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According to COI DNA barcoding testing, the marine bivalve mollusc Mactra chinensis, which is native to the Asia-Pacific region, diverged into three species. These species were preliminary characterized as M. chinensis COI clade I, M. chinensis COI clade II and M. chinensis COI clade III. To find out whether it is possible to morphologically distinguish samples representing genetic clades, we examined the color of the shells and the structure of the spermatozoa. It was found that the number of detected coloration types exceeds the number of detected species. In addition, it was shown that individuals belonging to the same genetic clade can have shells of different colors. Consequently, it is impossible to choose one type of shell coloration as a species-specific trait. For sperm, the sperm morphological patterns found in each of the three species are consistent with the M. chinensis sperm model described in previous reports. However, the single sperm variant is also not applicable to discriminate between species derived from M. chinensis, since heterogeneous variants of spermatozoa differing in the length of the acrosomal rod were found. We hypothesized that genetic divergence of species could cause a shift towards predominance of one of the sperm variants, and that species-specific sperm morphs could be quantitatively dominant in molluscs belonging to different clades. However, the dominant sperm morphs were the same in COI clade I and COI clade III. Thus, dominant sperm morphs are useless as species-specific traits. However, shell color and sperm parameters are specific to different geographic regions, and it seems that unique environmental factors can determine shell color and sperm morphology. As a result, both shells and spermatozoa can be used to distinguish the geographical forms of M. chinensis, regardless of the belonging of the forms to a particular genetic clade. Here we propose the introduction of geographic identifiers, in which the shell color and parameters of sperm sets are used as morphological criteria to determine the geographical origin of mollusc specimens belonging to the M. chinensis species complex. [ABSTRACT FROM AUTHOR]

On cruise 82 voyage of the R/V Akademik M.A. Lavrentyev, comprehensive studies of ecosystems associated with hydrothermal vents and cold seeps in the Bering Sea were carried out. New data on the composition and structure of benthic communities of the Piip volcano were obtained. A new area of cold seeps has been discovered on the Chukchi slope of the Bering Sea. At present, the chemosynthesis communities of the Chukchi slope are the northernmost of their kind known in Pacific, and the Chukotka population of Calyptogena is the northernmost Recent population of pliocardiines in the World Ocean. [ABSTRACT FROM AUTHOR]

Mesenchymal stromal cells (MSC) have strong immunomodulatory properties and therefore can be used to control inflammation and tissue damage. It was suggested recently that MSC injections can be used to treat multi-drug resistant tuberculosis (TB). However, MSC trafficking and immunomodulatory effects of MSC injections during Mycobacterium tuberculosis (Mtb) infection have not been studied. To address this issue we have analyzed MSC distribution in tissues and local immunological effects of MSC injections in Mtb infected and uninfected mice. After intravenous injection, MSC accumulated preferentially in the lungs where they were located as cell aggregates in the alveolar walls. Immunological analysis of MSC effects included detection of activated, IFN-γ and IL-4 producing CD4+ lymphocytes, the frequency analysis of dendritic cells (CD11c+F4/80) and macrophages (CD11c-F4/80+) located in the lungs, the expression of IA/IE and CD11b molecules by these cells, and evaluation of 23 cytokines/chemokines in lung lysates. In the lungs of uninfected mice, MSC transfer markedly increased the percentage of IFN-γ+ CD4+ lymphocytes and dendritic cells, elevated levels of IA/IE expression by dendritic cells and macrophages, augmented local production of type 2 cytokines (IL-4, IL-5, IL-10) and chemokines (CCL2, CCL3, CCL4, CCL5, CXCL1), and downregulated type 1 and hematopoietic cytokines (IL-12p70, IFN-γ, IL-3, IL-6, GM-CSF). Compared to uninfected mice, Mtb infected mice had statistically higher “background” frequency of activated CD69+ and IFN-γ+ CD4+ lymphocytes and dendritic cells, and higher levels of cytokines in the lungs. The injections of MSC to Mtb infected mice did not show statistically significant effects on CD4+ lymphocytes, dendritic cells and macrophages, only slightly shifted cytokine profile, and did not change pathogen load or slow down TB progression. Lung section analysis showed that in Mtb infected mice, MSC could not be found in the proximity of the inflammatory foci. Thus, in healthy recipients, MSC administration dramatically changed T-cell function and cytokine/chemokine milieu in the lungs, most likely, due to capillary blockade. But, during Mtb infection, i.e., in the highly-inflammatory conditions, MSC did not affect T-cell function and the level of inflammation. The findings emphasize the importance of the evaluation of MSC effects locally at the site of their predominant post-injection localization and question MSC usefulness as anti-TB treatment. [ABSTRACT FROM AUTHOR]

