False-negative prenatal exclusion of Wiskott-Aldrich syndrome by measurement of fetal platelet count and size

The study of the fetal platelet count and size can, according to the literature, be used for the prenatal diagnosis of the Wiskott-Aldrich syndrome (WAS). So far, no affected fetuses have been identified by this method. All pregnancies in which this method had been applied to resulted, as correctly predicted, in the birth of normal children. Here we report on a familial case of WAS where the haematological parameters failed to reveal the affected second child. Hence we assume that the platelet count and size of platelets remain normal in fetuses with WAS to the gestational age of 22 weeks and cannot be used for prenatal diagnosis.     

Cleft palate: Confirmation of prenatal diagnosis by colour Doppler ultrasound

We present a case of a twin with trisomy 47,XX+i(9p) in whom the diagnosis of cleft palate was confirmed by colour Doppler imaging demonstrating abnormal fluid flow across the fetal pharyngeal bone defect. Application of this technique in cases predisposed for this congenital lesion may prove beneficial in the diagnosis of the more subtle types of isolated cleft palate.     

Metallsorption an Illit und Metallfreisetzung unter Einwirken der Aminosäuren Glycin und Histidin

The heavy metal ions Zn(II), Pb(II), Cr(III) and Hg(II) were examined in regard of their adsorption behaviour towards Kaolin W from Lohrheim (51% illite, 31% kaolinite and 18% quarz). By means of the Langmuir and Freundlich models the determined adsorption isothermes could be linearized. The ability of glycine and histidine solutions to release heavy metal ions, pre-adsorbed on Kaolin W (36,1–2300 mg kg^?1 Zn, Pb, Cr and Hg), was specified. It was found a low influence of glycine, but an evident influence of histidine to the metal release, expecially of Pb and Cr, depending on the metalcoating, metal-amino acid-ratio, experimental pH and testing period. The highest remobilisation fraction, up to 98%, could be found in the case of Zn. This elucidates an enhancement of the zinc release compared with the blank solution, without containing amino acids, to a factor of maximal 9,3. As far as Pb and Cr were concerned the histidine extraction exeeded the remobilisation in the blank solution by a maximum of 50,8 or 40. As Hg develops strong covalent bondings to illite by OH-bridges, the release of Hg was not affected by the amino acids.     

Evolutionary aspects of perfume collection in male euglossine bees (Hymenoptera) and of nest deception in bee-pollinated flowers

Summary A fascinating pollination system has been evolved between perfume producing flowers and perfume collecting male euglossine bees in the neotropics. Detailed investigations have contributed to an understanding of the interactions between euglossine males and flowers as a pollination system. The role which the collected perfume plays in the reproductive behaviour of euglossine bees is not fully understood. A favoured hypothesis suggests that the collected fragrances are used as precursors for male sex pheromones and thus serve to attract conspecific males or females. It is not known how perfume collection behaviour evolved. Here, an evolutionary approach presents a new hypothesis which suggests that the evolution of perfume collection in euglossine males is based upon pre-existing signals which were attractive to females and males. It is further suggested that, at the evolutionary outset, flowers mimicked nest sites to deceive nest-seeking euglossine bees. In addition, a comparative study was undertaken on the phenomena of nest-mimicking flowers in related bee families.