Biomedical subjects

A Lieber

Publications and source records attributed to A Lieber.

5 recordsLinked to original sources

PubMed1992

Stimulation of cell division and fibroblast focus formation by antisense repression of retinoblastoma protein synthesis.

Circumstantial evidence supports a role for the retinoblastoma susceptibility gene, Rb-1, in the maintenance of normal cell growth, in that loss of its function results in abnormal growth and malignancy. Here we report that a high rate of mitosis and efficient dense focus formation in human embryonic lung fibroblasts (HEL cells) is induced by antisense oligonucleotide-directed inhibition of synthesis of p105-Rb, the product of the Rb-1 gene. mRNA specific for p105-Rb is truncated at the site of base pairing with the antisense oligonucleotide, and no synthesis of p105-Rb is observed. The rate of mitosis is considerably increased and the frequency of dense focus formation is extremely high in treated cells. However, although phosphothioate oligodeoxyribonucleotides taken up by the cells remain stable for at least 4 weeks, the recipient cells do not become immortal; nor are they able to induce tumor formation in nude mice. Thus, loss of Rb-1 function is not sufficient per se to allow malignant transformation.

Base Sequence↗

PubMed1991

Functional significance of sequences following the TATA box of an immunoglobulin promoter studied by random mutagenesis.

We have investigated the importance of sequences downstream to the TATA box of an immunoglobulin promoter by transfection and in vitro transcription assays. A sequence from -11 to +10 with respect to the transcriptional start site was synthesised by a procedure allowing for random misincorporation of nucleotides. The pool of mutant oligonucleotides was cloned into the respective position of a vector carrying a fusion of a synthetic immunoglobulin heavy chain promoter with the human growth hormone gene. From 200 clones sequenced, 115 were mutants with at least one nucleotide exchange in every position. Whereas most mutations are of minor functional importance, changes at or near the transcriptional start site reduce the promoter activity considerably.

Base Sequence↗

PubMed1991

Using comparative clinical information to understand practice patterns and affect organizational change.

The University Hospital Consortium is collecting clinical, administrative and financial data from its members to develop a Clinical Information Network. The value of this collective data lies in how comparative information about peer hospitals and physicians in the same specialty can be used to influence practice. The raw data from each hospital is analyzed, classified, normalized and stored in a data repository which is easily accessible. This data becomes information when it is presented in a variety of ways, and is supported by a knowledge-base of health care rules. The "drilling down" technique to progressive levels of detail serves the needs of all levels in the organization--executives, managers, and analysts. The system combines the power of a mainframe for the data repository with the ease of use of a PC-based workstation. With an open-ended approach, the users can ask a variety of questions of the data, as well as perform statistical analysis, create graphical presentations and generate explanations of the analysis techniques.

Artificial Intelligence↗

PubMed1976

Generalized osteoblastic bony metastases from medulloblastoma.

Osteoblastic bony metastases were observed in a case of medulloblastoma three years after surgery and radiation treatment. There was clinical response to COP therapy (cytoxin, oncovin, prednisone). Radiographic and isotopic bone scan study showed uniform increase in bone density. Serum calcium and phosphorous and acid phosphatase levels were normal. Alkaline phosphatase was elevated and declined with therapy without change in the bone appearance. This suggested an increase in bone deposition activity. However, no increase in calcitonin level was detected either during active disease or following a chemotherapy-induced remission.

Adult↗

PubMed1975

Rectal diverticula.

Eight cases of rectal diverticula are discussed with reference to the etiological, clinical and radiological findings. Males predominated 3:1 and the average number of diverticula in each patient was 2. Diverticulosis of the remaining colon, especially the sigmoid segment, always accompanied rectal diverticula. The average diameter of rectal diverticula was larger than that of the colonic: 2.5 cm vs. 0.5-1.0 cm. Rectal diverticula may be confused with a carcinoma at endoscopy. Surgical treatment becomes necessary if the diverticulum progresses to abscess formation and perforation.

Aged↗