[Antigenic and immunogenic activity of virus-like particles based on rabbit hemorrhagic disease virus (Caliciviridae: Lagovirus) genotypes GI1 and GI2 recombinant major capsid proteins].

INTRODUCTION: Rabbit hemorrhagic disease is an acute highly contagious infection associated with two genotypes of pathogenic Lagovirus. Antibodies to major capsid protein (Vp60) are protective. The aim of the work ‒ is an evaluation of antigenic and immunogenic activity of virus-like particles (VLPs) based on recombinant major capsid proteins of both genotypes of rabbit hemorrhagic disease virus (RHDV) (recVP60-GI1 and recVP60-GI2). MATERIALS AND METHODS: Baculovirus-expressed VLPs were evaluated using electron microscopy and administered to clinically healthy 1.53 month old rabbits in a dose of 50 g. Rabbits were challenged with 103 LD50 of virulent strains Voronezhsky-87 and Tula 21 days post immunization. Serum samples were tested for the presence of RHDV-specific antibodies. RESULTS: VLPs with hemagglutination activity forming VLP 3040 nm in size were obtained in Hi-5 cell culture. Specific antibody titers in rabbits measured by ELISA were 1 : 200 to 1 : 800 on 21th day post immunization with VLPs. Immunogenic activity of recVP60-GI1 VLPs was 90 and 40%, while it was 30 and 100% for recVP60-GI2 VLPs after the challenge with RHDV genotypes 1 and 2 respectively. The immunogenicity of two VLPs in mixture reached 100%. DISCUSSION: VLPs possess hemagglutinating, antigenic and immunogenic activity, suggesting their use as components in substances designed for RHDV specific prophylaxis in rabbits. Results of the control challenge experiment demonstrated the need to include the antigens from both RHDV genotypes in the vaccine. CONCLUSION: Recombinant proteins recVP60-GI1 and recVP60-GI2 form VLPs that possess hemagglutinating an antigenic activity, and provide 90100% level of protection for animals challenged with RHDV GI1 and GI2 virulent strains.

[The prevalence of anemia and its associations with other geriatric syndromes in subjects over 65 years old: data of Russian epidemiological study EVKALIPT].

BACKGROUND: A low hemoglobin level in older adults impairs cognitive ability and functional status and associates with risk of falls and fractures, sarcopenia, malnutrition, depression, frailty, and decreased autonomy. Epidemiological data on the anemia prevalence in the geriatric population in our country is not available. AIM: To assess the prevalence of anemia and analyze its associations with geriatric syndromes (GS) in subjects aged 65 years. MATERIALS AND METHODS: 4308 subjects (30% of men) aged 65107 years, living in 11 regions of the Russian Federation, were examined and divided into age groups (6574 years, 7584 years and 85 years). All the participants underwent a comprehensive geriatric assessment and determined hemoglobin level. RESULTS: The anemia prevalence in older adults was 23.9%. It has been shown that with an increase in age per 1 year, the risk of anemia detection increases by 4%. The incidence of anemia was higher in males than females (28.1% versus 22.1%; p0.001). In most cases, anemia was mild. The results of a comprehensive geriatric assessment show that patients with anemia had lower hand grip force, Barthel Index, the sum of points on Lawton instrumental activities of daily living scale, Mini Nutritional Assessment scale, the Mini-Cog test and higher the sum of points on the Geriatric Depression Scale (GDS-15) and the Age Is No Barrier scale. Patients with anemia were more likely to use hearing aids, absorbent underwear, and assistive devices during movement. Patients with anemia had a higher incidence of all GS, except for orthostatic hypotension and chronic pain syndrome. The presence of GS is associated with an increased risk of anemia by 1.33.4 times. CONCLUSION: EVKALIPT study obtained domestic data on the prevalence of anemia in older patients and examined its associations with other GS.

[Healthy life expectancy of people over age 65: results of the Russian epidemiological study EVCALIPT.]

Population health is an important indicator of the general well-being of the population, and it has it's practical significance, as it determines the costs of providing care, social and medical assistance for the elderly. The study presents an assessment of healthy life expectancy indicators of people over age 65 based on the results of the Russian epidemiological study EVCALIPT and a comparison of this results with data from other surveys in Russia and European countries.

[The prevalence of osteoarthritis and its association with geriatric syndromes in people over 65: data from the Russian epidemiological study EVKALIPT].

BACKGROUND: Osteoarthritis (OA) in elderly and senile patients is not only common, but also one of the main diseases affecting the duration of active life, its quality, the appearance of addictions and loss of autonomy. Data on the relationship between OA and geriatric syndromes (GS) in our country are extremely scarce. AIM: To estimate the prevalence of OA and to analyze its associations with HS in persons aged 65 years. MATERIALS AND METHODS: The study included 4308 people (30% of men) aged 65 to 107 years, living in 11 regions of Russia. The patients were divided into 2 groups: with OA (n=2464) and without OA (n=1821). All patients underwent a comprehensive geriatric assessment. RESULTS: The prevalence of OA was 57.6%. With age, the frequency of OA increased significantly. According to the results of a comprehensive geriatric assessment, patients with OA had lower walking speed, the sum of points on the Bartel, Lawton scales and a short battery of physical functioning tests and higher the sum of points on the geriatric scale of depression and the age is not a hindrance scale. Patients with OA rated the quality of life and health status lower and higher the intensity of pain syndrome. Patients with OA were more likely to use any assistive device, with the exception of a wheelchair. In patients with OA, the most common HS were chronic pain syndrome (92%), senile asthenia syndrome (64%), basic (66%) and instrumental (56%) dependence in everyday life, cognitive impairment (62%), probable depression (51%) and urinary incontinence (50%). Univariate regression analysis showed that OA is associated with a 1.23.0-fold increase in the risk of a number of GS and a 28% decrease in the risk of malnutrition. CONCLUSION: OA is widespread in the elderly population. The presence of OA is associated with a number of GS associated with loss of autonomy.

