Changes in the tissue elements of the gastric mucosa interacting with different strains of Helicobacter pylori, taking into consideration the patient's genotype.

The present study aimed to investigate the peculiarities of adaptation of tissue elements of the gastric mucosa during interaction with Helicobacter pylori, as determined by genetic characteristics of the bacterium and the host. Venous blood and biopsy samples of the mucosa of the antrum and body of the stomach from young patients (18 to 25 years old) were examined. The condition of the gastric mucosa was assessed using stained histological preparations. Venous blood was collected from the patients to ascertain the polymorphisms of the IL-lß and IL-IRN genes. The most pronounced changes were observed in the parameters of reparative regeneration of epithelial differentiation during colonization of the gastric mucosa by H. pylori strains carrying the CagA(+) and BabA2(+) genes. These included an increase in proliferation and apoptosis rates and alterations in epithelial differentiation markers characterized by elevated production of Shh and MUC5AC, as well as a reduction in the production of the protective mucin MUC6 by isthmus gland cells. The presence of the vacAs1 and vacAs2 genes of H. pylori results in a high level of apoptosis in epithelial cells without accelerating proliferation. It was found that after eradication, patients with preserved cellular infiltrates in their gastric mucosa plates were carriers of mainly the IL-1ß*T/IL-1RN*2R haplotypes after 12 months.

Epizootiological aspects of natural nidality of Ixodes tick-borne borreliosis in the Moscow region (Russian Federation).

Background and Aim: At present, tick-borne borreliosis is the most common infectious disease transmitted by ticks in Europe, Asia, and North America. This study aimed to examine the epizootiological aspects of the natural nidality of tick-borne borreliosis in Moscow region (the Russian Federation). Materials and Methods: A total of 2,537 ticks representing two species were collected, namely, Ixodes ricinus and Dermacentor reticulatus. The activity, number of ticks, and Borrelia infestation rates were investigated during a high season, that is, from early spring to mid-autumn. Results: In May, amount of I. ricinus spp. was found 2.5 times more than those representing D. reticulatus spp. (p≤0.01). In June, August, and September, the amount of I. ricinus was 9.0 (p≤0.0001), 2.0 (p≤0.05), and 5.0 times higher, respectively, compared to D. reticulatus. In the first 10 days of April, the amount of D. reticulatus was 3 times higher than that of I. ricinus (p≤0.02); in the next 10 days, their amounts were equal (p≥0.05) and in the last 10 days the amount of I. ricinus exceeded that of D. reticulatus (p≤0.05) by 1.5 times. In general, Borrelia afzelii, and Borrelia garinii, were detected. In addition, the naturally occurring tick-borne borreliosis pesthole was revealed in the Moscow region. Conclusion: Borrelia infection rates for ticks comprise 30%. An increase in Borrelia tick infestation was detected within the vicinity of populated areas. The amount of ticks directly depends on the temperature (20°C-25°C) and moisture (from 50%) values.

Prediction of gene expression regulation by human microRNAs in Plasmodium falciparum.

BACKGROUND: Malaria is a disease annually causing over 400,000 deaths. Deep understanding of molecular and genetic processes underlying its life cycle and pathogenicity is required to efficiently resist it. RNA interference is a mechanism of the gene expression regulation typical for a wide variety of species. Even though the existence of this phenomenon in Plasmodium falciparum has long been rejected, several recent works pose hypotheses and provide direct and indirect evidence of the existence of mechanisms similar to RNA interference in this organism. In particular, the possibility of regulation of P. falciparum gene expression through human microRNAs is of great importance both for fundamental biology and for medicine. In the present work we address the problem of possibility of the existence in the P. falciparum genome of the nucleotide sequences such that mRNAs transcribed from genes containing these sequences could form duplexes with human microRNAs. Using bioinformatics methods we have analysed genomes of 15 P. falciparum isolates for sequences homological to these microRNAs. RESULTS: The analysis has demonstrated the existence of a vast number of genes that could potentially be regulated by the human microRNAs in the plasmodial genome. CONCLUSIONS: Despite the fact that the numbers of homological intervals vary significantly between isolates, the hsa-miR-451a and hsa-miR-223-3p microRNAs are expected to make the most notable contribution to the pathogenesis of P. falciparum malaria. The majority of homological intervals occur in genes encoding cell adhesion proteins.

Effectiveness of doxycycline for the treatment of zoonotic cutaneous leishmaniasis in vivo.

There are available data on in vivo studies of monotherapy of zoonotic cutaneous leishmaniasis with some antibacterial drugs (doxycycline) and their comparison with meglumine antimoniate (glucantime). We used golden Syrian hamsters as a laboratory model. Experimental groups were formed, each of which was treated with one of the tested drugs. Infection of animals was carried out with Leishmania major promastigotes. We selected highly virulent strains of L. major culture isolated from human ulcers or rodents. Meglumine antimoniate monotherapy and doxycycline monotherapy are quite effective and do not differ by the 30th day of their use in such indicators as the average degree of local damage and the average number of Leishmania in the lesions. The main differences were recorded in terms of average body weight gain and average clinical recovery in favour of doxycycline. Leishmania in the lesion on the 60th day were completely absent in treatment with doxycycline. The experiment proved the effectiveness of doxycycline monotherapy: Leishmania in the lesions were absolutely absent by the end of the treatment.