Search PubMed⌕ Search

Biomedical subjects

R L Ellis

Publications and source records attributed to R L Ellis.

At least 19 recordsLinked to original sources
PubMed1992

Identification of a family of bacteriophage T4 genes encoding proteins similar to those present in group I introns of fungi and phage.

The bacteriophage T4 segA gene lies in a genetically unmapped region between the gene beta gt (beta-glucosyltransferase) and uvsX (recombination protein) and encodes a protein of 221 amino acids. We have found that the first 100 amino acids of the SegA protein are highly similar to the N termini of four other predicted T4 proteins, also of unknown function. Together these five proteins, SegA-E (similar to endonucleases of group I introns), contain regions of similarity to the endonuclease I-Tev I, which is encoded by the mobile group I intron of the T4 td gene, and to putative endonucleases of group I introns present in the mitochondria of Neurospora crassa, Podospora anserina, and Saccharomyces douglasii. Intron-encoded endonucleases are required for the movement (homing) of the intron DNA into an intronless gene, cutting at or near the site of intron insertion. Our in vitro assays indicate that SegA, like I-Tev I, is a Mg(2+)-dependent DNA endonuclease that has preferred sites for cutting. Unlike the I-Tev I gene, however, there is no evidence that segA (or the other seg genes) resides within introns. Thus, it is possible that segA encodes an endonuclease that is involved in the movement of the endonuclease-encoding DNA rather than in the homing of an intron.

Amino Acid Sequence↗
PubMed1991

Immunoscintigraphy of colorectal carcinoma utilizing 111In-labeled monoclonal antibody conjugate CYT-103.

Twelve presurgical patients with colorectal carcinoma received a single intravenous infusion of 0.5-20.0 mg of the radiolabeled monoclonal antibody conjugate CYT-103. This product is an immunoconjugate of B72.3 labeled with Indium-111 (111In). Patients underwent preoperative gamma camera imaging and computed tomographic (CT) scanning of the abdomen and pelvis. Fifteen intraabdominal sites of tumor were found at surgery. Monoclonal antibody imaging detected 87% of these lesions, whereas CT of the abdomen and pelvis detected 47%. Monoclonal antibody imaging identified tumor in 27% of the patients in which CT did not identify any sites of tumor. The results of this study indicate that monoclonal antibody imaging using [111In]CYT-103 is useful for the preoperative evaluation of colorectal carcinoma patients and the results are complimentary to CT of the abdomen and the pelvis.

Adult↗
PubMed1989

Implantation techniques: a primary consideration in valve surgery.

Clean site preparation for a prosthesis is mandatory to avoid tissue interference with the prosthesis. Oversizing of a prosthesis is fraught with peril. In all types of prostheses, orientation has importance. A prosthesis is designed with consideration for axial flow. Tilting the valve in implantation will likely result in a dysfunctional valve. The sewing ring serves not as a gasket but as an additional factor that increases the possibilities of success of a properly implanted valve by taking advantage of its naturally compliant features.

Aortic Valve↗
PubMed1989

Sonographic definition of the empty follicle syndrome.

The sonographic definition of the empty follicle syndrome is presented in a group of 89 consecutive, unmedicated menstrual cycles in women with primary or secondary infertility. The incidence of the empty follicle syndrome was found to be 50%. The incidence increased with age and was independent of gravidity or the type of follicular rupture (or lack of rupture). These data suggest that the empty follicle syndrome may represent a significant etiologic factor in infertility or other reproductive abnormalities.

Adult↗