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M Pizzichini

Publications and source records attributed to M Pizzichini.

At least 109 records · Page 6Linked to original sources
PubMed1984

[Biosynthesis of purine nucleotides in the rat muscle after castration].

The paper describes the effects of castration on formate-14C incorporation into the acid-soluble purines and into the nucleic acids of skeletal muscles (ELD and G) and perineal muscle (LAM). 20% homogenates were prepared in 1 M HC10(4), centrifuged and the nucleic acid were extracted from the precipitate with 0.7 N PCA (15 min at 90 degrees C). The acid-soluble purines were precipitated with 1 M AgNO3 from the supernatant of the centrifuged homogenate, then extracted with 1 M HC1 and separated by ion exchange chromatography with a scalar gradient of HC1. In the LAM a significant decrease in the specific activity of the purine bases (A, -56%, P less than 0.01; G, -47%, P less than 0.05) and of the nucleic acid (-47%, P less than 0.01) was observed after castration, while no difference was observed in skeletal muscles.

Adenine↗
PubMed1984

[Effect of castration on purine biosynthesis in the rat liver and kidney].

With the present study, the effects of testosterone deficiency on the biosynthesis of purine nucleotides and nucleic acids in rat liver and kidney has been investigated. 20% homogenates were prepared in 1 N HCl04, centrifuged and the nucleic acid were extracted from the precipitate with 0.7 N PCA (15 min at 90 degrees C): the acid-soluble purines were precipitated with 1 M AgNO3 from the supernatant of the centrifuged homogenate, then extracted with 1 M HC1. An increase of the specific activity of the liver (A, +49%; G, +47%) and of the kidney (A, +54%; G, +34%) has been observed (P less than 0.05), while no variation of the specific activity of nucleic acids was evident after castration.

Adenine↗
PubMed1978

Non-isothermal potential of phospholipid bilayer films. Influence of cholesterol and macrocyclic carrier effects.

The effect of cholesterol on the ion selective behavior of phoshpolipid (phosphatidylcholine or phosphatidylethanolamine) bilayer films is studied through the measurement of the membrane non-isothermal potential. It is shown how the mixed phosphatidylcholine-cholesterol membrane can be either cation of anion permselective according to the film composition (cationic behavior is met in the 0--10% cholesterol composition range while anionic selectivity appears in the 20--50% range). On the contrary, mixed phosphatidylethanolamine-cholesterol membranes show the absence of ionic selectivity already met with pure phosphatidylethanolamine films. The presence of a cationic carrier as Dibenzo-18-crown-6 in the film transforms all the studied films (cationic, anionic and no selective bilayers) into ideally cationic selective membranes. These results are discussed on the basis of the current ideas on the charge distribution through the bilayer membranes. Moreover, the role of the permeating ions as potential determining species is stressed.

Cholesterol↗