Biomedical subjects

A Tormo

Publications and source records attributed to A Tormo.

23 records · Page 2Linked to original sources

PubMed1984

Co-ordination between elongation and division in Escherichia coli mediated by the wee gene product.

A procedure to construct strains of Escherichia coli containing conditional lethal mutations in two different genes was used to construct a ftsA-3(ts) wee(Am) supF(ts) strain. This strain, OV-25-7, was used to ascertain whether the wee gene product (Wee) acts at the level of regulation of cell elongation or at the co-ordination of elongation and division. The mass per unit length and the buoyant density of cells in the absence of Wee increased only if division was allowed, as in the case of strain OV-25 (wee(Am) supF(ts)), but not when it was inhibited, as in strain OV-25-7. These results suggested that in E. coli the wee gene product was acting at the level of coordination between elongation and cell division.

Cell Cycle↗

PubMed1984

The ftsA gene product participates in formation of the Escherichia coli septum structure.

The patterns of septation in filaments of Escherichia coli, formed as a consequence of the lack of an active ftsA gene product and then returned to permissive conditions, were analyzed in isogenic strains containing three different mutated alleles of ftsA. Septation was blocked for at least one doubling time at the potential septation sites that presumably contained inactive FtsA protein but not at those sites containing either the active gene product or no gene product at all. These results suggested a possible structural role for the ftsA gene product in the construction of the E. coli septum.

Alleles↗

PubMed1981

[Treatment of Ewing's sarcoma with special reference to radiotherapy].

The authors study 31 cases of Ewing's sarcoma. The survival after 5 years in only 25% for the initially localized tumors because lung and bone metastases finally develop in spite of any treatment. Polychemotherapy defers the appearance of metastases and increases the number of survivors. Patients being less than 15 years old offer a worst prognosis. The tumor localization, existence of general symptoms and their duration, and the alterations of the blood picture were not related with significant variations in the evolution of the Ewing's sarcoma in the studied cases. Probably the prophylactic irradiation of the lungs delays the appearance of metastases.

Adolescent↗

PubMed1980

Involvement of the ftsA gene product in late stages of the Escherichia coli cell cycle.

Strain D-3 was shown, by genetic complementation with lambda phage vectors carrying either the wild type or a temperature-sensitive allele, to contain an ftsA mutation. The presence of this mutation rendered the strain unable to divide at 42 degrees C. The action of the ftsA gene product in strain D-3 takes place at a late stage of the cycle, starting near the end of the replication cycle and extending until cell division is completed. The action of the ftsA gene product seemed to take a constant time, independent of the duration of the cell division cycle. Experiments in which all other requirements for division except a "termination protein" were completed show that cells of strain D-3 can divide under these conditions only at the permissive temperature. We conclude that a likely role for the ftsA gene product is that of a termination protein.

Bacterial Proteins↗

PubMedDate not supplied

[Pre-operative radiotherapy, conventional or accelerated, for invasive bladder cancer. Objectives and radiation modalities. Results and complications].

OBJECTIVE: To present the experience of La Fe Hospital and the Institute of Oncology of Valencia with preoperative radiotherapy for bladder cancer and review the literature. METHODS: The principles of radiotherapy are discussed and the most important series reported in the English literature (Memorial Sloan Kettering, M.D. Anderson, London Institute of Urology and Rotterdam Radiotherapy Institute) and the largest published Spanish series (Ramón y Cajal Hospital) are reviewed. Furthermore, the results achieved in 123 patients treated between 1982 and 1989 at the Urology and Radiotherapeutic Oncology services of La Fe Hospital and the IVO experience with accelerated radiotherapy (20 Gy in 5 fractions) immediately followed by radical cystectomy are presented. RESULTS: The five-year survival ranged from 39% to 66%. Distant metastasis, which occurred in more than 50% of the patients, was the most common cause of failure. Comparison of the complication rates of the different series is difficult to perform. The operative mortality ranged from 2.4% to 10% and was 8% in our series. Preoperative radiotherapy does not appear to increase the number of postoperative complications. By multivariate analysis, lymph node involvement was the only significant factor that influenced survival in our series. CONCLUSIONS: It cannot be concluded from the analysis of the prospective and randomized studies that preoperative radiotherapy improves survival in patients with invasive bladder cancer. However, some authors have reported that patients with T3b tumor might benefit from this therapeutic modality.

Female↗