Intestinal microflora in workers of harmful industry

Prolonged work in industry under unhealthy working conditions leads to disturbances in the normal intestinal microflora in employees. The content of bifidobacteria decreases simultaneously with an increase in the amount of opportunistic microorganisms. The degree of disturbances in intestinal microbiocenosis correlates with the length of service.     

Thermodynamic functions of lysozyme, myoglobin, beta-lactoglobulin, albumin, and poly-L-tryptophane in the temperature range 0-330 K

The temperature dependence of heat capacity for lysozyme, myoglobin, beta-lactoglobulin, albumin, and poly-L-tryptophan was studied in the temperature range 5-330 K using an adiabatic vacuum calorimeter. The accuracy of measurements was approximately 0.2%. From the data obtained, the thermodynamic functions of these proteins and the polyamino acid Cp degree (T), H degree (T)-H degree (0), S degree (T)-S degree (0), G degree (T)-H degree (0) in the temperature range 0-330 K, and the values of fractal dimension D and intrinsic temperature theta max were calculated.     

Evolution of asteroarchaediscidae A. Miklukho-Maclay, 1957 in the Carboniferous

This paper discusses the evolution of the family Asteroarchaediscidae, occurring in Eurasia, North America, and North Africa and used in Viséan and Serpukhovian stratigraphy. In particular, the species composition of the euryfacial genus Neoarchaediscus is very important because species of this genus are used for biostratigraphy of the Viséan–Serpukhovian boundary beds and correlation of deep- and shallow-water facies. Members of the family Asteroarchaediscidae are present in the Verkhnyaya Kardailovka Section, a candidate for the global stratotype of the Serpukhovian Stage base.     

Lectin histochemistry for detecting cadmium-induced changes in the glycosylation pattern of rat placenta

Cadmium (Cd) is an industrial and environmental pollutant that produces toxic effects on gametogenesis, pre- and post-implantation embryos, and the placenta. Because the effects of acute Cd intoxication on the placenta are not well understood, we investigated changes in its glycosylated components in Cd treated dams at days 4, 7, 10 and 15 of gestation using lectin histochemistry. CdCl₂ was administered to pregnant rats; control animals received sterile normal saline. Placentas were processed for DBA, Con A, SBA, PNA, UEA-I, RCA-I and WGA lectin histochemistry to evaluate changes in the carbohydrate pattern of the placenta that might modify cell interactions and contribute to embryonic alterations. Lectin binding was analyzed in the yolk sac; trophoblast giant cells; trophoblast I, II and III; spongiotrophoblast cells and endovascular trophoblast cells in the chorioallantoic placenta. Our lectin binding patterns showed that Cd caused alteration of SBA and DBA labeling of trophoblast-derived cells, which suggested increased expressions of α and β GalNAc. Cd also caused decreased UEA-1 binding affinity, which indicated fewer α-L-Fuc residues in placentas of Cd treated dams. The nonreactivity in trophoblast I of the control placentas incubated with Con-A contrasted with the labeling in placentas of experimental dams, which indicated increased expression of terminal α-D-Man, and α-D-Glc residues. We found that Cd altered the reactivity of placenta to several lectins, which indicated modification of the glycotype presented by the fetal component of the placenta. We report that Cd exerts a deleterious effect on the glycosylation pattern of the placenta.     

Nonrandom karyotype changes in chemically induced tumors of the Djungarian hamster

In the cells of tumors induced with methylcholanthrene in wild type and mutant (pink-eyed dilution) Djungarian hamsters non-random involvement in structural changes of certain chromosomes (Xp, 3p and 3q, 7q, 8q) was revealed. In addition, characteristic feature of the majority of tumors was varied number of double-minutes chromosomes (DMs). In some tumors, the markers with long homogeneously or differentially stained regions (HSRs and DSRs) were also present. The DMs, HSRs and DSRs are known as the structures containing amplified genes.     

Dependence of Transformation of Intrinsic Rhythmic Impulse Activity of Neurons on Spatio-Temporal Organization of Synaptic Actions on Dendrites: A Simulation Study

The aim of the study to elucidate the biophysical mechanisms able to determine specific transformations of the patterns of output signals of neurons (neuronal impulse codes) depending on the spatio-temporal organization of synaptic actions coming to the dendrites. We studied mathematical models of the neocortical layer 5 pyramidal neurons built according to the results of computer reconstruction of their dendritic arborizations and experimental data on the voltage-dependent conductivities of their dendritic membrane. This work is a continuation of our previous studies that showed the existence of certain relations between the complexity of neural impulse codes, on the one hand, and the complexity, size, metrical asymmetry of branching, and nonlinear membrane properties of the dendrites, on the other hand. This relation determines synchronous (with some phase shifts) or asynchronous transitions of asymmetrical dendritic subtrees between high and low depolarization states during the generation of output impulse patterns in response to distributed tonic activation of dendritic inputs. In this work we demonstrate the first time that the appearance and pattern of transformations of complex periodical impulse trains at the neuron’s output associated with receiving a short series of presynaptic action potentials are determined not only by the time of arrival of such a series, but also by their spatial addressing to asymmetric dendritic subtrees; the latter, in this case, may be in the same (synchronous transitions) or different (asynchronous transitions) electrical states. Biophysically, this phenomenon is based on a significant excess of the driving potential for a synaptic excitatory current in low-depolarization regions, as compared with that in high-depolarization dendritic regions receiving phasic synaptic stimuli. These findings open a novel aspect of the functioning of neurons and neuronal networks.