Computerized methods for therapy and rehabilitation of patients suffering dizziness and balance disorder

A new computerized method is proposed for correction and inhibition of unfavorable illusory (vertigo), vestibular-oculomotor (nystagmus), and vestibular-postural (balance) responses. This method allows to teach the subject to block generalization of an afferent signal to effector mechanisms of the central nervous system by developing a fixational reflex, utilizing a delayed biofeedback. Three variant ofthis method were employed, depending on the kind of stimulation programs aimed at inducing abnormal responses of a certain sensory modality (visual, vestibular or combined). The study involved 36 subjects divided into 3 equal groups one of which had been taught by a visual or vestibular technique, and the last one by a combined. Each group included approximately equal numbers of subjects with vestibulopathies of an organic (peripheral or central) or psychogenic origin. It was demonstrated that the method proposed allows, with the help of computerized stimulation programs, to provoce abnormal illusory and vestibular-optooculomotor responses in the subject, and inhibit them with the help of development of a fixational reflex. Patients were taught using three various variants of the method. A subsequent comparative analysis of results obtained has shown dependence of their effectiveness on the level of disturbance in the vestibular system: the visual variant of correction was the most effective for subjects with peripheral vestibulopathia; for subjects with central vestibulopathia, the vestibular variant was more effective; the combined variant of correction was the most effective for subjects with psychogenic vestibulopathia.     

Prediction of the three-dimensional structure of aflatoxin of Aspergillus flavus by homology modelling

Aflatoxins are polyketide-derived secondary metabolites produced by Aspergillus spp. The toxic effects of aflatoxins have adverse consequences for human health and agricultural economics. The aflR gene, a regulatory gene for aflatoxin biosynthesis, encodes a protein containing a zinc-finger DNA-binding motif. AFLR-Protein three-dimensional model was generated using Robetta server. The modeled AFLR-Protein was further optimization and validation using Rampage. In the simulations, we monitored the backbone atoms and the C-α-helix of the modeled protein. The low RMSD and the simulation time indicate that, as expected, the 3D structural model of AFLR-protein represents a stable folding conformation. This study paves the way for generating computer molecular models for proteins whose crystal structures are not available and which would aid in detailed molecular mechanism of inhibition of aflatoxin.     

Ureaplasma urealyticum and Ureaplasma parvum in etiology of urogenital mixt-infections

The complex study of 104 vaginal samples from patients with urogenital uroplasmosis was carried out. U. parvum were detected in 67.3% patients, U. urealyticum--in 12.5% and in 20.1% cases--two species were registered at the same time. Isolation of clinical significant concentration of both ureaplasma (> 10(4) CFU/ ml) was detected in about 50% of cases. Expression of inflammation of vaginal mucus depended on the level of concentration of infection agents. U. parvum were associated with bacterial vaginosis, while in urogenital candidosis U. parvum was detected rarer than U. urealyticum. The dominant numbers of clinical ureaplasma were high sensitive to "new" macrolides and chinolons, however the high percent of isolates were resistant to erytromicin and doxiciclin.     

Mapping the amino acid properties of constituent nucleoporins onto the yeast nuclear pore complex

Visualization of molecular structures aids in the understanding of structural and functional roles of biological macromolecules. Macromolecular transport between the cell nucleus and cytoplasm is facilitated by the nuclear pore complex (NPC). The ring structure of the NPC is large and contains several distinct proteins (nucleoporins) which function as a selective gate for the passage of certain molecules into and out of the nucleus. In this note we demonstrate the utility of a python code that allows direct mapping of the physiochemical properties of the constituent nucleoporins on the scaffold of the yeast NPC׳s cytoplasmic view. We expect this tool to be useful for researchers to visualize the NPC based on their physiochemical properties and how it alters when specific mutations are introduced in one or more of the nucleoporins. The code developed using Python is available freely from the authors.     

The effect of a long stay under microgravity on the vestibular function and tracking eye movements

Pre-and postflight examinations of cosmonauts participating in missions ISS-3 to ISS-9 on the International Space Station were performed using a computer-aided method of integrated assessment of the oculomotor system. The role and significance of the vestibular system in the eye tracking were determined; the individual and general characteristics of spontaneous oculomotor reactions and oculomotor reactions induced by visual and vestibular stimuli after a long-term stay at zero gravity (126–195 days) were determined; and the changes in the indices of oculomotor reactions were monitored. Studies of the vestibular function, intersensory interactions, and the tracking function of the eyes in the crew members were performed on the second, fifth (sixth), and ninth (tenth) days of the readaptation period. The results of the postflight examinations showed a significant change in the accuracy, velocity, and temporal characteristics of eye tracking and an increase in the vestibular reactivity. It was shown that the structure of visual tracking (the accuracy of fixational eye rotations and smooth tracking) was disturbed (the appearance of correcting saccades, the transition of smooth tracking to saccadic tracking) only in those cosmonauts who, in parallel to an increased reactivity of the vestibular input, also had central changes in the oculomotor system (spontaneous nystagmus, gaze nystagmus). With one exception, recovery of the indices of the accuracy of tracking eye movements in cosmonauts to the background level in the selected period of examination was not observed, although a positive trend was recorded.     

The treatment of isolated genera

Problems presented by genera, or small groups of genera, which have been given family rank are reviewed, and the genera are divided into a number of categories according to the closeness of their affinity to other genera or families. Satellite genera that stand in close relation to families should be united with them. Binary families, that have been divided into two (or more) related families, should be re–united. Families connected by linking genera, should, logically, be united but practical considerations usually prevent this. Clusters of diverse but more or less distantly related genera present unusual problems, being treated either as several, often monogeneric families or as a loosely structured family. Truly isolated genera must be given family and often ordinal rank.     

Effect of otoliths upon function of the semicircular canals after long-term stay under conditions of microgravitation

Results of studies performed in 12 astronauts after flights revealed that in some of them re-adaptation to the Earth gravitation involved increase of spontaneous oculomotor activity in immobile position of the head, suppression of the otolith function in static 40 degrees bending of the head towards right or left shoulders, enhancement of vestibular responsiveness in rotation of the head around the body longitudinal axis at the rate of 0.125 Hz.