Semibalanus balanoides (L.) and Balanus crenatus Bruguière (Balanidae) Are Intermediate Hosts of Fimbriarioides intermedia (Fuhrmann, 1913) and Two Species of the Genus Microsomacanthus (Cestoda: Hymenolepidae), Parasites of Sea Ducks from the Atlantic Sector of the Arctic and Northern Pacific.

Metacestode infestation of Semibalanus balanoides (L., 1767) and Balanus crenatus Bruguiеre, 1789, collected in the Barents and White Seas and in the northern part of the Sea of Okhotsk in 2020 and 2021, respectively, was studied. A total of 313 S.

Blocking TGF-β- and Epithelial-to-Mesenchymal Transition (EMT)-mediated activation of vessel-associated mural cells in glioblastoma impacts tumor angiogenesis.

Glioblastoma (GBM) is the most common malignant primary brain tumor in adults. GBM displays excessive and unfunctional vascularization which may, among others, be a reason for its devastating prognosis. Pericytes have been identified as the major component of the irregular vessel structure in GBM.

Two lineages of bivalve transmissible neoplasia affect the blue mussel Gould in the subarctic Sea of Okhotsk.

There are increasing findings of the bivalve transmissible neoplasia derived from the Pacific mussel (BTN) in populations of different species worldwide. The Subarctic is an area where this disease has not yet been sought despite the fact that spp. are widespread there, and itself is a boreal species.

MORPHOLOGY AND ULTRASTRUCTURE OF TWO SCHISTOTAENIID CYSTICERCOIDS (CESTODA: CYCLOPHYLLIDEA) FROM THE HAEMOCOELE OF THE DRAGONFLY LARVAE.

Two cysticercoids, belonging to ascocercus type, namely euascocercus and multicercus, were found in haemocoele of dragonfly larvae of the genus Aeshna from the lakes of the Magadan Province. The cysticercoid of Schistotaenia srivastavai Raush, 1970 (euascocercus) is formed of the outer (exocyst) and inner (endocyst) envelopes, containing the scolex and larval strobila. The outer and inner surfaces of the exocyst are represented by the tegument covered with microvilli.

[On morphogenesis of metacestodes from the family Schistotaeniidae (Cyclophyllidea) by the example of euascocercus Schistotaenia srivastavai Raush, 1970].

Morphogenesis of the true ascocercus (euascocercus or euascocysticercoid) was studied in Schistotaenia srivastavai, a relatively rare parasite of the Red-necked Grebe Podiceps griseigena, and of intermediate hosts, damselfy and dragonfly larvae, in the Okhotsk-Kolyma region. Stages of postembryonic development were reconstructed by the material from spontaneously infected dragonflies' larvae, which corresponded to the published data on the development of metacestodes from the genus Tatria s. l.

Ultrastructural study of protective envelopes in Dioecocestus asper (Cestoda: Dioecocestidae) megalocercus.

The megalocercus of Dioecocestus asper (Mehlis 1831) from the haemocoele of dragonfly larvae possesses two envelopes: outer (exocyst) and inner (endocyst) ones. The exocyst contains the large endocyst and larval strobila with scolex attached to the latter. Outer and inner surfaces of these envelopes are organized as the tegument and have some structural differences.

[On the life cycle and morphology of metacestodes Dioecocestus asper (Cyclophyllidea: Dioecocestidae)].

Metacestodes Dioecocestus asper (Cyclophyllidea) habe been found in larvae of dragonflies Aeshna spp. (Odonata, Anisoptera) from the lakes of the Upper Kolyma and northern Okhotsk seaboard basins (3.8 +/- 0.

Ultrastructure of the cercomer of the metacestode Microsomacanthus paraparvula Regel, 1994 (Cestoda: Hymenolepididae).

Investigations were undertaken using light and transmission electron microscopy to clearly delineate the morphology of the cercomer, i.e. the protective envelopes and tail appendage, in cysticercoids of Microsomacanthus paraparvula, which develop in the haemocoel of the caddisworm Grensia praeterita (Insecta: Trichoptera).

[Microphallus kurilensis sp. nov., a new species of microphallids from the pygmaeus species group (Trematoda, Microphallidae) from the coastal areas of Okhotsk and Bering Seas].

The pygmaeus-species group is composed of close related species from the genus Microphallus in which metacercariae develop inside daughter sporocysts without encystment. Infection of periwinkles Littorina (Neritremna) spp. with intramolluscan stages of a new species of this group (Microphallus kurilensis sp.

[Diagnostic features of Microsomacanthus microsoma (Creplin, 1829), type species of the genus Microsomacanthus Lopez-Neyra, 1942, as the base for the revision of the genus].

The genus Microsomacanthus was created by Lopez-Neyra (1942). Its type species, Taenia microsoma Creplin, 1829, was described from the common eider Somateria mollissima and remained a collective species until Fuhrmann (1913) revealed its diagnostic features on the original material. Simultaneously he described two new species of "microsoma-Gruppe", Microsomacanthus jaegerskioeldi (Fuhrmann, 1913) and M.

[The role of marine amphipods in the life cycles of the cestode genus Microsomacanthus at Bering Sea coast of Chukchi Peninsula. First results of the investigation].

