Glycidyl azide-r-(3,3-bis(azidomethyl)oxetane) copolymers were synthesized by cationic copolymerization of epichlorohydrin and 3,3-bis(bromomethyl)oxetane, using butane-1,4-diol as initiator and boron trifluoride etherate as catalyst, followed by azidation of the halogenated copolymer. The main objective of this work is the preparation of an amorphous polymer with energetic content higher than that of the well known glycidyl azide homopolymer. The effect of experimental conditions, like i.e. the rate of monomer feeding, on the final molecular weight and functionality of the copolymer has also been investigated. The obtained copolymers were extensively characterized to determine their composition and thermal stability. The heat of reaction for the polymerisation of the halogenated key precursors has also been measured.

Azidated oxetanic polymers such as poly(3‐azidomethyl‐3‐methyl oxetane), are under investigation as “energetic” binder to be used as an alternative to polybutadiene in solid rocket propellants. The classic synthetic route for the production of the polymer is through an azidated monomer where the N3− functionality has been previously introduced by nucleophilic displacement of a suitable, usually a halogen, leaving group. However, this could involve critical steps with manipulation of a highly unstable liquid monomer. Here it is shown that the azidation can be performed as the final step of the preparation by substitution of the tosyl group in a preformed polymer. The procedure assures good yield and purity of the product and satisfactory rate of reaction, being the energetic functionality always kept in a safe form, which shows low shock and friction sensitivity. Poly(3‐azidomethyl‐3‐methyl oxetane) was prepared by azidation of poly(3‐tosyloxymethyl‐3‐methyl oxetane) in dimethylsulfoxide, testing several operating conditions. Moreover, hypothesizing a second order kinetics, the rate constant and the activation energy for the azidation step have been estimated.

SummaryTwo cases of congenital combined deficiency of factor VIII (antihaemophilic globulin) and factor V (proaccelerin) in 2 sibilings (a female and a male) born of non-consanguineous parents are reported.Mild isolate defect of factor V was demonstrated in the mother and in 2 maternal aunts, while pure factor VIII deficiency was found in a male relative on the maternal side.Infusion of normal fresh plasma lead in both cases to a parallel rise of both factors, while infusion of haemophilic plasma lead to a rise of factor V only, thus excluding the presence in the haemophilic plasma of a common precursor to both factors.The genetic study of the family seems to suggest that the two defects are inherited according to different patterns, two genes being responsible for the two defects. Factor V deficiency seems inherited according to an autosomal incompletely dominant type of heredity, while factor VIII deficiency is due to a sex-linked mutant gene.Genie interaction, inversion of the dominance or early inactivation of the normal X-chromosome in a carrier are the possible explanations for the severe factor VIII deficiency in the proposita.

Poly(3-azidomethyl-3-methyloxetane) and its copolymers with 3,3-bis(azidomethyl)oxetane were synthesized by cationic polymerization from 3-tosyloxymethyl-3-methyl oxetane and 3,3-bis(bromomethyl)oxetane, using a polyol as initiator and boron trifluoride complex as catalyst, followed by azidation. The final objective is the synthesis of an energetic binder to be used for rocket propellants and therefore the effects of different initiator/catalyst systems on important properties, like, i.e., the molecular weight distribution and the functionality of the polymer, were investigated. It was found that, even though both the operating conditions and the catalytic system were chosen in order to grant the living character of the polymerization, the latter seems to be prevalently driven by an "active chain end" mechanism. In particular, this may lead to the undesired formation of a small quantity of oligomers and to the presence of non-hydroxylic chain-end functionalities. Nevertheless, the average number of OH groups can be strictly controlled when boron trifluoride tetrahydrofuranate is used as catalyst.

In the solid rocket propellant formulations an important component is the polymeric binder. Actually, the most used binder is hydroxyl‐terminated polybutadiene. However, the research is oriented toward the use of energetic polymers which, in addition to the binder function, should improve the propulsion capability of the propellant. In this respect, good candidates are oxetanic polyethers with azidic functionalities in their side chains. Considering the explosive character of such materials, their synthesis must be designed with attention to the safety of the process. In this note, the preparation of azidic copolymers is described and different synthetic strategies are discussed and compared.

In previous papers, the synthesis and characterization of OH-terminated glycidyl azide-r-(3,3-bis(azidomethyl)oxetane) copolymers (GA/BAMO) and poly-3-azidomethyl-3-methyl oxetane (pAMMO) by azidation of their respective polymeric substrates were described. The main objective was the preparation of amorphous azido-polymers, as substitutes of hydroxy-terminated polybutadiene (HTPB) in new formulations of energetic propellants. Here, the subsequent characterization of both the binders is presented. First of all, several isocyanates were checked in order to optimize the curing reaction, and then two small-scale formulations of a propellant, based on aluminium and ammonium perchlorate, were prepared and characterized. Finally, the mechanical properties and burning rate were compared to those of a similar propellant based on HTPB as binder

A rapid radioimmunoassay for the determination of dehydroepiandrosterone sulphate (DHEA-S) in diluted human plasma is described. The radioimmunoassay is performed using an antiserum to DHEA-3-hemisuccinate-BSA. A charcoal-dextran mixture is used for separation of the bound from the free fraction. The reliability criteria of the method in terms of precision, accuracy, sensitivity and specificity have been evaluated. The mean level of DHEA-S in plasma samples from normal men (age range 24-37) is 241-5+/-72-5 mug/dl. In normal premenopausal women the highest values are in the second third of the menstrual cycle (corresponding to the ovulatory phase). In normal old men (age range 64-86) and in post-menopausal women (age range 55-88) the mean values are, respectively, 51-9+/-33-8 and 53-8+/-34-0. The DHEA-S levels found in several cases of adreno-cortical disorders are reported. In primary adrenal insufficiency and in Cushing's syndrome due to adrenal adenoma or bilateral multinodular hyperplasia low values are found; in Cushing's syndrome due to bilateral adrenal hyperplasia normal values are usually found.

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