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R A Gomes

Publications and source records attributed to R A Gomes.

28 records · Page 2Linked to original sources
PubMed1979

Liquid holding recovery in E. coli K12. I - Substances released during buffer holding.

It is known that the incubation, in a buffer, of UV-irradiated E. coli cells results in viability increase, this phenomenon had been called liquid holding recovery (LHR). We have studied the cellular constituents release during LHR and verified that releasing rate is dose-dependent. LHR was also observed after nitrogen-mustard treatment and it is not blocked by caffeine. So, we suggest that LHR expression is not always a rec-gene dependent function and, probably, the survival increase could be explained by (a) DNA-repair, (b) reversible membrane damage and (c) cellular multiplication.

Buffers↗
PubMed1979

Liquid holding recovery in E. coli K12. II. Role of cellular multiplication.

When UV-irradiated, wild-type E. coli cells are incubated in buffer before plating, consequent survival increases cannot be explained by repair mechanisms alone. Regardless of UV-dose, survival after 48-hours incubation reaches a "plateau" at 10(-1) survival level. An important fraction of the irradiated cells is capable of multiplying during buffer incubation, and the same phenomenon is observed with unirradiated E. coli whenever culture concentration is lower than 10(7) cells/ml. Protein contents per viable cell decreases significantly during buffer incubation. A similar phenomenon was observed in an excision deficient strain. Macromolecule biosynthesis was also observed during buffer incubation. We conclude that, under most experimental conditions, cellular multiplication plays a very important role in liquid holding recovery experiments.

Bacterial Proteins↗
PubMedDate not supplied

[Monitoring AIDS patients for the development of cytomegalovirus (CMV) disease using multiplex PCR].

The human cytomegalovirus is an important pathogen in patients infected with the human immunodeficiency virus (HIV). The CMV viral load seems to be predictor of the development of the CMV disease in these patients. We used a multiplex PCR protocol that also provides quantitative information in those samples from which a single band is amplified and contains fewer viral genomes than those from which both targets are amplified. Monthly blood samples were collected from 270 AIDS patients. From twenty patients, two CMV targets were amplified three or more consecutive times and these patients developed CMV related disease during the study. In contrast, patients who did not result positive for both viral targets, for three or more consecutive times, or who had alternating positive and negative samples during the follow up did not present CMV related disease. The results suggest that the PCR multiplex can be used for the identification of HIV positive patients with higher risk of development of CMV disease.

Acquired Immunodeficiency Syndrome↗