Benthic communities of the hydrothermally active submarine Piip Volcano (55°445 N, 167°263 E, 368–495 m, the southwestern Bering Sea) were explored during the 75th and 82nd cruises of the RV Akademik M.A. Lavrentyev using the ROV Comanche 18. The Piip Volcano is the northernmost hydrothermal region in the Pacific. Macrofauna composition and community structure were investigated based on qualitative and relative abundance samples along with still images and video records. In total, 130 species of macro- and megafauna were found, of which ∼25% are new to science. Of the fauna, 9 species (7%) are obligate or potentially obligate to environments with access to reduced chemicals. These species are the bivalve Calyptogena pacifica (Vesicomyidae: Pliocardiinae), the gastropods Parvaplustrum wareni (Parvaplustridae) and Provanna sp. (Provannidae), the amphipod Onesimoides sp. (Tryphosidae), the leptostracan Nebalia piipensis (Nebaliidae), the isopod Eurycope andreyi (Munnopsidae), and the polychaetes Neosabellides uschakovi (Ampharetidae), Ophryotrocha beringiana (Dorvilleidae) and Harmothoe globosa (Polynoidae). The total species richness of the Northern and Southern summits was almost identical (90 species and 85 spp respectively), but the number of species on sites without bacterial mats on the Northern Summit (81 spp) was almost 1.5 times higher than on the Southern Summit (57 spp). At the same time the species richness was almost twice higher in habitats with bacterial mats and/or clam beds on the Southern Summit (58 spp) compared to the Northern one (32 spp). The main faunal difference was the absence of Calyptogena pacifica on the Northern Summit. The factors that may explain differences of the faunal communities of the Northern and Southern summits are discussed. The distinctive features of macro- and megafaunal communities of the Piip Volcano were the significant number of taxa, obligate for reducing habitats, of different taxonomic levels including family and subfamily levels and plentiful abundances of sedentary organisms, including the sea anemone Corallimorphus cf. pilatus , the demosponge Vulcanella koltuni , calcareous sponges and benthopelagic Trachimedusa, all of them presumably utilizing the rich food resources of reducing habitats. • 130 mega- and macrofaunal species were found on the hydrothermally active Piip Volcano at 368–495 m depth. • Among 9 species presumably obligate to reducing habitats, 5 were also recorded from seeps outside the volcano. • Numerous sedentary organisms found at bacterial mats, were also known from regular habitats outside the Piip Volcano. • Calyptogena beds were present only on the Southern Summit. • Species richness at bacterial mats and clam beds on the Southern Summit was twice as high as that of the Northern Summit. [ABSTRACT FROM AUTHOR]

• A harmful algal bloom covering ca. 30,000 km2 was observed along the coasts of Kamchatka Peninsula in the fall of 2020. • The Kamchatka bloom caused severe damage to marine life including sea urchins, chitons, octopuses, bivalves, sea anemones, etc. • An assessment of HAB impact on various groups of marine organisms has been carried out for the first time for Russian coastal waters. • The causative organisms of the Kamchatka bloom were identified as Karenia species dominated by Karenia selliformis. • Cells of K. selliformis in the Kamchatka bloom 2020 had rDNA sequences identical to those from Hokkaido in 2021, which belonged to the cold-water group I. In the fall of 2020, a long-lasting and massive harmful algal bloom (HAB) with extensive fields of yellow sea foam was observed in relatively cold waters (7–13 °C) off the coasts of the Kamchatka Peninsula, Russia. According to the estimates based on bio-optical parameters in satellite imagery, the Kamchatka bloom 2020 lasted for two months and covered a vast area of more than 300 × 100 km. An abundance of dead fish and invertebrates, including sea urchins, sea anemones, chitons, cephalopods, bivalves were found on shore during the bloom. Animals suffered almost 100% mortality within a depth range between 5 and 20 m. To identify the causative microalgal species, light and scanning electron microscopy, Raman spectroscopy, and molecular phylogenetic approaches were used. The HAB area was estimated by the spectral analysis of satellite-derived imagery. The causative organisms were unarmored dinoflagellates of Karenia species. Their density and biomass reached 100–620 cells·mL–1 and 1300–7700 mg·m–3, respectively, which accounted for 31–99% of the total cell density and 82–99% of the total phytoplankton biomass in late September to mid-October. The dominant species was Karenia selliformis , and the other co-occurring kareniacean species were K. cf. cristata, K. mikimotoi, K. papilionacea, K. longicanalis , and two unidentified morphotypes of Karenia spp. The molecular phylogeny inferred from LSU rDNA and ITS region showed that K. selliformis from Kamchatka in 2020 belonged to the cold-water group I and was identical to K. selliformis strains from Hokkaido, Japan, identified in 2021. This is the first HAB event caused by K. selliformis recorded from Russian coastal waters. [ABSTRACT FROM AUTHOR]

