Results of the study of preventive effectiveness and side effects of anti-influenza lactoglobulin in controlled epidemiologic trial]

Prophylactic activity and side action of antiinfluenza lactoglobulin were studied under conditions of controlled epidemiological trial in 6361 persons during the epidemiological rise of influenza incidence. The data obtained pointed to the absence of any protective effect of antiinfluenza lactoglobulin. Marked allergenic properties of lactoglobulin and development of sensitization in the persons under observation were found during the study of the side-effect of the preparation. Thus, the absence of prophylactic efficacy and the sensitizing action of antiinfluenza lactoglobulin pointed to the inexpediency of its use for prophylactic and therapeutic purpose.     

Reactogenicity of a group A and C meningococcal polysaccharide bivalent vaccine

A total of 1 968 persons aged 18-20 years belonging to organized groups were immunized with different doses of polysaccharide meningococcal divaccine, groups A and C, by means of syringes and jet injectors under the conditions of a controlled epidemiological trial. Systemic reactions to the injection of the preparation were found to be absent. Local reactions manifested by inflammation, swelling and tenderness at the site of injection were faintly pronounced and disappeared in 48 hours, which is indicative of low reactogenicity of the preparation under study.     

Catabolism of biphenyl by Pseudomonas putida BS 893 strain containing the biodegradation plasmid pBS241

The isolation and identification of biphenyl catabolism products in Pseudomonas putida BS 893 (pBS241) showed the presence of benzoic, m-hydroxybenzoic and cinnamic acids. The two latter compounds were not found in biphenyl degradation by other bacterial strains. P. putida BS 893 (pBS241) differed from other biphenyl-positive Pseudomonas strains in the enzyme activity. These differences may stem from peculiarities in the pathway of biphenyl catabolism controlled by plasmid pBS241.     

Patterns of clometacillin circulation in the body of laboratory animals]

Distribution of clometacillin in mice, rats and rabbits was studied in comparison with some other penicillins. It was found that clometacillin was superior to all other penicillins used for comparison with respect to the circulation time in the blood after intravenous, intramusclar or intrastomach administration. As for the capacity for penetrating into the tissues from the blood, clometacillin was not inferior to ampicillin and benzylpenicillin and was superior to propicillin, though it was bound by the blood serum proteins to a greater extent than the other penicillins used for comparison.     

Physico-chemical properties of R140G and K141Q mutants of human small heat shock protein HspB1 associated with hereditary peripheral neuropathies

Some physico-chemical properties of R140G and K141Q mutants of human small heat shock protein HspB1 associated with hereditary peripheral neuropathy were analyzed. Mutation K141Q did not affect intrinsic Trp fluorescence and interaction with hydrophobic probe bis-ANS, whereas mutation R140G decreased both intrinsic fluorescence and fluorescence of bis-ANS bound to HspB1. Both mutations decreased thermal stability of HspB1. Mutation R140G increased, whereas mutation K141Q decreased the rate of trypsinolysis of the central part (residues 5–188) of HspB1. Both the wild type HspB1 and its K141Q mutant formed large oligomers with apparent molecular weight ∼560 kDa. The R140G mutant formed two types of oligomers, i.e. large oligomers tending to aggregate and small oligomers with apparent molecular weight ∼70 kDa. The wild type HspB1 formed mixed homooligomers with R140G mutant with apparent molecular weight ∼610 kDa. The R140G mutant was unable to form high molecular weight heterooligomers with HspB6, whereas the K141Q mutant formed two types of heterooligomers with HspB6. In vitro measured chaperone-like activity of the wild type HspB1 was comparable with that of K141Q mutant and was much higher than that of R140G mutant. Mutations of homologous hot-spot Arg (R140G of HspB1 and R120G of αB-crystallin) induced similar changes in the properties of two small heat shock proteins, whereas mutations of two neighboring residues (R140 and K141) induced different changes in the properties of HspB1.     

