeling a normal variant as an abnormal entity. We describe here an observation of a normal variant--distal femoral, anterior articular (trochlear) groove--found in a patient with an osteochondral fracture and loose intra-articular bony fragment.

Adult↗
PubMed1982

Localization of human immunoglobulin kappa light chain variable region genes to the short arm of chromosome 2 by in situ hybridization.

The genes for human immunoglobulin kappa light chains have been localized in normal lymphocyte and fibroblast chromosomes by in situ hybridization of probes from cloned DNA fragments of the kappa variable region locus. The localization was achieved by counting grains (after autoradiography) over chromosomes in a number of karyotypes. The variable region gene probes hybridized in a cluster on a region of the chromosome 2 short arm close to the centromere (2cen leads to p12). This location was confirmed in lymphocytes from a balanced translocation carrier 46XXt (2; 16) (q13; q22). Our results show that human kappa light chain genes are located in the region of the break point observed in specific chromosomal translocations associated with Burkitt lymphoma.

Binding Sites, Antibody↗
PubMed1981

The chromosomal distribution of repetitive DNA sequences within the human beta globin gene cluster.

The chromosomal distribution and degree of repetitiveness of the sequences within the human beta globin gene cluster has been studied by in situ hybridisation. A genomic recombinant, H beta G1, which contains 15.9 thousand base pairs (kb) of DNA inserted into lambda charon 4A, was used as a template for the [3H] complementary RNA used for hybridisation. The inserted DNA contains sequences 4.7 kb to the 5' side of the delta gene and continues through the delta and beta genes to a site 2.8 kb to the 3' side of the beta gene. Two highly repetitive sequences, which are distributed evenly over all the chromosomes, have been identified within this DNA. Another somewhat less repetitive sequence has been identified between the beta and delta genes.

Base Sequence↗
PubMed1981

Chromosomal localization of a single copy gene by in situ hybridization--human beta globin genes on the short arm of chromosome 11.

1. The localization of the beta globin genes by in situ hybridization to fixed chromosomes is described. 2. The probe used was a [3H]cRNA copy of a genomic clone containing in total 4.4 kb of DNA and including the beta globin gene. 3. The evidence for the localization of the gene comes from three pieces of data. (a) Chromosome 11 is labelled to double the extent expected if the grains were randomly distributed, (b) the extra grains above background are clustered on the short arm of 11 close to the centromere, and (c) the absolute number of grains observed is very close to that predicted for a probe of that length by comparison with ribosomal genes. The localization is in agreement with that obtained by other methods. 4. This method could be extended to any gene for which a genomic clone containing at least 5 kb of single copy DNA is available.

Chromosome Mapping↗
PubMed1980

Activities by the schools to improve the distribution of dentists: an AADS report.

It appears that most dental schools have not yet become actively involved in efforts to solve maldistribution problems. However, there seems to be increasing interest in the potential benefits of extramural experience programs. Coordination of efforts by the schools, the state dental associations, and the state boards of dental examiners is very limited, but is clearly needed. Admissions committees seem to be trying to take into account the needs of rural areas and the inner city as well. Finally, the results of the survey point up the need for further study of these problems and of the value of particular approaches to them.

Dentists↗