Novel mono- and dicationic pyrimidinic surfactants are synthesized and their aggregation behavior is studied by methods of tensiometry and nuclear magnetic resonance (NMR) self-diffusion. To estimate their potentiality as gene delivery agents, the complexation with oligonucleotides (ONus) is explored by dynamic light scattering (DLS) and zeta-potential titration methods and ethidium bromide exclusion experiments. Bola-type pyrimidinic amphiphile (BPM) demonstrates rather a weak affinity to ONus. Although it induces mixed associations with ONus, only slight charge compensation changes occur at a large excess of bola, with no recharging reached. Similarly, the ethydium bromide exclusion study reveals a slow increase in the binding capacity toward an ONu with an increment in BPM concentration. The monocationic pyrimidinic surfactant (MPM) and its gemini analogue (GPM-1) are ranked as intermediates in both their aggregative activity and complexing properties toward ONus. They both form mixed associates with ONus well below the critical micelle concentrations (cmcs) of 2 and 15 mM respectively. However, GPM-1 has a much lower isoelectric point at the molar ratio surfactant/ONu r~1 compared to r~3 for MPM. This probably indicates a larger electrostatic contribution to the ONu complexation in the case of GPM-1. The most hydrophobic pyrimidinic surfactant (GPM-2), bearing three alkyl tails, demonstrates enhanced aggregative activity and binding capacity toward ONus as compared to former pyrimidinic surfactants. Due to effective aggregative (low cmc of 0.04 mM) plus binding properties (fraction of bound ONu β=0.76 at r=2.5), GPM-2 may be ranked as a promising agent for wider biological applications.

Mixed association of calix[4]resorcinarene with ethyl sulfonate groups on the lower rim and dimethylaminomethyl groups on the upper rim (CR) and cationic surfactant 4-aza-1-hexadecyl-azoniabicyclo[2.2.2]octane bromide (DABCO-16) is studied by methods of tensiometry, conductometry, potentiometry and NMR spectroscopy at fixed CR concentration and varied surfactant concentration. Beyond ca. 0.4 mM of DABCO-16, mixed aggregates enriched by CR are proved to be formed due to electrostatic forces, while beyond ca. 5 mM, aggregates enriched by surfactant occur due to the hydrophobic effect. Spectrophotometry monitoring of the solubilization of a hydrophobic dye, Orange OT, demonstrated that only the second type of mixed aggregate enriched by DABCO-16 is capable of binding the organic probe, while the mixed system where the surfactant is a minor component shows no binding capacity towards Orange OT. This finding can be used for the design of nanocontainers with controllable binding/release properties.

New data on the concentrations of key fission/activation products and transuranium nuclides in samples of soil and water from the Semipalatinsk Nuclear Test Site are presented and interpreted. Sampling was carried out at Ground Zero, Lake Balapan, the Tel'kem craters and reference locations within the test site boundary well removed from localised sources. Radionuclide ratios have been used to characterise the source term(s) at each of these sites. The geochemical partitioning of plutonium has also been examined and it is shown that the bulk of the plutonium contamination at most of the sites examined is in a highly refractory, non-labile form.

This population study has examined the incidence and determinants of placental insufficiency. Predictors of placental dysfunction were ascertained. They included somatic diseases, gestational complications, a positive obstetric and gynecologic history and a series of constitutional factors. Populations of primiparae+- and multigravidae at risk of placental insufficiency were identified.

The paper deals with early prediction of fetal growth retardation and its severity in a newborn from single ultrasound fetal biometric findings (biparietal head size, chest and belly diameters) at week 20 of pregnancy. The prediction was made by employing the developed varying standards for these parameters as percentile curves and tables. A stepwise prediction of fetal growth retardation was proposed for obstetric in- and outpatient settings, which was presented as an IBM personal computer dialogue program. The positive diagnostic value of fetal growth retardation prediction was found to be 69.7%, its negative value was 86.9%. The paper discusses whether therapeutic measures and pregnancy length affect the efficiency of its prediction and stresses that the prediction is valuable for individual well-grounded tactics for pregnancy management.