Methane seep communities on the Koryak slope in the Bering Sea were discovered in 2018 during the 82nd cruise of the RV Akademik M.A. Lavrentyev using ROV Comanche 18. Methane seeps found between 400 m and 695 m depth are the northernmost chemosynthesis-based habitats (∼61°N) known to date in the Pacific. Macrofauna species composition and community structure of methane seep and background benthic communities were investigated at three depth horizons: 400–402 m, 417–429 m and 647–695 m. A total of 335 macrofaunal species were identified. At the depth 647–695 m the species richness in the methane seep communities was 265 species and 72 species in the background. The deepest seep communities were characterized by the highest species richness, relatively high evenness and strong variations in the composition and structure. At shallower depths the species richness was low: 33–34 species at methane seeps and 66–71 in the background. The methane seep communities at shallow depths showed relatively low evenness and low diversity of community structure. The highest species richness at the greatest depth can be related in part to increased habitat heterogeneity associated with carbonate crusts and vesicomyid clam beds occurring only at deeper methane seeps. The deepest methane seep communities were dominated by the chemosymbiotrophic pliocardiine Calyptogena pacifica ; dominant in the background was the ophiuroid Ophiophthalmus normani. At shallower methane seeps only single specimens of C. pacifica were found. The shallower methane seeps were dominated by the background species despite numerous extensive bacterial mats and high potential toxicity of the environment. The seep community at 417–429 m was dominated by the echinoid Brisaster latifrons with population density on the bacterial mat four times higher than in the background. Four chemosymbiotrophic species were recorded at 647–695 m and only one was found at shallower depths. Potentially obligate to reducing habitats polychaetes of the genus Neosabellides and Ophryotrocha occurred in methane seep communities at all depths. Further geochemical, geological and microbiological studies are required to better characterize differences of methane seeps at different depths and reasons of these differences. • Methane seeps were discovered on the Koryak slope (Bering Sea) at 400–700m depth. • Composition and structure of seep communities differed at depths 400–402m, 417–429m and 647–695m. • Background species, echinoids and actiniarians, dominated the shallower seeps. • Chemosymbiotrophic pliocardiine Calyptogena pacifica dominated the deepest seeps. • The deepest seeps have the highest species richness and vary in community structure. [ABSTRACT FROM AUTHOR]

The Russian gastrotrich fauna is virtually unknown, particularly the marine fauna. In the ocean, investigations have been restricted to the White Sea, from where only three fully described species have been reported so far. In this study we describe a new species of Aspidiophorus found in a sandy sample collected from off of Vladivostok (Peter the Great Bay, Sea of Japan). Aspidiophorus oculatus n. sp. is the first marine chaetonotid gastrotrich described from Russia and the first representative of the order Chaetonotida reported from the Sea of Japan. Specimens of the new species are characterized by a body up to 147.5 µm in total length; enveloped by 57 alternating columns of 65-70 keeled, elongate scales. Pharyngeo-intestinal junction at U27; the head bears cephalion, hypostomion, pleuria and a pair of eye-spots; the furca is 20 µm long including the 12-µm long adhesive tube; the ventral interciliary field is naked, with the exception of a pair of elliptical, keeled scales occurring near the anus. Morphological differences between the new species and the other 13 marine con-generic taxa are discussed. A key to the known marine species of the world based on easily identifiable traits, visible in both living and formalin-fixed specimens is provided. [ABSTRACT FROM AUTHOR]

After heart transplantation a number of factors such as pre- and postoperative hypoxia of the myocardium, myocardial failure of the early postoperative period, acute rejection episodes, cytomegalovirus infection, and finally the progressive atherosclerosis of the coronary arteries lead to the development of transplanted heart failure. Severe alterations of the myocardial function at this end stage of the process correspond to incurable cardiomyopathy. The target of plasmapheresis in this case is to decrease the extent of the disturbances in the lipoprotein contents and blood rheology for the improvement of the coronary perfusion of the transplanted heart. Nine patients with 3–7 year survival periods after heart transplantations underwent plasmapheresis twice a year using the Haemonetics PCS-plus machine. 2,100–2,700 ml of plasma was removed. Biochemical data, rheology and coagulation, and the concentration of Sandimmune (Sandoz Pharma Ltd., Basel, Switzerland) were controlled, and radionuclide scintigraphy of the myocardium, coronarographia, and transesophageal ultrasound investigations were completed for these patients. The result was the significant improvement of the coronary perfusion of the myocardium. The level of immunosuppression after the plasmapheresis procedures did not change and therefore did not demand any correction. Thus, we think that plasmapheresis can be an effective method of treatment of posttransplantation cardiomyopathy; the improvement of coronary perfusion decreases the extent of chronic ischemia. Further studies are necessary to answer the question as to whether it is possible to prolong the time before retransplantation with the help of plasmapheresis. [ABSTRACT FROM AUTHOR]

