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R Hope

Publications and source records attributed to R Hope.

At least 19 recordsLinked to original sources
PubMed2001

An orphaned mammalian beta-globin gene of ancient evolutionary origin.

Mammals possess multiple, closely linked beta-globin genes that differ in the timing of their expression during development. These genes have been thought to be derived from a single ancestral gene, by duplication events that occurred after the separation of the mammals and birds. We report the isolation and characterization of an atypical beta-like globin gene (omega-globin) in marsupials that appears to be more closely related to avian beta-globin genes than to other mammalian beta-globin genes, including those previously identified in marsupials. Phylogenetic analyses indicate that omega-globin evolved from an ancient gene duplication event that occurred before the divergence of mammals and birds. Furthermore, we show that omega-globin is unlinked to the previously characterized beta-globin gene cluster of marsupials, making this the first report of an orphaned beta-like globin gene expressed in a vertebrate.

Amino Acid Sequence↗
PubMed1999

Evolution and molecular characterization of a beta-globin gene from the Australian Echidna Tachyglossus aculeatus (Monotremata).

Coinciding with a period in evolution when monotremes, marsupials, and eutherians diverged from a common ancestor, a proto-beta-globin gene duplicated, producing the progenitors of mammalian embryonic and adult beta-like globin genes. To determine whether monotremes contain orthologues of these genes and to further investigate the evolutionary relationships of monotremes, marsupials, and eutherians, we have determined the complete DNA sequence of an echidna (Tachyglossus aculeatus) beta-like globin gene. Conceptual translation of the gene and sequence comparisons with eutherian and marsupial beta-like globin genes and echidna adult beta-globin indicate that the gene is adult expressed. Phylogenetic analyses do not clearly resolve the branching pattern of mammalian beta-like globin gene lineages and it is therefore uncertain whether monotremes have orthologues of the embryonic beta-like globin genes of marsupials and eutherians. Four models are proposed that provide a framework for interpreting further studies on the evolution of beta-like globin genes in the context of the evolution of monotremes, marsupials, and eutherians.

Amino Acid Sequence↗
PubMed1998

Community services. The home team.

Reorganising a mental health service for elderly people to ensure most care can be given in the client's home has led to a dramatic decrease in admissions. Length of inpatient stay has not fallen, probably because those now admitted are more severely ill. The service is based on community mental health teams and places great reliance on healthcare assistants.

Aged↗
PubMed1993

Genetic variation within and between strains of outbred Swiss mice.

The aim of this survey was to measure levels of genetic variation within and between 5 different strains of outbred Swiss mice. Ten to 15 animals from each strain (NIH, Q(S), ARC, IMVS and STUD) were typed, using allozyme electrophoresis, at 10 gene loci: Mod-1, Idh-1, Gpi-I, Es-1, Es-3, Hbb, Pep-3, Gr-1, Got-2 and Pgm-1. Polymorphic variation in at least one of the 5 strains was detected at all 10 loci. The proportion of polymorphic loci ranged from 0.3 (NIH) to 0.8 (IMVS) with a mean of 0.52. Average expected heterozygosities ranged from 0.08 (NIH) to 0.37 (IMVS) with a mean of 0.21. The inbred strain SWR was, as expected, homozygous at all 10 loci. The amount of allelic substitution between pairs of strains was quantified using Nei's genetic distance, and a dendrogram based on these genetic distances showed a close overall similarity in its branching pattern to the known genealogy of the strains. This survey showed that a considerable degree of genetic variation persists in the 5 strains examined, a level of variation similar to that previously detected by Rice and O'Brien (1980) in 3 other outbred Swiss strains.

Animals↗
PubMed1992

Restriction fragment length variants in the marsupial Sminthopsis crassicaudata.

A fully pedigreed colony of the dasyurid marsupial Sminthopsis crassicaudata has provided material for establishing two panels of DNA samples: a broadbased test panel and a two-generation family panel. These have been used to search for genetic markers in the form of restriction fragment length variants. The molecular probes--pSG-2H, a region of the S. crassicaudata embryonic beta-globin gene; pB8.BS, a region of the human ubiquitin gene, and p3-21a1:1, a region of the processed pseudogene of phosphoglycerate kinase-1 of the macropodid marsupial Macropus robustus--were hybridized to Southern blots of EcoR1-digested DNA from the panels. Analysis of these blots when probed with pSG-2H provided evidence of two alleles segregating at a single EcoR1 site. Analysis of the same blots when probed with pB8.BS suggested allelic variation at two closely linked EcoR1 sites. Probing the blots with p3-21a1:1 produced a complex pattern of bands resembling DNA fingerprints. The presence of a 12.3-kb band was found to conform to a simple autosomal dominant mode of inheritance. Analysis of the family data, for each probe, revealed no significant departure from Mendelian inheritance. This work has provided additional genetic markers that will enhance the use of S. crassicaudata as a model marsupial species and has demonstrated that a high level of genetic variability has been maintained in the marsupial colony.

Animals↗
PubMed1988

Scalping injuries: new technique for stabilization of flaps to the skull.

Extensive scalping injuries offer a unique challenge for tissue coverage because of the wide expanse of bone and lack of deep soft tissue or significant perforating vessels. For smaller injuries, pedicle flaps offer ideal coverage. Larger defects can be covered by omental flaps. Coverage with a free muscle flap followed by split-thickness skin grafting offers optimal long-term coverage. Two new techniques are introduced. The wire-button technique offers stabilization, and the halo frame provides good support and protection for a new free-flap graft and may increase the success rate of flaps in patients with scalping injuries.

Humans↗
PubMed1987

Localization of MIC5 to the region between HPRT and G6PD on the human X chromosome.

The X-linked gene, MIC5, encodes a human cell-surface antigen, R1. We have assigned MIC5 to the region between HPRT and G6PD on the long arm of the X chromosome. Regional localization was based on the pattern of reactivity of the R1 monoclonal antibody with human-rodent somatic cell hybrids which contained different fragments of the human X chromosome.

Antibodies, Monoclonal↗
PubMed1985

Cloning and chromosomal location of the alpha- and beta-globin genes from a marsupial.

The cDNA sequences encoding the adult alpha- and beta-globin polypeptides of a marsupial, the native cat Dasyurus viverrinus, have been cloned and their nucleotide sequences have been determined. Using these cDNA clones we have determined the chromosomal location of the native cat alpha- and beta-globin genes by in situ hybridization to fixed metaphase chromosomes and by hybridization to DNA extracted from chromosomes purified by a fluorescence-activated cell sorter. Using two independent methods of gene assignment we have shown the alpha- and beta-globin-like gene sequences to be asyntenic in the native cat, the alpha-globin-like sequences being on chromosome 2 and the beta-globin-like sequences being on chromosome 4.

Animals↗