The ecology of Ixodes trianguliceps ticks and their role in the natural foci of ixodid tick-borne borrelioses in the Middle Urals

From 1994 to 2011, over 7000 individuals of small mammals were captured and examined for ticks in the natural foci of ixodid tick-borne borrelioses (ITBB) in the Middle Urals (Chusovskoy District of Perm Territory). Alongside with the taiga tick (Ixodes persulcatus), which is the main Borrelia vector, approximately 5700 feeding individuals of Ixodes trianguliceps have been identified. The latter species has been found to be about five times less abundant than the former. I. trianguliceps has been collected from small mammals belonging to 19 species. Its main hosts are common shrews (Sorex araneus), bank voles (Clethrionomys glareolus), and northern red-backed voles (C. rutilus). I. trianguliceps shows two seasonal peaks of abundance, spring-summer, and summer-autumn. Plating in BSK II medium yielded 72 isolates of Borrelia from a total of 1142 individuals of I. trianguliceps; 64 isolates have been identified with PCR and RFLP. The mean values of the Borrelia infestation rate in I. trianguliceps larvae, nymphs, and adults are 2.6, 10.2, and 8.1%, respectively, which is 5–10 times lower than in the taiga tick individuals collected from the same mammals. Borreliae obtained from I. trianguliceps (as well as those from I. persulcatus) have been identified as Borrelia garinii and B. afzelii, the former spirochete species being more frequent (about 90% of isolates from I. trianguliceps). Our results indicate that I. trianguliceps ticks participate in circulation of the ITBB causative agents in the forests of the Middle Urals. Rare occurrence of the tick and low rates of its infestation with borreliae suggest that the species is unlikely to play a significant role in the epizootic development in the natural foci of ITBB.     

Structural and functional properties of αβ-heterodimers of tropomyosin with myopathic mutations Q147P and K49del in the β-chain

Tropomyosin (Tpm) is an α-helical coiled-coil actin-binding protein that plays a key role in the Ca²⁺-regulated contraction of striated muscles. Two Tpm isoforms, α (Tpm 1.1) and β (Tpm 2.2), are expressed in fast skeletal muscles. These Tpm isoforms can form either αα and ββ homodimers, or αβ heterodimers. However, only αα-Tpm and αβ-Tpm dimers are usually present in most of fast skeletal muscles, because ββ-homodimers are relatively unstable and cannot exist under physiologic conditions. Nevertheless, the most of previous studies of myopathy-causing mutations in the Tpm β-chains were performed on the ββ-homodimers. In the present work, we applied different methods to investigate the effects of two myopathic mutations in the β-chain, Q147P and K49del (i.e. deletion of Lys49), on structural and functional properties of Tpm αβ-heterodimers and to compare them with the properties of ββ-homodimers carrying these mutations in both β-chains. The results show that the properties of αβ-Tpm heterodimers with these mutations in the β-chain differ significantly from the properties of ββ-homodimers with the same substitutions in both β-chains. This indicates that the αβ-heterodimer is a more appropriate model for studying the effects of myopathic mutations in the β-chain of Tpm than the ββ-homodimer which virtually does not exist in human skeletal muscles.     

Comparative evaluation of the efficacy of Borrelia indication in ixodes ticks (Ixodidae) using dark field microscopy and polymerase chain reaction (PCR)

Indication of Borrelia (B. burgdorferi sensu lato) in 205 adult unfed I. persulcatus ticks from a natural focus was carried out simultaneously by methods of PCR and dark-field microscopy of vital preparations. PCR method revealed Borrelia prevalence in considerable number of ticks, in which Borrelia were not found by microscopy of 250 microscopic fields in a preparation from each individual tick. At the same time, PCR method didn't give positive results for approximately 8% of ticks, which contained rather high concentration of Borrelia (more than 10 per 100 microscopic fields). In general, PCR method doesn't have advantages in comparison with a microscopy of vital preparations for study the Borrelia prevalence in ticks.