Larvae of priapulids are characterized by radial symmetry evident from both external and internal characters of the introvert and lorica. The bilaterality appears as a result of a combination of several radial symmetries: pentaradial symmetry of the teeth, octaradial symmetry of the primary scalids, 25-radial symmetry of scalids, biradial symmetry of the neck, and biradial and decaradial symmetry of the trunk. Internal radiality is exhibited by musculature and the circumpharyngeal nerve ring. Internal bilaterality is evident from the position of the ventral nerve cord and excretory elements. Externally, the bilaterality is determined by the position of the anal tubulus and two shortened midventral rows of scalids bordering the ventral nerve cord. The lorical elements define the biradial symmetry that is missing in adult priapulids. The radial symmetry of larvae is a secondary appearance considered an evolutionary adaptation to a lifestyle within the three-dimensional environment of the benthic sediment., (Copyright 2001 Wiley-Liss, Inc.)

Priapulids possess a radial symmetry that is remarkably reflected in both external morphology and internal anatomy. It results in the appearance of 25-radial (a number divisible by five) symmetry summarized as a combination of nonaradial, octaradial, and octaradial (9+8+8) symmetries of scalids. The radial symmetry is a secondary appearance considered as an evolutionary adaptation to a lifestyle within the three-dimensional environment of bottom sediment. The eight anteriormost, or primary, scalids retain their particular position because of their innervation directly from the circumpharyngeal brain. As a result of a combination of the octaradial symmetry of primary scalids, pentaradial symmetry of teeth, and the 25-radial symmetry of scalids, the initial bilateral symmetry remains characterized by the single sagittal plane., (Copyright 2001 Wiley-Liss, Inc.)

Background: This study aimed to investigate a possible association between low birth weight (LBW) and other perinatal major characteristics and the risk of a child having accessory pathways of conduction tissue and cardiac arrhythmia later in life., Methods: Thirty-one children aged 1-15 years (12 boys, 19 girls), in whom the persistence of accessory pathways of conduction tissue in the heart and inducible reciprocating supraventricular tachycardia were confirmed by means of programmable transoesophageal pacing, constituted the study group. None of them exhibited signs of either inborn or acquired heart disease causing arrhythmia, and their parents and siblings did not suffer cardiac arrhythmias. The control group was formed of 62 apparently healthy children (two controls for each case) matched to cases for sex, age, date and place of birth. Information on infant perinatal and maternal characteristics was collected retrospectively., Results: High risk of arrhythmia in children was associated with LBW (< 2500 g): odds ratio was equal to 14.6 (95% CI: 1.7-127.9; P = 0.015), and it remained after adjustment had been made for major potential confounders. In addition, children with arrhythmia were more often born with retarded intrauterine growth (birth weight < 10 percentile), preterm (< 37 weeks of gestation), of higher birth order, and had lower Apgar scores at 1 and 5 min. Their mothers more often had diagnosed gynaecological diseases., Conclusions: Antenatal stress leading to LBW may be associated with atypical development and maturation of cardiac conduction system and increased risk of cardiac arrhythmias later in life.

Introverts of Priapulus caudatus and P. tuberculatospinosus bear 25 rows of scalids, as well as 8 spines and scattered papillae in the region the circumoral lip. These, as well as the first ring of pharyngeal teeth in P. tuberculatospinosus, are sensory organs. Although superficially they differ between species, they are all characterized by apical and/or subapical openings which are located on tiny cuticular tubules. All sensory organs contain cilia bearing bipolar receptor cells. The 8 sensory spines situated between the circumoral area and the beginning of the scalids are ultrastructurally similar to the scalids. The introvert and pharyngeal body walls, and associated muscles are described. © 1994 Wiley-Liss, Inc., (Copyright © 1994 Wiley-Liss, Inc.)

The investigations have shown presence of HBsAg in the blood sera of 4% of alcohol abusers and in 17.7% of chronic alcoholics. Among 274 patients with acute viral hepatitis A, more than 50% abuse alcohol. The study has revealed that the lipid spectrum has its specific features in hepatitis patients abusing alcohol and chronically addicted to it. Among patients with chronic persistent hepatitis and cirrhosis of the liver, the combined effects of hepatitis B virus and alcohol have been revealed in 50%.