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D T Burke

Publications and source records attributed to D T Burke.

At least 55 records · Page 3Linked to original sources
PubMed1991

The role of yeast artificial chromosome clones in generating genome maps.

The cloning of large DNAs as yeast artificial chromosomes (YACs) holds the promise of greatly expanding the scope of physical genomic mapping. Recent improvements in YAC clone libraries and their screening, as well as in the analysis of YAC-cloned DNA, are beginning to fulfill the potential of this system.

Animals↗
PubMed1989

Mapping the Drosophila genome with yeast artificial chromosomes.

The ability to clone large fragments of DNA in yeast artificial chromosomes (YAC's) has created the possibility of obtaining global physical maps of complex genomes. For this application to be feasible, most sequences in complex genomes must be able to be cloned in YAC's, and most clones must be genetically stable and colinear with the genomic sequences from which they originated (that is, not liable to undergo rearrangement). These requirements have been met with a YAC library containing DNA fragments from Drosophila melanogaster ranging in size up to several hundred kilobase pairs. Preliminary characterization of the Drosophila YAC library was carried out by in situ hybridization of random clones and analysis of clones containing known sequences. The results suggest that most euchromatic sequences can be cloned. The library also contains clones in which the inserted DNA is derived from the centromeric heterochromatin. The locations of 58 clones collectively representing about 8 percent of the euchromatic genome are presented.

Animals↗
PubMed1989

Isolation of single-copy human genes from a library of yeast artificial chromosome clones.

A recently developed cloning system based on the propagation of large DNA molecules as linear, artificial chromosomes in the yeast Saccharomyces cerevisiae provides a potential method of cloning the entire human genome in segments of several hundred kilobase pairs. Most application of this system will require the ability to recover specific sequences from libraries of yeast artificial chromosome clones and to propagate these sequences in yeast without alterations. Two single-copy genes have now been cloned from a library of yeast artificial chromosome clones that was prepared from total human DNA. Multiple, independent isolates were obtained of the genes encoding factor IX and plasminogen activator inhibitor type 2. The clones, which ranged in size from 60 to 650 kilobases, were stable on prolonged propagation in yeast and appear to contain faithful replicas of human DNA.

Chromosomes, Fungal↗
PubMed1989

Cloning human telomeric DNA fragments into Saccharomyces cerevisiae using a yeast-artificial-chromosome vector.

Telomeric fragments of human DNA ranging in size from 50 to 250 kilobases were cloned into Saccharomyces cerevisiae using a yeast-artificial-chromosome (YAC) vector. Six human-telomeric YAC (HTY) strains were selected by virtue of the specific hybridization of their DNA with the human telomeric terminal-repeat sequence (TTAGGG)n, and the telomeric localization of this sequence within each YAC was demonstrated by its sensitivity to nuclease BAL-31. In situ hybridization of DNA from three of these HTY strains with human metaphase chromosomes yielded discrete patterns of hybridization signals at the telomeres of a limited number of human chromosomes, different for each clone. DNA from selected cosmid subclones of one of the HTY strains was used to localize the origin of the cloned telomeric DNA by in situ hybridization to the tip of the long arm of chromosome 7.

Base Sequence↗
PubMed1987

Cloning of large segments of exogenous DNA into yeast by means of artificial chromosome vectors.

Fragments of exogenous DNA that range in size up to several hundred kilobase pairs have been cloned into yeast by ligating them to vector sequences that allow their propagation as linear artificial chromosomes. Individual clones of yeast and human DNA that have been analyzed by pulsed-field gel electrophoresis appear to represent faithful replicas of the source DNA. The efficiency with which clones can be generated is high enough to allow the construction of comprehensive libraries from the genomes of higher organisms. By offering a tenfold increase in the size of the DNA molecules that can be cloned into a microbial host, this system addresses a major gap in existing experimental methods for analyzing complex DNA sources.

Chromosomes↗
PubMed1986

Oligodeoxynucleotide-directed mutagenesis of Escherichia coli and yeast by simple cotransformation of the primer and template.

A method of oligodeoxynucleotide-directed mutagenesis is presented which requires no in vitro DNA synthesis. Cotransformation of the synthetic primer and single-stranded template into competent spheroplasts of Escherichia coli or Saccharomyces cerevisiae generates the directed mutation. The desired event is detected genetically or by hybridization screening using the mutagenic oligodeoxynucleotide as a probe. The targeted mutation arises at a frequency of approximately 0.1%. In one extensively studied case in E. coli, involving creation of a 99-bp deletion, this procedure produced many fewer untargeted mutation events than did conventional protocols.

