Status of the reproductive system of bony fish from the Teterev River and the Kiev Reservoir 20 years after the Chernobyl accident

The status of the reproductive system is investigated in five species of Teleostei from the Teterev River and the Kiev Reservoir (Ukraine), descendants of F₄2–F₇ generations of fish exposed to radiation from the accident at the Chernobyl nuclear power plant. Twenty years after the accident, a wide range of morphofuinctional anomalies of this system is present in fish. The most significant of them are: asymmetry and anomalous morphology of gonads, proliferation of connective tissue—sterilization, mass destruction of follicular and sex cells of various developmental stages, and hermaphroditism. Among the investigated species, disturbances of reproductive glands were preset to the highest extent in pike Esox lucius and crucian carp Carassius carassius. In the series of investigated generations the maximum frequency of occurrence of gonad anomalies was noted in F₄ and F₅, due to prolonged mutagenesis (Dubinin, 1986).     

Analysis of phospholipid molecular species by liquid chromatography--atmospheric pressure chemical ionisation mass spectrometry of diacylglycerol nicotinates.

A method using liquid chromatography - atmospheric pressure chemical ionisation mass spectrometry was evaluated for determining the molecular species composition of phospholipids (phosphatidylcholines from soybean, egg yolk and bovine liver) after conversion to diacylglycerol nicotinate derivatives. The structures could be deduced from pseudo-molecular ions ([MH-123](+)) and three pairs of monoacyl containing fragment ions. All molecular species in mixed peaks were readily identified and many minor components, earlier not encountered in the samples under investigation, were identified. Acyl chain regioisomers were readily distinguished by the ratio of the [MH-RCHCO](+) ions. Molecular species differing only in the position of the double bonds in one polyunsaturated acyl chain were separated on the basis of retention times. A half quantitative estimation of the molecular species composition of complex samples was achieved by a combination of UV detection and, for mixed peaks, the areas of [MH-123](+) ions.     

Determination of the structural integrity of DNA from pathogenic enterobacteria

Among the enterobacterial strains under study, more organisms in the stationary phase of growth have been found to have nicks in their DNA than those in the exponential phase. Bacteria less sensitive to ultraviolet irradiation have the least number of nicks in each phase of growth. The number of nicks in different strains belonging to the serovar is sufficiently stable. Virulent and avirulent forms show no difference in this characteristic.     

Purification of (Ca2+-Mg2+)-ATPase from rat liver plasma membranes

The Ca2+-stimulated, Mg2+-dependent ATPase from rat liver plasma membranes was solubilized using the detergent polyoxyethylene 9 lauryl ether and purified by column chromatography using Polybuffer Exchanger 94, concanavalin A-Sepharose 4B, and Sephadex G-200. The molecular weight of the enzyme, estimated by gel filtration in the presence of the detergent on a Sephadex G-200 column, was 200,000 +/- 15,000. The enzyme was purified at least 300-fold from rat liver plasma membranes and had a specific activity of 19.7 mumol/mg/min. Polyacrylamide gel electrophoresis under nondenaturing conditions of the purified enzyme indicated that the enzymatic activity correlated with the major protein band. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis, one major band in the molecular weight range of 70,000 +/- 5,000 was seen. The isoelectric point of the purified enzyme was 6.9 +/- 0.2 as determined by analytical isoelectric focusing. The enzyme was activated by Ca2+ with an apparent half-saturation constant of 87 +/- 2 nM for Ca2+. Calmodulin and trifluoperazine at the concentration of 1 microgram/ml and 100 microM, respectively, had no effect on the enzymatic activity.     

Reactivity of neurons of the orbito-frontal cortex of the cat during exposure to the scent or sight of food

Reactivity of neurones in orbitofrontal cortex of the cat to the action of light or sound was studied in consecutive stages of alimentary behaviour conditioned by the smell and then the sight of food. Changes were found of the character of neuronal reactions to the light and sound stimuli at the change of smell to the sight of food. A conclusion is drown, that polysensory properties of the neurones of the orbitofrontal cortex provide integral organization of brain sensory function at separate stages of alimentary behaviour.