Hydrous oxide formation on gold in base under potential cycling conditions

The formation of hydrous oxide films on gold in base under potential cycling conditions was investigated and found to be less inhibited than the same type of reaction observed when gold is strongly anodized at high potentials under d.c. conditions at high pH. The overall behaviour on cycling is quite similar to that observed with other metals, e.g. platinum. The importance of the lower limit, for instance, again appears to be related to the need under film thickening conditions to significantly reduce the compact oxide layer formed on the metal surface during the anodic sweep. It was noted that the earlier duplex model for this type of system, i.e. an inner compact and an outer dispersed oxide layer, is not always valid. Under certain conditions about six distinct peaks (suggesting six different states of gold oxide hydration, dispersion or polymerization) were observed in cathodic sweeps recorded for the reduction of thick films grown on gold under potential cycling conditions in base.     

Effects of fetal genotype and uterine environment on placental development in equids

Measurement of the concentrations of equine chorionic gonadotrophin (eCG) in the serum of pregnant mares and Jenny donkeys carrying normal intraspecies and hybrid interspecies pregnancies suggested that the production of this hormone may be influenced by parental gene imprinting. Specifically, a differential expression of maternal and paternal genes may control the size and secretory activity of the structures that secrete eCG, the fetal endometrial cups. However, bisection of an interspecies mule embryo followed by transfer of the resulting demi-embryos and other intact mule embryos to horse and donkey recipients resulted in striking differences in the size, secretory activity and lifespan of the endometrial cups in two types of surrogate mother. This finding has therefore demonstrated the ability of uterine factors to alter profoundly the development and characteristic phenotype of the specialized invasive chorionic girdle portion of the equine trophoblast that gives rise to the endometrial cups.     

Endovascular treatment of an external carotid arteriovenous malformation

Herein we describe a case of a hemorrhagic adrenal pseudocyst that had been initially suspected as being a renal adenocarcinoma. The intraoperative anatomopathological study of the specimen permitted performing conservative surgery. The diagnosis and pathogenesis of this uncommon disease entity are discussed.     

New ideas on the pathophysiology and treatment of lung disease

In the present study, the effects of compounds extracted from Tanacetum microphyllum, four flavonoids and one sesquiterpene lactone, on arachidonic acid metabolism in cellular systems were examined. In the PGE2- and LTC4-release assay, most compounds did not exhibit any significant effect. Only hydroxyachillin, and the flavonoids centaureidin and 5,3'-dihydroxy-4'-methoxy-7-methoxycarbonylflavonol showed a significant effect, although with less potency than the reference drugs, indomethacin and NDGA. However, all compounds inhibited the release of TXB2 from ionophore-stimulated human platelets. The action is more marked with the flavonoids santin and ermanin.