Biological membrane lipids in norm and pathology (literature review)

This article discusses modern ideas about the structure of biological membranes, presents their basic physicochemical properties, and describes composition and structure of phospholipids from the chemical point of view. Plasmatic membrane has unique receptor-signaling functions regulating essential cellular processes, damage to which can lead to cell death. The article introduces such features of membrane lipids and proteins as fluidity or ability to lateral shift, their permeability and phase conditions; describes the effects of cholesterol on phase transitions, fluidity, elasticity, permeability and mechanical strength of the bilayer. The paper discusses transmembrane or lateral asymmetry of lipid membranes, how it is supported, and what functions it has. Different configurations of hydrocarbon chains of fatty acids and their value are considered. Because the development of various pathological processes and conditions accompanied by molecular biological changes of cell membranes, it primarily concerns erythrocyte membrane, as they are composed of many easily-oxidized phospholipids and they come in contact with relatively high concentrations of oxygen, it is important to examine the role of erythrocyte lipid layer. The impact of various damaging factors on the tissues of cells and organs triggers the universal response as consequence of such molecular mechanisms as intensification of lipid peroxidation, activation of endogenous phospholipases and proteases, reduced activity of antioxidant defense system of the cell

Иксодовые клещи юга Восточной Сибири и Монголии и их спонтанная зараженность возбудителями природно-очаговых трансмиссивных инфекций

The goal of the study is to reveal the species of Ixodid ticks in Eastern Siberia and Mongolia, having epidemiological value and pathogens that transmit to humans via their bites. The tasks is to determine ecologo-epidemiologial characteristics of the main vectors and genetic characteristics of the agents of tick-borne infections. Characterization of the materials. There are materials of the study of more than 200 000 Ixodid ticks of 4 species and their rate of infection by different pathogens with zooparasitological, epidemiological, virological, microbiological, molecular-biological standard and modified to the goals and tasks of the study. Most abundance and dangerous species is Ixodes persulcatus P.Sch. ticks, that is widespread in region investigated. The agents of known vector-borne infections in Eastern Siberia and Mongolia are tick-borne encephalitis virus, Borrelia garinii, Borrelia afze- lii, Rickettsia sibirica, R. sp. DnS14 group.C целью выявления видов иксодовых клещей, имеющих эпидемическое значение на территории Восточной Сибири и Мон- голии, и возбудителей инфекций, передающихся человеку через их укусы, были исследованы эколого-эпидемиологические и ге- нетические характеристики основных переносчиков клещевых инфекций и связанных с ними возбудителей болезней человека. В статье приведены материалы изучения более 200 тыс. экземпляров иксодовых клещей четырех видов, исследован- ных при помощи общепринятых зоопаразитологических, эпидемиологических, вирусологических, микробиологических, молекулярно-биологических и модифицированных применительно к целям и задачам исследования методов. Наиболее массовым и опасным видом является таежный клещ Ixodes persulcatus P. Sch., широко распространенный в регионе. Эпидемиологическое значение имеют также клещи видов Dermacentor nuttalli Ol., Dermacentor silvarum Ol., Hae- maphysalis concinna Koch. Возбудителями трансмиссивных инфекций в Восточной Сибири и Монголии являются вирус КЭ, боррелии, риккетсии, возможно, эрлихии и другие патогены

Review of tapeworms of rodents in the Republic of Buryatia, with emphasis on anoplocephalid cestodes

Examination of ca. 500 rodents [Microtus spp., Myodes spp., Cricetulus barabensis (Pallas), Apodemus peninsulae Thomas] from 14 localities in the Republic of Buryatia (Russian Federation) revealed a minimum of 11 cestode species representing Anoplocephaloides Baer, 1923 s. str. (1 species), Paranoplocephala Lühe, 1910 s. l. (5 species), Catenotaenia Janicki, 1904 (2 species), Arostrilepis Mas-Coma & Tenora, 1997 (at least 2 species) and Rodentolepis Spasskii, 1954 (1 species). At least 5 of these species are previously unknown. The taxonomic and phylogenetic position of Buryatian Paranoplocephala-species was defined by cytochrome oxidase I (COI) sequences (mtDNA). The phylogenetic analysis also confirmed the status of Parandrya Gulyaev & Chechulin, 1996 as a junior synonym of Paranoplocephala s. l.. The species diversity of anoplocephalid cestodes was significantly lower in Buryatia and North-East Siberia (6-7 species) than in Europe (17 species). The connections of the anoplocephalid fauna of Buryatia seem to be closer with Beringia (North-East Siberia and Alaska) than with Europe. The present study demonstrated high spatial variation (patchiness) among study sites in cestodes of Buryatian rodents, with the exception of the ubiquitous Arostrilepis horrida (von Linstow, 1901)-complex