The role of non-commercial cyprinids in maintenance and spread of the opisthorchiasis focus in the middle Ob River basin (Tomsk region, Russia)

The study assessed the role of non-commercial cyprinid species in maintaining the opisthorchiasis focus in the middle Ob River basin, Tomsk region, Russia. The source of O. felineus infection for humans and carnivores is fish of the family Cyprinidae. This is the most numerous family, 14 species live in the middle Ob River basin, which includes 6 commercial species and 8 non-commercial species. This study aimed to investigate the current situation on infestation of non-commercial cyprinids with O. felineus metacercariae and their role in maintaining and spreading the natural focus of opisthorchiasis in the middle Ob River basin. We investigated 4 non-commercial species (tench, sunbleak, common bleak, gudgeon), which are highly abundant in water bodies. Tench, common bleak and gudgeon are objects of amateur fishing. These species are traditionally included in the diet of the local population. Opisthorchis felineus metacercariae were recorded in muscles of all the examined fish species. The identification of metacercariae was confirmed by morphological methods and PCR diagnostics. Tench and sunbleak are the main sources of opisthorchiasis infection in the floodplain lakes of the Ob River basin (the prevalence of tench infection is 89.3% and mean intensity of infection is 11.2 metacercariae per fish, the prevalence of sunbleak infection is 50.9% and the intensity of infection is 4.25 metacercariae per fish). The prevalence of infection in the introduced common bleak from the rivers of the middle Ob River basin is rapidly increasing from 2.4 (2016-2018) to 37.5% (2020-2021), and mean intensity of infection increased from 1 to 4.15. The epizootic state of water bodies in the middle Ob River basin remains unfavorable in relation to opisthorchiasis. Tench, common bleak and sunbleak, along with ide and dace, are the main source of infection for humans and animals, which is evidenced by high infection with Opisthorchis felineus metacercariae in these numerous fish species. They pose the greatest danger of infection of people and animals with opisthorchiasis. These species should be included in the campaign to avoid raw and poorly cooked fish in the diet. In addition, such species as roach, bream and sunbleak also pose the danger of infection with opisthorchiasis, but to a lesser extent

NPRD: Nucleosome Positioning Region Database

Nucleosome Positioning Region Database (NPRD), which is compiling the available experimental data on locations and characteristics of nucleosome formation sites (NFSs), is the first curated NFS-oriented database. The object of the database is a single NFS described in an individual entry. When annotating results of NFS experimental mapping, we pay special attention to several important functional characteristics, such as the relationship between type of gene activity and nucleosome positioning, the influence of non-histone proteins on nucleosome formation, type of the variant of nucleosome positioning (translational or rotational), indication of tissue types and states of cell activity, description of experimental methods used and accuracy of nucleosome position determination, and the results of applying theoretical and computer methods to the analysis of contextual and conformational DNA properties. At present, the NPRD database contains 438 entries and integrates the data described in 124 original papers. The database URL: http://srs6.bionet.nsc.ru/srs6/. Then click the button ‘Databank’ and open the link NUCLEOSOME

Common dace (Leuciscus leuciscus) - A new host of the myxozoan fish parasite, Myxobolus elegans (Cnidaria: Myxozoa) - Short communication

This paper reports the detection of the myxozoan species Myxobolus elegans Kashkovsky 1966 in common dace (Leuciscus leuciscus) that has not been previously listed as its host. The problem of differentiation of phenotypically similar Myxobolus species is addressed. During parasitological survey of common dace from the desalinated part of the Gulf of Finland at the city of Sestroretsk, Russia, numerous oval-shaped plasmodia, 0.2-0.4 mm in size, filled with Myxobolus spores were found on the gills. Pear-shaped myxospores were 15.4 (14.8-16.0) x 10.2 (9.6-10.9) mu m in size with a rib on each valve. On the basis of spore morphology, the species appeared to be similar to M. elegans and Myxobolus hungaricus Jaczo, 1940. In order to identify the species, molecular genetic analysis was performed, and the species was identified on the basis of morphological characteristics and 18S rDNA data. The results obtained indicate that the Myxobolus species observed on the gills of dace is M. elegans. Thus, common dace is another valid host of M. elegans besides the type host, ide (Leuciscus idus)

The morphofunctional and biochemical characteristics of opisthorchiasis-associated cholangiocarcinoma in a Syrian hamster model

