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2.
Wiad Lek ; 54(1-2): 116-21, 2001.
Artigo em Polonês | MEDLINE | ID: mdl-11344696

RESUMO

A case of anaphylactic shock which appeared in a nurse working at surgery room for many years, was described. The nurse was examined due to the anaphylactic attack at work (paroxysmal, idiopathic anaphylaxis). Among many factors the first of all occupational ones (exposure to disinfectants, latex and penicillin) were taken into consideration. Two minutes after the intradermal application of 2 units of crystalline penicillin the symptoms of anaphylaxis (including the shock) occurred. The problems of penicillin allergy in the aspect of skin tests, which make use of this antibiotic, were also described in the paper.


Assuntos
Anafilaxia/induzido quimicamente , Hipersensibilidade a Drogas/diagnóstico , Doenças Profissionais/diagnóstico , Penicilinas/efeitos adversos , Testes Cutâneos , Adulto , Contraindicações , Hipersensibilidade a Drogas/etiologia , Feminino , Humanos , Injeções Intradérmicas , Doenças Profissionais/induzido quimicamente , Enfermagem Perioperatória , Recidiva
3.
Radiat Res ; 155(1 Pt 1): 32-42, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11121213

RESUMO

The RBE of protons has been assumed to be equivalent to that of photons. The objective of this study was to determine whether radiation-induced DNA and chromosome damage, apoptosis, cell killing and cell cycling in organized epithelial cells was influenced by radiation quality. Thyroid-stimulating hormone-dependent Fischer rat thyroid cells, established as follicles, were exposed to gamma rays or proton beams delivered acutely over a range of physical doses. Gamma-irradiated cells were able to repair DNA damage relatively rapidly so that by 1 h postirradiation they had approximately 20% fewer exposed 3' ends than their counterparts that had been irradiated with proton beams. The persistence of free ends of DNA in the samples irradiated with the proton beam implies that either more initial breaks or a quantitatively different type of damage had occurred. These results were further supported by an increased frequency of chromosomal damage as measured by the presence of micronuclei. Proton-beam irradiation induced micronuclei at a rate of 2.4% per gray, which at 12 Gy translated to 40% more micronuclei than in comparable gamma-irradiated cultures. The higher rate of micronucleus formation and the presence of larger micronuclei in proton-irradiated cells was further evidence that a qualitatively more severe class of damage had been induced than was induced by gamma rays. Differences in the type of damage produced were detected in the apoptosis assay, wherein a significant lag in the induction of apoptosis occurred after gamma irradiation that did not occur with protons. The more immediate expression of apoptotic cells in the cultures irradiated with the proton beam suggests that the damage inflicted was more severe. Alternatively, the cell cycle checkpoint mechanisms required for recovery from such damage might not have been invoked. Differences based on radiation quality were also evident in the alpha components of cell survival curves (0.05 Gy(-1) for gamma rays, 0.12 Gy(-1) for protons), which suggests that the higher level of survival of gamma-irradiated cells could be attributed to the persistence of nonlethally irradiated thyrocytes and/or the capacity to repair damage more effectively than cells exposed to equal physical doses of protons. The final assessment in this study was radiation-induced cell cycle phase redistribution. Gamma rays and protons produced a similar dose-dependent redistribution toward a predominantly G(2)-phase population. From our cumulative results, it seems likely that a majority of the proton-irradiated cells would not continue to divide. In conclusion, these findings suggest that there are quantitative and qualitative differences in the biological effects of proton beams and gamma rays. These differences could be due to structured energy deposition from the tracks of primary protons and the associated high-LET secondary particles produced in the targets. The results suggest that a simple dose-equivalent approach to dosimetry may be inadequate to compare the biological responses of cells to photons and protons.


Assuntos
Dano ao DNA , Raios gama/efeitos adversos , Prótons/efeitos adversos , Glândula Tireoide/efeitos da radiação , Animais , Apoptose/efeitos da radiação , Bromodesoxiuridina/metabolismo , Ciclo Celular/efeitos da radiação , Linhagem Celular , Sobrevivência Celular/efeitos da radiação , Cromossomos/efeitos da radiação , DNA/efeitos da radiação , Relação Dose-Resposta à Radiação , Células Epiteliais/citologia , Células Epiteliais/efeitos da radiação , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Ratos , Ratos Endogâmicos F344 , Eficiência Biológica Relativa , Glândula Tireoide/citologia
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