Escherichia coli↗
PubMedDate not supplied

Effects of hydrotherapy on pressure ulcer healing.

Pressure ulcers are a prevalent and potentially serious medical problem encountered in both the medical and rehabilitation settings. Because the progress of rehabilitation is often interrupted by the presence of pressure ulcers, the efficient care of these wounds is of great interest to the rehabilitation team. Patients in two acute care facilities with Stage III or IV pressure ulcers were identified and consented to participate in the study contained herein. All wounds were mechanically debrided of necrotic tissue, and then the patients were randomly assigned to the conservative treatment group (A; n = 18) or the conservative treatment plus whirlpool group (B; n = 24). Conservative treatment included measures to maximize pressure relief and wound care with wet-to-wet dressings using normal saline. The dressings were changed twice daily and when they became soiled. Whirlpool was administered for 20 min per day in Group B patients. Only those patients whose ulcers were followed-up for 2 or more wk were included in the study. Ulcers were then measured by a physician who was blinded as to the treatment groups. Ulcer dimension changes over time were compared between groups. The results indicate that the conservative treatment plus whirlpool group improved at a significantly faster rate than did the conservative treatment only group (P < 0.05).

Debridement↗
PubMedDate not supplied

Subjective swelling: a new sign for carpal tunnel syndrome.

This single-blinded, randomized cohort study of 186 patients was conducted to determine whether the subjective complaint of swelling of the hand or wrist is associated with the diagnosis and/or prognosis of carpal tunnel syndrome. All patients were referred for splinting with a presenting clinical diagnosis of carpal tunnel syndrome from outpatient specialty clinics, including orthopedics, rheumatology, and neurology. Patients were assessed before splinting for the complaint of subjective swelling and underwent a clinical examination including Phalen testing and carpal compression testing. In addition, 211 of the 290 joints underwent electrodiagnostic testing by the end of this study. Among the 211 joints for which electrodiagnosis was used, a chi2 analysis was performed to determine the correlation among subjective swelling, the Phalen and carpal compression tests, and the electrodiagnostically verified carpal tunnel syndrome. Two weeks after splinting, an assessment was made of the subjective response to splinting. Chi2 analysis was then performed to assess the correlation among the Phalen test, carpal compression test, and nerve conduction study results and the symptom of subjective swelling at presentation with that of response to splinting. Subjective swelling of the hand showed a trend toward association with electrodiagnostic results (although this finding was not statistically significant) and proved to be significantly correlated with a poor clinical response to splinting. Positive electrodiagnostic findings were significantly, though positively, correlated with pain relief from splinting. This study, therefore, introduces the complaint of subjective swelling of the affected hand as an important diagnostic and prognostic symptom for the assessment and treatment of carpal tunnel syndrome.

Carpal Tunnel Syndrome↗
PubMedDate not supplied

Dosing practices of physicians for anticoagulation with warfarin during inpatient rehabilitation.

OBJECTIVE: To determine the percentage of international normalized ratios (INRs) maintained within the therapeutic range for patients receiving chronic anticoagulation treatment with warfarin during inpatient rehabilitation. DESIGN: A consecutive, 4-month, retrospective chart review of all patients receiving oral anticoagulation treatment was conducted in a large academic rehabilitation center. The percentage of INRs within and out of the therapeutic range, frequency of blood samples, length of therapy, and warfarin dose prescribed by physicians were calculated. A total of 181 patients receiving chronic anticoagulation treatment were identified. A total of 3,709 blood samples were analyzed. In 74 patients, the primary physician recommended a therapeutic range (Group 1). In the remaining 107 patients, no therapeutic range was specified, and a target INR range of 2.0-3.0 was assumed (Group 2). RESULTS: In Group 1, the INRs were in the recommended range in 38.2% of all blood samples. In Group 2, 37.6% of all blood drawn was within an INR range of 2.0-3.0. Statistical analysis showed that no better accuracy was obtained when the INR range was predefined by a physician (Group 1) or assumed to be in the 2.0-3.0 range (Group 2; P = 0.839). CONCLUSIONS: Despite frequent physician monitoring, this study demonstrates the difficulty in maintaining INRs within therapeutic ranges for patients receiving oral anticoagulation. An overall tendency for underdosing is observed. Improvement is necessary, given the high morbidity and mortality associated with insufficient anticoagulation in rehabilitation inpatients.

Anticoagulants↗