Cytokinetic effects of interferon in colorectal cancer tumors: implications in the design of the interferon/5-fluorouracil combinations.

Interferon (IFN) has been shown to enhance the cytotoxic effects of 5-fluorouracil (5FUra) in colorectal cancer, and clinical trials with this combination resulted in higher response rate with respect to 5FUra alone. IFN is generally administered s.c. three times a week. This prolonged exposure could determine a block of tumor cells in the G0-G1 phase of the cell cycle, thus rendering tumor cells insensitive to 5FUra, an S-phase specific agent. In order to verify the presence of this block, 21 operable colorectal cancer patients were treated with IFN-alpha 2b at the dose of 3 megaunits every other day in the week before operation, while another 22 represented the control group. Samples of tumor tissue were taken at endoscopy and operation. [3H]Thymidine labeling index and flow cytometry were used to assess the S-phase fraction. In IFN treated patients, we found a significant statistical difference between the mean percentage of S-phase fractions evaluated either by labeling index (P = 0.00001) or by flow cytometry (P < 0.001). On the contrary, this difference was not present in the control group: labeling index, P = 0.06; flow cytometry, P = 0.08. Furthermore a significant increase in the G0-G1 phase of the cell cycle was found after IFN administration (P < 0.001) but not in the control group. Our results suggest that IFN reduces the S-phase fraction in colorectal cancer tumors. This action should be considered in the design of the 5FUra/IFN combination because it could decrease 5FUra activity, leading to a loss or a decrease in the advantage of 5FUra modulation by IFN.

[Statistic relation between seropositivity to Toxoplasma gondii and several risk factors in a sample of pregnant women]. / Relazione statistica tra sieropositività a Toxoplasma gondii ed alcuni fattori di rischio in un campione di donne gravide.

We analysed, in the period 1984-1986, the serum of 1733 pregnant women. The relation between the positivities and some probable factors of risk, alimentary habits and touch with tame animals has had valued by statistical method. The analysis shows no increase of risk in the group used to eat underdone meats compared with the group in touch tame animals.

[Comparison between 2 separation methods of IgM and IgG in serologic diagnosis]. / Confronto tra due metodi di separazione delle IgM dalle IgG nella diagnostica sierologica.

The concentrations of the IgG and IgM fractions have been determined on thirty whole sera and after treatment with protein A, or after chromatographic separation. The analysis of the differences has been effected with Student's t test. No statistically significant differences have been noted between the two methods of separation as far as IgM fraction is concerned, but, on the contrary, significant differences are present for the separation of IgG fraction.

[Evaluation of immune status in rubella infection in the pregnant population of the U.S.L. 3 of Pesaro 1981-1985]. / Valutazione dello stato immunitario nei confronti dell'infezione rubeolica nella popolazione gravida del comprensorio dell'U.S.L. 3 di Pesaro negli anni 1981-1985.

The object of this study is an evaluation of the epidemic situation concerning the rubella in the pregnant population of age included between 18 and 40 years of the U.S.L. 3 of Pesaro, in the period 1981-1985. The percentage of seropositivity in an average is around 93.8%; nevertheless such a percentage of seronegativity persists as to justify an intervention of prophylaxis by means of vaccination above all in the age from 18 to 25 years, that represents the 43.8% of the examined sample. It must be pointed out the evolution of the immunity situation from the 36 to the 40 years.