X-Autosom-Translokation bei einem Kind mit multiplen Mißbildungen

In an infant with multiple malformations (microcephaly, deformities of the skull, malformation of the eyes, skeletal abnormalities, inquinal hernias, malformation of the heart, severe mental retardation) we found within a modal number of 45 chromosomes one extra chromosome of a particularly large shape. On the other hand two chromosomes of the C-group were missing. Since there is agreement between the autoradiographic results in blood culture and the sex-chromatin findings we assume a partial translocation of a C-group chromosome to a X-chromosome. Whereas this X-chromosome shows a late DNA-replication pattern and seems to be inactivated, the translocated part of the autosome is not involved into the replication process of the gonosome; hence does not seem to be inactivated. The cytogenetic findings and their relation to the hypothesis of LYON are discussed. In comparing these findings with the observed X-autosomal translocations in mice discretion is indicated. In this study the inactivation of the X-chromosome seems to remain without influence on the translocated part of the autosome. The phenotypic appearance of the child with multiple abnormalities is due to the deletion of the C-group chromosome (C'?), which is affected by the translocation. Anamnestic data indicate that preconceptional exposure of the paternal gonads to X-rays may have caused the chromosomal aberration.     

Comparative study of the asparagine-linked oligosaccharide structures of normal and acute-phase rat plasma thiostatin

Rat plasma thiostatin is a 68 kDa glycoprotein with kinin donor and cysteine proteinase inhibitor properties. Thiostatin is an acute-phase plasma protein (APPP) with dramatically elevated plasma levels in response to inflammatory stimuli. APPPs have been shown to possess altered glycan structures in inflammation. This study compares the carbohydrate structure of normal thiostatin with that expressed during the acute-phase response. Thiostatin from both normal and acute-phase plasma was purified by carboxymethyl-papain Sepharose 4B affinity chromatography. Sugar composition analysis by gas chromatography and the Warren method yielded similar mean values for both proteins on a mole sugar per mole protein basis (normal/acute phase): fucose, 2.4/1.7; mannose, 7.5/8.0; galactose, 11.2/10.6; and sialic acid, 14.2/13.0. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot identified a homogeneous 68–70 kDa molecular species for normal and acute-phase thiostatin. Inter-sugar linkage analysis was carried out for permethylated oligosaccharides released by hydrazinolysis. Gas chromatography yielded the following partially methylated alditol acetates relative to 1.0 mole of 1,3,6-tri-O-linked mannose (mean normal/mean acute phase): galactose: 1,3-di-O-, 1.44/1.01; 1,6-di-O-, 1.02/0.68; mannose: 1,2-di-O-, 1.64/1.42; 1,2,4-tri-O-, 0.24/0.13; 1,3,6-tri-O-, 1.0/1.0; 2-deoxy-2-N-methylacetamidoglucose: 1,4-di-O-, 1.42/1.12. These analytical studies indicated that corresponding carbohydrate structures are present in normal and acute-phase thiostatin. Crossed affinoimmunoelectrophoresis (CAIE) further confirmed the structural similarity between the glycan moieties.     

Genomic diversity and antigenic variation of HIV-1: links between pathogenesis, epidemiology and vaccine development

Recent analysis of primate lentivirus genomes indicates that lentiviruses have infected primates for hundreds of years. The pathogenicity of such viruses may fluctuate due to the high evolution rate of some parts of the viral genome. Fixed nucleic acid substitutions in the gag gene appear to be caused by random fixation of selectively neutral mutants, whereas nonrandom fixation of selectively advantageous mutants, as has been observed for MHC molecules and serine protease inhibitors, appears to be operational for some hypervariable env gene regions. The former is characterized by an excess of silent mutations independent of the rate of change, the latter by an excess of nonsilent mutations. This latter type of selection may especially characterize the third variable region of the external HIV envelope (V3), which contains the principal neutralization domain.     

Spectroscopic and surface-analytical characterization of self-assembled layers on Au

Future devices for electronic, photonic or other “intelligent” application involving (bio-) organic materials require nano-fabrication, -manipulation, -patterning and -functionalization techniques. Supramolecular assemblies, aggregates, small molecules and ions have to be controlled with regard to their structure, order and dynamic behaviour down to the molecular or even atomic level.

This contribution summarizes some of our activities aiming at a better understanding of the physical and chemical properties of functionalized and patterned surfaces. We focus on structure/order-property/function relations in such complex systems as interfaces and thin film architectures. Optical techniques (surface plasmon-spectroscopy) as well as surface analytical techniques (cyclic voltammetry and contact angle investigations) are introduced and demonstrated as powerful tools for the characterization of these interfaces and thin films.

Examples will be given covering self-assembly monolayers and molecular recognition—as well as complexation-reactions.     

Testing Functional Hypotheses for the Behavior of Resident Pine Voles, Microtus pinetorum, Toward Non-Residents

Members of a social group should attempt to maximize their fitness by maintaining an optimal group composition. Allowing an immigrant into the group may be beneficial or costly depending on the characteristics of the immigrant as well as the composition of the group. Therefore, we examined behavioral interactions between pine voles to test three functional hypotheses proposed to explain behavior of residents toward non‐residents: the resource defense, mate defense, and benefit of extra‐pair copulation hypotheses. To test these, we examined the effects of age, sexual experience and sex of non‐residents as well as the effects of sex of residents on the behavior of residents. Neither male nor female residents showed affiliative behavior toward non‐residents. Residents were more aggressive toward non‐residents than vice versa. The frequency of same‐sex aggression was greater than opposite‐sex aggression for male residents and this aggression was directed at adult male non‐residents to a greater degree than at subadult males. Resident males were least aggressive toward adult females. We found no differences in the behavior of females toward subadults, sexually naive adult non‐residents or sexually experienced adult non‐residents. Females also displayed similar amounts of aggression toward male and female non‐residents. Therefore, for males, aggression may function in defense of a mate while for females, aggression functions in resource defense. For both sexes, aggression is likely to play a role in the regulation of group composition.