Magnetic resonance angiography in the diagnosis of cerebrovascular diseases in systemic lupus erythematosus

Fifty one patients with systemic lupus erythematous were examined using magnetic resonance angiography (MRA) to determine cerebral hemodynamic features. A comprehensive study revealed different cerebral circulatory changes in this abnormality.     

Investigation of erythrocyte shape, plasma membrane fluidity and conformation of haemoglobin haemoporphyrin under the influence of long-term space flight

The investigation of long-term space flight (SF) effect on the blood cells function is of great importance for modern space biology and medicine. We established that the number of discocytes decreased in the period of early rehabilitation after long-term SF. After SF plasma membrane fluidity and phospholipid content decreased and cholesterol content increased. After SF the amount of haemoglobin decreased and the parameters characterizing haemoglobin haemoporyphyrin (HH) conformation changed. We suppose that erythrocyte shape, membrane fluidity and HH conformation are among factors affecting oxygen transfer during and after space flight.     

Isolation and identification of Crimean-Congo hemorrhagic fever virus in the Stavropol territory

The results of the isolation and identification of the causative agent of a haemorrhagic fever outbreak in the Stavropol Territory are presented. The virus isolated from blood of haemorrhagic fever patients by virological methods was identified in serological and molecular tests as Crimean haemorrhagic fever virus. This epidemiological analysis testify to increased activity of the natural focus of Crimean-Congo haemorrhagic fever in this area due to a number of natural and other factors leading to intensification of its epidemic realization.     

Isolation and identification of the smallpox virus which caused iatrogenic vaccinia in children in the city of Vladivostok

The comparative study of the specimens of the morphological elements of exanthema obtained from 8 children with the clinical diagnosis of secondary exogenic vaccinia, dried smallpox vaccine and the cultures of other orthopoxviruses (rabbit pox, monkey pox and buffalo pox viruses) was made. The isolation and identification of the causative agents from the specimens was carried out with the use of modern virological, electron microscopic and molecular methods. The study proved the fact that 8 children had orthopoxvirus infection with its causative agent identified as vaccinia virus.     

Influence of nerve fiber K+ depolarization and altered membrane protein conformation on the state of myelin

Using Raman spectrometry and fluorescence microscopy, we studied the rearrangement of carotenoid molecules and membrane-bound Ca _mb ²⁺ in myelinated nerve fibers after K⁺ depolarization, K⁺-channel blocking, and altering the membrane protein conformation. We observed a decrease in Ca _mb ²⁺ and an increase of microviscosity in myelin after depolarization. Changes in Ca _mb ²⁺ and microviscosity were registered after blocking the K⁺ channels and modifying proteins with PCMB. Our results suggest an interconnection between the condition of nerve fiber membrane proteins, Ca _mb ²⁺ distribution, and myelin microviscosity.     

Orientational Ordering of Carotenoids in Myelin Membranes Resolved by Polarized Raman Microspectroscopy

We study orientational ordering of membrane compounds in the myelinated nerve fiber by means of polarized Raman microspectroscopy. The theory of orientational distribution functions was adapted to live-cell measurements. The obtained orientational distribution functions of carotenoids and lipid acyl chain clearly indicated a predominantly radial-like orientation in membranes of the myelin. Two-dimensional Raman images, made under optimal polarization of incident laser beam, corroborated the proposed carotenoid orientation within the bilayer. Experimental data suggested the tilted orientation of both carotenoid polyenic and lipid acyl chains. The values of maximum tilt angles were similar, with possible implication of carotenoid-induced ordering effect on lipid acyl chains, and hence change of myelin membrane properties. This study stages carotenoids of the nerve as possible mediators of excitation and leverages underlying activity-dependent membrane reordering.     

Seasonal changes in the content of photosynthetic pigments in perennial grasses of cryolithic zone

Seasonal changes in the content of photosynthetic pigments and their ratio were studied in perennial gramineous (Psathyrostachys juncea Tzvel., Elymus sibiricus L., Bromopsis inermis Leys) and equisetaceous (Equisetum variegatum Schleich. ex Web., E. scirpoides Michx.) plants grown under conditions of cryolithic zone in Central and North-East Yakutia (the Pole of Cold). Simultaneously with growth in chlorophyll (Chl) content in all the studied species of perennial grasses of Central Yakutia, a considerable increase in the content of carotenoids (Car) of the xanthophyll cycle (XC) pigments was observed with the beginning of autumn temperature fall. Similar dependence was found in horsetails of the Pole of Cold region: the content of Car was increased by 1.2–3.0 times comparing to the summer values, whereas at the same time the concentration of oxygen-containing forms increased and the ratio of Chl to xanthophylls and Car decreased. In general, horsetails had typically a lower content of Chl and Car, which was determined not only by extremely harsh climatic conditions of the region but also by specific characteristics of Equisetaceae plants. Closer to winter time, the formation of secondary Car, rhodoxanthin, was also observed in the studied horsetail species. In this case, rhodoxanthin presumably plays more important antioxidant role than XC, which can not operate at constantly low temperatures. The obtained data suggest that one of the characteristics of cold hardening of perennial grasses under conditions of cryolithic zone of Yakutia is, presumably, the high level of primary, as well as secondary, Car with most profound antioxidant properties.