RESUMO
The incorporation of labelled precursors of DNA, RNA and proteins in F. cells infected with Coxsackie B4 virus has been traced both in the presence and absence of total histone from nucleated erythrocytes during the infectious process. In comparison with the virus infection alone, the exogenous histone supressed the incorporation of 3H-thymidine in early hours and the incorporation of 3H-uridine and 14C-leucine in the 9th hour after virus infection. The established repression of the incorporation of the labelled precurssors for RNA and proteins correlates with a drop in the order of 90 to 99% in the yield of infectious virus.
Assuntos
DNA Viral , Enterovirus/efeitos dos fármacos , Histonas/farmacologia , RNA Viral , Proteínas Virais , Radioisótopos de Carbono , DNA Viral/biossíntese , Depressão Química , Eritrócitos , Humanos , Técnicas In Vitro , Leucina/metabolismo , RNA Viral/biossíntese , Trítio , Uridina/metabolismo , Proteínas Virais/metabolismoAssuntos
Células Cultivadas , Cromossomos , Tartarugas , Animais , Cariotipagem , Rim/ultraestruturaRESUMO
A quantitative analysis was carried out of structural chromosome aberrations in human perpheral lymphocytes exposed in vitro to 180 kV X-rays or 50 MeV protons. Statistical treatment of experimental findings by least-squares technique showed a regressional relationship between dose administered and yields of various chromosome aberration types. Fitting of the data to four mathematical models indicated, for both radiation types, that two-break aberrations, total number of aberrations and total of breaks are best fitted by the polinomial of second degree Y equals bD + CD-2, while one-break aberrations and number of aberrant cells are best fitted by the model Y equals a + bD. For all chromosome aberration types numerical values of the coefficients in these models are presented.
Assuntos
Aberrações Cromossômicas , Cromossomos/efeitos da radiação , Prótons , Radiogenética , Relação Dose-Resposta à Radiação , Humanos , Linfócitos/efeitos da radiação , Modelos Teóricos , Análise de Regressão , Raios XRESUMO
Based on quantitation of chromosome anomalies observed following in vitro irradiations of human lymphocytes, RGE values were derived for 50 Me V protons relative to 180 kV X-rays. These values indicated 50 Mc V protons to be generally of similar efficiency as X-rays in producing chromosome anomalies in human lymphocytes. However, detailed analysis by types of anomalies observed yielded different RGE values. Thus, 50 Me V protons were found to be 15 percent less efficient than X-rays in producing two-break exchange type aberrations. And inversely, they were about 15 percent more efficient in producing onebread types of aberrations.
