Possibilities of extraction and characterization of ancient plasma proteins in archaeological bones

Due to the mineral matrix bone proteins are capable of surviving during centuries after inhumation, but cross-linking with other bone proteins as well as fragmentation and complex reactions with humic acids and microorganisms lead to considerable alterations in molecular weight and structure of these proteins. Our group concentrates on polymorphic plasma proteins which diffuse out of the capillary system into the bone matrix where they adsorb to the mineralic substrate. So far, only little is known about the degradation and alteration of these proteins in fossil bones. It has to be evaluated whether the aged proteins still contain some of the information which renders them a valuable tool for forensic questions and population genetics in recent populations. Therefore we tried by modification of already existing methods to expand plasma protein identification and subtyping into the new field of aged plasma proteins.     

Biochemical and palaeopathological investigations on weaning and infant mortality in the early Middle Ages

Weaning age of the children of the early medieval population at Wenigumstadt (Ldkr. Aschaffenburg, southern Germany, 500-700 AD) was estimated by stable nitrogen isotope analysis of bone collagen. The onset of weaning was by one year of age, when solid vegetal food subsequently replaced breast milk. In total, the change from mother's milk to solid adult food took about three years, the infants being fully weaned at this age. While the growing infant was sufficiently supported in utero and during the first months of life, the weanling's diet was insufficient for further growth and development. Starting with about 18 months of age, more and more symptoms of malnutrition are detectable on the skeletal remains, and the peak of both morbidity and mortality is reached at four years of age. Especially unspecific stress markers like Harris' lines and enamel hypoplasia clearly indicate the infants' risk of falling ill or die between three and four years of age. Malnutrition weakens the immune response, therefore the majority of inflammations detectable on the skeleton are found among the inadequately nourished children. The assumption that weaning is responsible for pathological skeletal lesions and early death in history is thus supported by archaeometry.     

Local or nonlocal? A research of strontium isotope ratios of teeth and bones on skeletal remains with artificial deformed skulls

The analysis of strontium isotopic composition of teeth and bone served as an approach to determine nonlocal individuals with artificially deformed skulls in Teuton and Gepid sites. A differing Sr-isotopic composition between tooth and bone from the same skeleton reveals a residence change between early childhood and the last ten years before death. The results show that most Teuton and Gepid individuals investigated are local habitants.     

Novel hydroxycarotenoids with improved antioxidative properties produced by gene combination in Escherichia coli

We have used combinatorial biosynthesis to synthesize novel lipophilic carotenoids that are powerful cellular antioxidants. By co-expressing three different carotenoid desaturases in combination with a carotenoid hydratase, a cyclase, and a hydroxylase on compatible plasmids in Escherichia coli, we synthesized four novel carotenoids not previously detected in biological material or chemically synthesized. Their identification was based on their relative retention times on HPLC, spectroscopic properties, molecular weights, number of hydroxy groups, and 1H-NMR spectra. The carotenoids were designated as 1-HO-3', 4'-didehydrolycopene, 3, 1'-(HO)2-gamma-carotene, 1,1'-(HO)2-3, 4, 3', 4'-tetradehydrolycopene, and 1, 1'-(HO)2-3, 4-didehydrolycopene. These novel acyclic derivatives differ from structurally related compounds by extension of the conjugated polyene chain as well as additional hydroxy groups at position C-1'. We determined their antioxidative activity in a liposome-membrane model system, which showed that their ability to protect against photooxidation and radical-mediated peroxidation reactions was linked to the length of the conjugated double-bond system and the presence of a single hydroxy group. The protection of membrane degradation was superior to the related 1-HO and 1, 1'-(HO)2 lycopene derivatives, making them interesting pharmaceutical candidates.     

The analysis of oligonucleotide preparations by fractal measures

In this paper we put forward improved mathematical methods for detecting synthesis parameters in connection with analyzing crude products of chemically synthesized oligonucleotides. The crude products experimentally sampled are separated by high-performance capillary electrophoresis and ion-exchange high-performance liquid chromatography. The measured separation profiles of experimental syntheses can be expressed as target and nontarget yields; they are characterized by a few parameters. These parameters account for nonlinear synthesis equations that are solvable by employing iteration procedures. We provide here a theoretical as well as computational analysis based upon specific models for stepwise chain growth. Under nonconstant (nonuniform) conditions we use here an exponential form of growth, with different expressions for calculating the fractal dimension of the biochemical process under study. Step lengths of parameter variations in an interval of finite length have to be adjusted properly to find convergent solutions in a mathematical, regularly four-dimensional parameter space. It is conceivable to have most, if not all, of the calculating and plotting carefully done by a computer. This analysis represents the experimental situation up to 65-mer target oligonucleotides analyzed so far. We thus obtain the dynamics of the polymerization process limited in number by fractal models. The advantage, calculating these new methods as compared to qualitatively judged experimental methods, lies in the satisfactory evaluation of crude products, also of large amounts, of syntheses of these biopolymers. © 1998 John Wiley & Sons, Inc. Biopoly 45: 361–379, 1998     

Selective inhibition of leukotriene receptor BLT-2 reduces vascular oxidative stress and improves endothelial function in ApoE?/? mice

Atherosclerosis is a chronic inflammatory disease and represents the main cause of death in the industrialized world. Metabolites of the arachidonic acid derived from the 5-lipoxygenase pathway are known as leukotrienes that mediate various inflammatory processes during atherogenesis. Leukotriene B4 elicits the overexpression of several proinflammatory proteins, promotes chemotaxis and foam cell formation via BLT receptors. Currently, little is known about the implications of the BLT2 receptor in atherogenesis. Here, we tested whether selective inhibition of this receptor influences the progression of atherosclerosis in mice. Apolipoprotein-E deficient mice were fed a high-fat, cholesterol-rich diet to create atherosclerotic conditions (each group n?=?9). Simultaneously, mice received the pharmacologic BLT2 inhibition (Ly) by intraperitoneal injection every second day 5?mg/kg bw or vehicle. After 8 weeks, mice were killed and experiments were performed. Vascular superoxide release was diminished in mice treated with Ly compared with the control group (68?±?15 vs 131?±?20 RLU, P?=?0.01), as measured by L012 assay. Next, endothelial function was assessed by organ chamber experiments. Endothelial-dependent relaxation was improved in mice treated with the BLT2 receptor antagonist. To determine whether selective inhibition of the BLT2 receptor affects the atherosclerotic plaque growth, immunohistochemical stainings of the aortic root were performed. Oil red O staining revealed no significant differences between both groups (36?±?3% vs 38?±?3%). Monocyte infiltration into the vessel wall was analyzed using Moma-2 staining. No significant differences were observed between both groups (31?±?3% vs 34?±?2%). Selective inhibition of the BLT2 receptor in mice reduces the release of vascular reactive oxygen species and improves endothelial function in mice. Further experiments are necessary in order to obtain tissue-specific and mechanistical insights.