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Biomedical subjects

D Grace

Publications and source records attributed to D Grace.

26 records · Page 2Linked to original sources
PubMed1981

The entire compound autosomes of Drosophila melanogaster.

Three new unusual compound chromosomes have been synthesized in Drosophila melanogaster. They consist of two homologous autosomes joined together in the new order: right arm, left arm, centromere, left arm, right arm, for each of the two major autosomes, and one in which chromosomes 2 and 3 have been combined in the order: right arm of 2, left arm of 2, centromere, left arm of 3, right arm of 3. The attachments of the autosomal arms were accomplished by obtaining chromosome breaks at or very close to the ends of the left arms of the autosomes such that no essential chromosome material has been removed; the compounds derived from them are therefore referred to as entire compounds. These large chromosomes are recovered in progeny with frequencies lower than expectation partly because of zygote mortality associated with these chromosomes, and partly because of a failure of spermiogenesis.

Animals↗
PubMed1981

Terminal chromosome attachments.

Descriptions are presented of four cases of attachment of chromosome material at the ends of normal chromosomes in Drosophila. Since no material appears to be missing from the polytene chromosomes and there are no ill effects to the organism in morphology, viability, or fertility when the chromosome is made homozygous, it is argued that the attachment occurred without the loss of any essential genetic material and that, in all probability, the break at the end of the chromosome occurred within the telomere of the chromosome. These cases may serve as a parallel to cases of apparent terminal breakage and reunion in certain rearrangements in man.

Animals↗
PubMed1980

Genetic analysis of the dumpy complex locus in Drosophila melanogaster: complementation, fine structure and function.

An extensive genetic analysis of the dumpy locus is presented. This study includes complementation, fine structure mapping and allelic interaction. A number of complementing recessive lethals of the dp complex have been genetically mapped. Two alleles of the ol(v) type that complement l alleles map to the left portion of the locus. A number of olv alleles that complement both l and lv lethals map within the right portion of the locus.--Fine-structure analysis demonstrated that both olv and o alleles are distributed among various subloci. Evidence for spacer regions between subloci is presented.--An extensive discussion of the data considers whether the locus is unicistronic or multicistronic. The conclusion reached is that the locus is not a single functional cistron. The possibility of a single cistron encoding a multifunctional polypeptide is discussed.--The hypothesis is proposed that the left portion of the map and the l mutations function as regulatory sequences and that the right portion of the map encodes structural sequences.

Alleles↗
PubMedDate not supplied

Radiographic evaluation of bone grafts.

Autogenous and allogenic bone grafts are frequently used in foot and ankle surgery. Indications may include treatment of nonunions, acute fractures, arthrodesis procedures, and reconstructive osteotomies. Proper perioperative management of these procedures requires a through understanding of the radiographic changes that occur after bone grafting. This article describes normal and abnormal radiographic presentations in both the recipient and donor sites after bone graft surgery.

Bone Transplantation↗
PubMedDate not supplied

Modified lapidus arthrodesis for adolescent hallux abducto valgus.

The Lapidus arthrodesis was originally described for the surgical correction of hallux valgus associated with metatasus primus adductus. It was popularized on the adult patient with moderate to severe hallux valgus deformity. However, the authors present a retrospective review of 23 adolescents between the ages of 13 and 20 who underwent the procedures. Characteristics of adolescent hallux valgus include a smaller dorsal medial eminence, less valgus rotation of the hallux, and certain mechanical influences. These influences may include a generalized increase in motion at the first metatarsocuneiform joint. The modified Lapidus arthrodesis eliminates motion at the first metatarsocuneiform joint and therefore directly addresses an etiology of the deformity. Both preoperative and postoperative radiographs were evaluated for reduction in the 1-2 intermetatarsal angle. Patients were evaluated through either chart review or telephone interview for present activity level, comfortable footgear, and overall satisfaction of the procedure. Twenty-seven out of 30 feet (90%) had either a good or excellent result with only three complications and two recurrences over a mean follow-up of 61 months.

Adolescent↗