Phylogenetic Relationships of the Far Eastern Araliaceae Inferred from ITS Sequences of Nuclear rDNA

In eight species of the family Araliaceae, inhabiting the territory of the Russian Far East, the sequences of ITS regions of nuclear rDNA were determined. A comparison of these sequences enabled establishment of phylogenetic relationships between the Far Eastern and other members of the family. It was demonstrated that Aralia elata populations from Primorye and Sakhalin were genetically different and, hereby, could be classified as intraspecific taxa. Aralia continentalis along with A. cordata were attributed to the section Aralia sensu Wen. Oplopanax elatus and O. horridus were found to be very close to each other, possibly being the subspecies of one species or relatively young species. Legitimacy of the discrimination between two sections within the genus Eleutherococcus was confirmed.__________Translated from Genetika, Vol. 41, No. 6, 2005, pp. 800–810.Original Russian Text Copyright © 2005 by Artyukova, Gontcharov, Kozyrenko, Reunova, Zhuravlev.     

Analysis of Genetic Variation in Rare Endemic Species Oxytropis chankaensis Jurtz. (Fabaceae) Using RAPD Markers

The method of polymerase chain reaction with random primers (RAPD) was used to assess genetic variation and population differentiation in the rare endemic plant Oxytropis chankaensis Jurtz. (Fabaceae). DNA samples from plants of two isolated populations were compared at 133 loci detected by use of ten primers. Both populations examined were characterized by high polymorphism levels (P ₉₅ = 72.9%; A = 1.92 and P ₉₅ = 74.4%; A = 1.88, respectively). They were also statistically significantly different in the frequencies of most of the amplicons. For each of the plants, unique multilocus RAPD phenotype was established using 17 to 20 RAPD markers. Diagnostic markers were not revealed. The populations were poorly differentiated. On average, the between-population component accounted for about 8% of the variation, while 92% of the variation was detected within populations. High variation along with the low degree of differentiation characteristic of two most geographically remote populations of O. chankaensis can have several explanations, among which a polyploid origin of the species seems to be most important.     

Giant multimodal heart motoneurons of Achatina fulica: a new cardioregulatory input in pulmonates.

The regulation of the heartbeat by the two largest neurons, d-VLN and d-RPLN, on the dorsal surface of visceral and right parietal ganglia of Giant African snail, Achatina fulica, was examined. Using the new method of animal preparation, for the first time, discrete biphasic inhibitory-excitatory junction potentials (I-EJPs) in the heart and several muscles of the visceral sac were recorded. The duration of hyperpolarizing phase (H-phase) of biphasic I-EJPs was 269+/-5.6 ms (n=5), which is 2-3 times less than that of the cholinergic inhibitory JPs (682+/-68.5 ms, n=5). The H-phase of I-EJPs was not altered by the application of atropine, picrotoxine, succinylcholinchloride, D-tubocurarine and tetraethylammonium or substitution of Cl(-) ions. Even the low-frequency neuronal discharges (1-2 imp/s) evoked significant facilitation and potentiation of the H-phase. Between the multimodal neurons d-VLN/d-RPLN and mantle or visceral organs there is evidence of direct synaptic connections. These neurons were found to have no axonal branches in the intestinal nerve as once suspected but reach the heart through several other nerves. New giant heart motoneurons do not interact with previously identified cardioregulatory neurons.     

Characteristics of endocrine disorders in the early stages of the development of chronic experimental pancreatitis

The experiments on normal mongrel dogs and those with chronic experimental pancreatitis were performed to reveal the early changes of the endocrine pancreas function. The concentration of immunoreactive insulin and glucagon were studied in afferent vessels of the organ after intraarterial glucose-loading during pancreatic perfusion in situ. The data obtained have shown that in chronic pancreatitis the maximum secretion of insulin is decreased and delayed, as compared to normal animals. At the same time insulin-glucagon secretion ratio remains unchanged. That was indicative of the normal alpha-cell function at the early stages of the disease.     

Quantitative indices of lysozyme activity in staphylococci]

The lysozyme activity of 354 lysozyme-positive and 100 lysozyme-negative (by the results of qualitative test) staphylococcus strains were studied quantitatively. The method was based on titration of the lysozyme in the culture fluid of 48-hour broth cultures of the strains under study. The quantitative method proved to be more sensitive than the qualitative one, and permitted to reveal the lysozyme production in 71% of the strains which were formerly considered to be lysozyme-negative. There were distinct species differences between the lysozyme-positive staphylococci: the mean lysozyme level in the S. aureus was significantly greater then in the S. epidermis. There was no regular association between the lysozyme activity, staphylococcus origin, bacteriophage reference and the antibiotic resistance.     

Absorption by rat fetal tissues of 14C-labeled phospholipids injected into the rat body in the late stages of pregnancy

The authors studied the possibility of 14C-phospholipid transplacental penetration after 15C-phospholipid injection into rats at the 20th day of pregnancy. The preparation of 14C-phospholipids (total phospholipids) was isolated by thin-layer chromatography from the liver of rats injected with 2-14C-sodium acetate. One hour after its injection into the rat, 14C-phospholipids were detectable in total phospholipids of the pulmonary and cerebral fetal tissues. It was discovered that specific radioactivity of phospholipids contained by these tissues was 2--5 times higher when 14C-phospholipids were injected subcutaneously as compared with intramuscular injection. It is concluded that exogenous phospholipids entrapped in the mother's circulation penetrate the placental barrier of the fetus and the blood-brain barrier of the mature fetus, being consumed by different fetal tissues for forming membrane structures of the fetal tissues.     

Respiration and heat production in the embryonic development of chickens

A marked increase in the rate of oxagen consumption and heat production, measured by the direct method, is observed in the chick embryogenesis. The intensity of respiration and heat production of the embryos decreases as the development proceeds. During development the data obtained by direct and indirect calorimetry diverge. This divergence, referred to as psi u-function, gradually decreases by the moment of hatching. Differences in the value of heat production and psi u-function were found in crosses of meat and egg directions, related to differences in the growth rate and productivity of adult fowl.