Effect of cationic substitution on the double-well hydrogen-bond potential in [K1-x(NH4)x]3H(SO4)2 proton conductors: a single-crystal neutron diffraction study.

The structure of the mixed crystal [K1-x(NH4)x]3H(SO4)2 as obtained from single-crystal neutron diffraction is compared with the previously reported room-temperature neutron structure of crystalline K3H(SO4)2. The two structures are very similar, as indicated by the high value of their isostructurality index (94.8%). It was found that the replacement of even a small amount (3%) of K+ with NH4+ has a significant influence on the short strong hydrogen bond connecting the two SO42- ions. Earlier optical measurements had revealed that the kinetics of the superionic transition in the solid solution [K1-x(NH4)x]3H(SO4)2 are much faster than in K3H(SO4)2; this reported difference in the kinetics of the superionic phase transition in this class of crystal is explained on the basis of the difference in strength of the hydrogen-bond interactions in the two structures.

Correlates of sequential elements of bimanual behavior in the neuronal activity of the neostriatum in monkeys.

Neuron spike activity was recorded in the putamen of monkeys trained to perform bimanual operant behavior consisting of nine separate steps. Neuronal reactions were present at all steps: in 52-62% of cases during movement, and in 27-36% of cases during responses to the trigger and conditioned signals and as the monkeys decided which was the working hand. The proportion of inhibitory responses to the trigger stimulus was 9%, while inhibitory reactions accounted for 68% of reactions during hand movement in response to the conditioned signal, 33% of reactions when this same hand was used to collect food reinforcement, and 33% of reactions during simultaneous movement of both hands. Reactions significantly differentiating between right- and left-sided tasks were seen at all stages of working-hand decision-taking and in reactions to the signal indicating the correctness of the selection, but were not seen for reactions to the conditioned signal or for activity accompanying movements of one of the animal's hands. These data provide evidence indicating that each step of the complex operant behavior, individual systems of putamen neuronal reactions were created with qualitatively different integral sensitivity to instantaneous behavior.

Collective responses of neostriatal (putamen) neurons during alternative behavior in monkeys.

A monkey (Macaca nemestrina) was trained to perform a behavioral program consisting of the selection and execution of a defined sequence of actions according to a visual conditioned signal. Discriminant analysis was used to evaluate the parameters of the collective activity of six simultaneously recorded putamen neurons. The collective activity of the neurons showed significant differences associated with execution by the monkey of left- and right-sided tasks. These differences were seen to be quite consistent in different groups of neurons. Despite the fact that putamen neurons were involved in the performance of nine separately analyzed fragments of the program, differences were seen in two of these: at the moment of taking the decision relating to the direction of movement, and after its completion when a signal indicating the completed result was presented, independently of whether the animal selected the side for the action correctly or incorrectly. In the case of erroneous decisions, the response mosaic differed from that obtained for correct decisions; however, differences due to previously taken decisions regarding the side of action were preserved. These differences were greater at the point of program completion than at the moment of deciding the direction of movement.

Involvement of striatum (putamen) neurons in motor and nonmotor behavior fragments in monkeys.

Putamen neuron spike activity associated with motor and nonmotor functions was studied in monkeys trained to behavioral programs consisting of a series of sequential actions. In general, each putamen neuron was activated during particular behavior fragments. The association of each individual neostriatal neuron with particular behavioral fragments was not constant. When the animal performed a different version of the same program (using different conditioned signals, right- or left-sided tasks, correct or erroneous performance), the neuron could lose its association with the animal's action and become involved in a different action to which it had previously produced no response. Thus, putamen neurons could demonstrate different functional modalities in different versions of the same actions. The use of additional versions of the given program always led to increases in the numbers of behavior fragments during which there were changes in the spike activity of the neurons of interest. This effect was significantly stronger in motor fragments of the program than in nonmotor fragments. These results show that putamen neurons do not have any defined specialization and have different functional modalities when the animal performs different versions of the same action. The nature of putamen neuron involvement in sensory-cognitive processes was more stable than in the organization of motor responses.

[Reaction of striatal (putamen) neurons on motor and non-motor fragments of behaviour in monkeys]. / Vovlechenie neironov striatuma (skorlupy) v motornye i nemotornye fragmenty povedeniia u obez'ian.

Each putamen neuron responded to several fragments of a behavioural programme, the pattern of such connections being not constant. The response could disappear in a different variant of the behavioural programme while a response to another fragment could occur. Therefore additional variants of the programme were followed by an increase in number of functional modality of a neuron. This was more obvious in motor fragments of the programme. The data obtained suggest that the putamen neurons have no particular specifics, and so involvement of its units in sensory-cognitive processes seem to be more stable than in organisation of movements.

[Collective reactions of neostriatum (putamen) neurons to alternative behaviour in monkeys]. / Kollektivnye reaktsii neironov neostriatuma (skorlupy) vo vremia al'ternativnogo povedeniia obez'iany.

Significant differences were found in collective unit activity of 6 neostriatum neurons associated with performance of either left- or right-sided task by monkeys: at the moment of decision-making regarding the direction of the movement, and after its completion, irrespective of correctness of the choice. The differences at the moment of the programme completion were significantly greater than at the moment of the decision-making.