Enzo Lencioni

Colorectal administration of human interferon-α

Abstract The possibility that human interferon-α may be absorbed by the colorectal mucosa has been evaluated in the rat. Suppository bases per se do not allow interferon absorption as it was undetectable in peripheral plasma. Inclusion of physiological amounts of Na-ursodeoxycholate favours some interferon absorption although plasma levels remain at a much lower level after comparative subcutaneous administration. Although the results are encouraging, we have been unable to achieve a marked increase of interferon levels in the portal blood that may render rectal administration a selective route in the treatment of hepatitis.

Enteric absorption of human interferons α and β in the rat

Abstract The absorption of both human lymphoblastoid interferon α and natural interferon β from the large intestine has been evaluated in the rat. We have shown that the addition of Labrafil R.M.1944 to the citrate buffer containing interferon α favours its absorption through the enteric mucosa in a significant way while it has practically no beneficial effect for interferon β. It appears worthwhile to pursue this line of investigation because the enteric route may enlarge the field of therapeutic application of interferon.

Performance qualification of a HEPA filter at high temperature

Abstract The authors propose a method for the control of the filtering characteristics of high-efficiency particulate air (HEPA) filters set up in the sterilization tunnels at a temperature of 300 °C and beyond, corresponding to the operating conditions. In the present work the HEPA filter efficiency has been evaluated both with oily aerosol of bis(2-ethylhexyl)sebacate and with pre-calibrated barium sulphate particles. The former was used at room temperature, while for the latter also the working temperature of the sterilization tunnel was employed. Furthermore, attention was given to the airborne particulate cleanliness classes of the filtering characteristics of HEPA filters at high temperature. The results obtained in the present investigation confirm the practicability of our method to evaluate the filtering characteristics at the working conditions, primarily during the performance qualification steps.