The validity of experimental models of pathologies is one of the key challenges in translational medicine. Cholangiocarcinoma, or bile duct cancer, ranks second among oncological diseases of the liver. There is a strong association between bile duct cancer and parasitic infestation of the liver caused by trematodes in the family Opisthorchiidae. We have recently demonstrated that cholangiocarcinoma can develop in Syrian hamsters (Mesocricetus auratus) infected by Opisthorchis felineus and administered with dimethylnitrosamine. However, there is still no description of how this experimental model can possibly be used in translational research. The aim of this work was to study the morphological, functional and biochemical characteristics during cholangiocarcinoma development in Syrian hamsters infected by O. felineus and administered with dimethylnitrosamine. The experi­ment lasted 30 weeks with combined exposure to dimethylnitrosamine in drinking water at a dose of 12.5 ppm and a single injection of 50 metacercariae O. felineus. It was shown that the development of cholangiocarcinoma (18 weeks) increased the total number of basophils, eosinophils and monocytes, the relative number of granulocytes, the amount of total and direct bilirubin, and cholesterol and ALT levels, but reduced the relative number of lymphocytes. Based on pathological, morphometric and biochemical analyses, our model has characteristics similar to those in patients with opisthorchiasisassociated cholangiocarcinoma. Thus, this model can be used to test anticancer drugs, to study the mechanisms of cholangiocarcinogenesis and to search for molecular markers for early diagnosis of bile duct cancer

Experimental opisthorchiasis: a study of blood cells, hematopoiesis and startle reflex in laboratory animals

One of the species of the family Opisthorchiidae, Opisthorchis felineus (O. felineus), causes severe disturbances in humans and animals, and so it is the subject of important research studies. Two weeks after infection we compared the impact of O. felineus invasion on the changes in blood cells composition, bone marrow hematopoiesis and behavioral startlereflex in inbred C57BL/6 male mice and Syrian hamsters (Mesocricetus auratus). Considerable interspecies differences were revealed for many parameters estimated. It was found that the relative weight of the main organ of the peripheral immune system – spleen, is significantly larger in mice than in hamsters. Moreover, the infection with O. felineus caused a significant enlargement of the spleen only in mice. More pronounced changes in the blood cells composition, which was accompanied by activation of hematopoietic stem cells of myeloid and erythroid set, were determined in hamsters. Blood changes in the response to infection in mice were less severe and were not accompanied by the changes in colony formation. Mouse acoustic startle reaction differed from hamster one too. The expression of the startle reaction and the value of pre-pulse inhibition were discriminated in animals of two species. Infected hamsters had no reaction of habituation  to the sound stimulus. In addition, the maturation of O. felineus worms was faster in hamsters than in mice. Data obtained suggest a greater resistance of mice to O. felineus infection, but do not exclude the availability of mice as a model in the study of processes taking place in the host during the development of experimental opisthorchiasis

Антигенные свойства рекомбинантного аналога белка легумаин трематоды Opisthorchis felineus, вызывающей описторхоз у человека

We estimated potential of protein legumain from opisthorchiasis agent O. felineus for application in immunodiagnosis of this disease. Bacterially expressed recombinant protein (rOF49-leg) showed strong difference in Enzyme-linked immunosorbent assay (ELISA) between infected and negative sera. These results suggest the potential of this antigen for development of serodiagnostic test for human opisthorchiasis.Работа посвящена оценке применимости белка легумаин возбудителя описторхоза O. felineusдля иммунодиагностики этого заболевания. Рекомбинантный белок (rOF49-leg), клонированный и экспрессированный в E. coli, в иммуно-ферментном анализе (ИФА) продемонстрировал различие в иммунореактивности между инфицированными и здоровыми сыворотками. Эти результаты показывают потенциальную пригодность этого антигена для разработки серодиагностических тестов на описторхоз

Stegana (Steganina) hypoleuca Meigen 1830

<i>Stegana (Steganina) hypoleuca</i> Meigen, 1830 <p>MATERIAL. 1♀. Altai: Cherny Sugash, Aksas Mt., 14.VII 1964 (N. Violovitch).</p> <p>DISTRIBUTION. Russia: West Siberia [6], European part, Caucasus, East Siberia, Far East. Europe.</p>Published as part of <i>Ivannikov, A. V., Katokhin, A. V. & Sidorenko, V. S., 1998, List Of Droso- Philidae (Diptera) Of West Siberia, pp. 12-16 in Far Eastern Entomologist 57</i> on page 12, DOI: <a href="http://zenodo.org/record/10085027">10.5281/zenodo.10085027</a&gt