[Results of studies of human dirofilariasis in Russia].

Human dirofilariasis is a pressing health problem in Russia. By 2014, there have been as many as 850 Dirofilaria repens-infested people living in 42 subjects of the Russian Federation. One of the favorable factors for circulation and spread of invasion is a temperature of above +20-24 degrees C; when the latter is maintained during at least 20 days there may be 1.-1.5 circulations of invasion in the carrier and a 2.8-fold increase in transmission intensity. The border ofa dirofilariasis area with a temperate climate is southward to 58 degrees N in European Russia and West Siberia and southward to 50 degrees N in the Far East. The conditions in the human body have been found to be more favorable for the development of Dirofilaria than considered before and allow the helminth to achieve sexual maturity and to propagate. If man has microfilaremia, he may be a source of invasion. It is necessary to examine venous blood by the enrichment method and, if possible, polymerase chain reaction and enzyme immunoassay, which make it possible to establish a diagnosis in occult invasion and to identify a pathogen species.

[Morphological identification of blastocystis].

The authors have attempted to systematize the currently known specific morphological features of the composition of Blastocystis spp. existing in different forms and to present this material as a reference table, by understanding the need for further data clarification. In addition, the paper describes observations of variations in the forms of human blastocysts. In particular, it depicts the species of multinucleated cysts, the identification of which may cause difficulties in diagnosing and differentiating these forms with some representative species of the genus Entamoeba.

[Pseudoinvasion and transient carriage of the larvae of arthropods and soil nematodes in humans: problems and consequences. The authors' observations and a literature review].

The paper describes cases of pseudoinvasion and transient carriageof the larvae of arthropods and geohelminths. It highlights the objective and subjective factors in the diagnosis of arthropod-borne diseases and geohelminthiasis, which give rise to misdiagnosis. Distinctions between real invasion, transient invasion, and pseudoinvasion are pointed out. The fact that there are special problems with the misdiagnosis of people with mental diseases is emphasized. The key factors for preventing and diagnosing pseudoinvasions and transient carriage are defined.

[Blastocystis spp. culturing as a method for diagnosing the parasite].

The technique for isolating blastocysts in the culture was assessed, by examining the fresh specimens from 196 patients with gastrointestinal tract (GIT) disorders and from 56 persons with an uncertain protozoological diagnosis. A set of techniques, such as triple examination of native smears, parallel inoculation of the Pavlova medium, and microscopy of obtained permanent specimens as may be required, contributes to the timely identification of protozoa, including blastocysts, in persons with GIT disorder. The efficiency of the technique for isolating blastocysts on Pavlova's medium and the native smear test averaged 34.8% and 49.4%, respectively. Among those known to be infected, the rate of parasite development in vitro was not greater than 52.9%. The culture showed amoeboids generally with the clinical manifestation of infection. The culture-based diagnostic method cannot be changed for routine microscopy techniques in detecting blastocysts, although it is essential to investigate the morphofunctional and phylogenetic properties of the parasite. The pleomorphism of cultured blastocysts with variability of growth properties was shown as a manifestation of phenotypic characteristics when isolating the parasite.

[Activity of the anthelmintic agent trichlorophen on the models of human helminthiasis]. / Aktivnost' otechestvennogo antigel'mintika trikhlofena na modeliakh gel'mintozov cheloveka.

Trials of trichlorophen have shown its high efficacy on models of cestode infections: hymenolepiasis (at the adult and cysticercoid stages of development on three types of animals: outbred albino mice, albino rats and golden hamsters), preimaginal echinococciasis alveolaris, larval alveolar echinococciasis (at the early stage of development of the parasite in experiments on cotton rats). The high nematodical activity of trichlorophen was first found on models of trichocephaliasis in DBA/2y mice, nippostrongyloidiasis (in in vitro experiments), and aspiculuriasis in outbred mice. The agent proved to be ineffective at the tissue developmental stage of Hymenolepsis nana (H. nana), the dwarf tapeworm, in albino mice, during experimental opisthorchiasis in golden hamsters. It showed a low efficacy in treating trichinosis in outbred albino mice. Unlike carbamatebenzimidazoles, trichlorophen was inactive at the tissue stage of H. nana; it exerted no effects on the eggs of a dwarf tapeworm in trichinosis. Trichlorophen was also inactive in treating experimental opisthorchiasis in golden hamsters.

[Efficacy of the Russian anthelmintic agent trichlorophen]. / Potentsiruiushchie effecty otechestvennogo antigel'mintika trikhlofena.

Experiments have established the high efficacy of combinations of the micronized dosage form of trichlorophen, with albendazole or medamine in treating trichocephaliasis (its causative agent being Trichocephalus muris) in DBA/2st mice and that of trichlorophen in combination with azinox or fenasal in outbred albino mice with hymenolepiasis (its causative agent being Hymenolepis nana). These combinations are promising in treating patients with cestodosis and nemadosis, respectively.

[The new agent G-1724: synthesis and test on murine models of trichuriasis and trichinosis]. / Sintez i issledovanie novogo preparata G-1724 na modeliakh trikhotsefaleza i trikhinelleza myshei.

To search for new antihelminthics, the new compound N-[3-chloro-4-[(1-ethyl-2-benzimidazolyl) thio]phenyl]-2-hydroxy-3,5-dibromobenzamide (the agent G-1724) was synthesized and tested by using the models of trichocephaliasis (Trichocephalus muris) and trichinosis (Trichinella spiralis). The tests demonstrated that this agent had an nematocidal effect (71-78%).