Investigation of the helminth fauna was carried out in different amphipode species at Bering Sea coast of Chukchi Peninsula in July-September 2004. More than 3700 amphipode specimens of the following three species were examined: Lagunogammarus setosus Dementieva, 1931 (n = 2772 specimens) (Gammaridae), Eogammarus barbatus Tzvetkova, 1965 (n = 471), and Spinulogammarus subcarinatus (Bate, 1862) (n = 509) (Anisogammaridae). Numerous metacestodes of four hymenolepidid species from the genus Microsomacanthus Lopez-Neyra, 1945 were found, namely gull parasites M.

Redescription and new data on Microsomacanthus diorchis (Fuhrmann, 1913) (Cestoda: Hymenolepididae).

Microsomacanthus diorchis (Fuhrmann, 1913) is redescribed and illustrated on the basis of the type-material and new findings from common eider Somateria mollissima captured in Iceland and specimens from the same host species from the Barents, White and Bering Seas. A lectotype is designated and an amended diagnosis is provided. The main differentiating features of M.

Redescription and new data on Microsomacanthus jaegerskioeldi (Fuhrmann, 1913) (Cestoda: Hymenolepididae).

Microsomacanthus jaegerskioeldi (Fuhrmann, 1913) is redescribed and illustrated on the basis of type-material from Somateria mollissima captured in the vicinity of Göteborg (Sweden) and specimens from the same host from the Barents Sea, off Iceland and in the East Siberian Sea. A lectotype is designated and an amended diagnosis is provided. Previous reports of this parasite in various hosts and localities are discussed, and the geographical distribution and host range of the species are updated.

[Cestode of the family Hymenolepididae from ducks of Chukotka: Microsomacanthus parasobolevi sp. n.--a widely distributed parasite of eider ducks].

A new species of the genus Microsomacanthus Lopez-Neyra, 1942 is described. The material was collected from eider ducks (Somateria mollissima, S. fischeri, and S.

[About the fauna of the cestode family Hymenolepididae from ducks of Chukotka: on the validity of the genus Echinatrium].

Four species of the genus Echinatrium Spassky et Jurpalova, 1965 are redescribed. The material was collected from ducks of the Chaunskaya lowland (Chukotka). Morphological study of genital apparatus in cestode species found was carried out.

[The cestode fauna of the fam. Hymenolepididae in the anatine birds of Chukotka. The genus Dicranotaenia].

There are 5 species of the genus Dicranotaenia recorded in the North-west of Chukotka: Dicranotaenia coronula (?) (Dujardin, 1845), D. fallax (Krabbe, 1869), D. parvisaccata (Shepard, 1943), D.

[The life cycle and fine morphology of the embryophores in Microsomacanthus paraparvula (Cestoda: Hymenolepididae), a parasite of diving ducks in Chukotka].

It was found out, that the cestode Microsomacanthus paraparvula Regel, 1994 being a common parasite of diving ducks in Chukotka uses a caddisfly Grensia praeteria (Trichoptera) as an intermediate host in its life cycle. Mature fragments of the cestode have been collected from droppings of the experimentally infected nestling of the kittiwake Rissa tridactyla (non-specific host) and used for the fine morphology study of embryonic shells and for an infection of intermediate hosts.

Karyometrical analysis of Microsomacanthus spasskii and M. spiralibursata.

Analysis of Giemsa-stained mitotic metaphase plates of Microsomacanthus spasskii and M. spiralibursata (Cestoda:Hymenolepididae) revealed the diploid chromosome numbers for both species to be 2n = 6. The karyotypes are remarkably similar in general morphology; they both consist of three pairs of metacentric or meta-submetacentric chromosomes graded in size from 4.

[Microsomacanthus paraparvula sp. n. (Cestoda: Hymenolepididae)--a parasite of diving ducks in Chukotka].

Microsomacanthus paraparvula sp. n. differs from all other species of the genus by extremely small length of proglottids and genital organs.

[The physical and technical outlook for neutron therapy in Germany].

All five fast neutron therapy centres in Germany use low energy cyclotrons or neutron generators and are, therefore, at the low energy end of the 21 neutron therapy facilities presently in use worldwide. The depth dose characteristics are worse than for 60Co gamma rays, the absorbed dose rate is too low and the treatment is technically restricted because of the lack of those modern features like multileaf collimators and full gantry rotation that are available with modern linear accelerators. A survey of the statistical and methodical data on the neutron treatment in Germany is presented.

DNA structures and radiation injury.

In the present paper experimental results from radiobiological investigations of the sedimentation behaviour of damaged and restored DNA-subunits attached to the nuclear membrane have been summarized. The studies were carried out preferably with Chinese Hamster cells V79-4 irradiated with different kinds of radiation (gamma-rays, neutrons and carbon ions) using the nucleoid sedimentation technique. Single-strand breaks relax the supercoiled DNA in the subunits resulting in a decreased sedimentation velocity.

[Microsomacanthus polystictae sp. n. and other cestodes of the family Hymenolepididae (Cyclophyllidea) from Steller's eider Polysticta stelleri from the Chaun lowlands (northwestern Chukotka)].

8 species of cestodes belonging to the family Hymenolepididae were recorded from Polysticta stelleri (Pall.) in the Chaun lowland. A new species of hymenolepidids, Microsomacanthus polystictae sp.

Ultrastructural retinal changes after irradiation with fast neutrons.

Morphological changes occurring in the rabbit retina after fast neutron irradiation levels of 250,500 and 1,000 cGy are discussed. The threshold dose that may cause damage to retinal structures is 250 cGy.