Lake Baikal amphipods and their genomes, great and small.

Endemic amphipods (Crustacea: Amphipoda) of Lake Baikal represent an outstanding example of large species flocks occupying a wide range of ecological niches and originating from a handful of ancestor species. Their development took place at a restricted territory and is thus open for comprehensive research. Such examples provide unique opportunities for studying behavioral, anatomic, or physiological adaptations in multiple combinations of environmental conditions and thus attract considerable attention. The existing taxonomies of this group list over 350 species and subspecies, which, according to the molecular phylogenetic studies of marker genes, full transcriptomes and mitochondrial genomes, originated from at least two introductions into the lake. The studies of allozymes and marker genes have revealed a significant cryptic diversity in Baikal amphipods, as well as a large variance in genetic diversity within some morphological species. Crossing experiments conducted so far for two morphological species suggest that the differences in the mitochondrial marker (cytochrome c oxidase subunit I gene) can potentially be applied for making predictions about reproductive isolation. For about one-tenth of the Baikal amphipod species, nuclear genome sizes and chromosome numbers are known. While genome sizes vary within one order of magnitude, the karyotypes are relatively stable (2n = 52 for most species studied). Moreover, analysis of the diversity of repeated sequences in nuclear genomes showed significant between-species differences. Studies of mitochondrial genomes revealed some unusual features, such as variation in length and gene order, as well as duplications of tRNA genes, some of which also underwent remolding (change in anticodon specificity due to point mutations). The next important steps should be (i) the assembly of whole genomes for different species of Baikal amphipods, which is at the moment hampered by complicated genome structures with high repeat content, and (ii) updating species taxonomy taking into account all the data.

HspBP1 in Complex with the Peptide of the Innate Immunity Protein Tag7 is Able to Lyse Tumor Cells Carrying TNFR1 Receptor.

The search for new cytotoxic agents capable of lysing tumor cells is an important task in the fight against cancer. Here we have shown that the HspBP1 protein, the chaperone of the heat shock protein Hsp70, is able to form a complex with the previously discovered peptide (17.1) of the innate immunity protein Tag7. Experiments using thermophoresis demonstrated that the affinity of the Tag7 protein peptide 17.1 to the HspBP1 molecule is 100 times higher than that of the full-sized Tag7 molecule. The addition of the 17.1-HspBP1 complex to tumor cells induces apoptosis and necroptosis in them. The results obtained in this work can be used to develop promising antitumor drugs.

Comparison of the evolutionary patterns of DNA repeats in ancient and young invertebrate species flocks of Lake Baikal.

DNA repeat composition of low coverage (0.1-0.5) genomic libraries of four amphipods species endemic to Lake Baikal (East Siberia) and four endemic gastropod species of the fam. Baicaliidae have been compared to each other. In order to do so, a neighbor joining tree was inferred for each quartet of species (amphipods and mollusks) based on the ratio of repeat classes shared in each pair of species. The topology of this tree was compared to the phylogenies inferred for the same species from the concatenated protein-coding mitochondrial nucleotide sequences. In all species analyzed, the fraction of DNA repeats involved circa half of the genome. In relatively more ancient amphipods (most recent common ancestor, MRCA, existed approximately sixty millions years ago), the most abundant were species-specific repeats, while in much younger Baicaliidae (MRCA equal to ca. three millions years) most of the DNA repeats were shared among all four species. If the presence/absence of a repeat is regarded as a separate independent trait, and the ratio of shared to total numbers of repeats in a species pair is used as the measure of distance, the topology of the NJ tree is the same as the quartet phylogeny inferred for the mitogenomes protein coding nucleotide sequences. Meanwhile, in each group of species, a substantial number of repeats were detected pointing to the possibility of non-neutral evolution or a horizontal transfer between species occupying the same biotope. These repeats were shared by non-sister groups while being absent in the sister genomes. On the other hand, in such cases some traits of ecological significance were also shared.

[Isolated splenic lymphangioma]. / Laparoskopicheskaya rezektsiya pri izolirovannoi limfangiome selezenki.

Splenic lymphangioma is a rare malformation of splenic lymphatic channels characterized by cysts resulting from increased number of enlarged thin-walled lymphatic vessels. In our case, there were no clinical manifestations. Lymphangioma was congenital and diagnosed by ultrasound as an accidental finding. Surgery is the only method of radical treatment of splenic lymphangioma. We describe an extremely rare case of pediatric isolated splenic lymphangioma and laparoscopic resection of spleen as the most advantageous variant of surgical treatment.

Incubation of Lymphocytes with IL-2 Causes the Appearance of Antitumor T Cells Carrying FC, CD25, and LFA-1 on the Surface.

To carry out antitumor activity against cells that have lost surface antigens, human lymphocytes must have a certain repertoire of surface proteins capable of contacting a tumor cell and inducing programmed cell death in it. In this work, we showed that activation of healthy donor cells by IL-2 cytokine within 6 days causes the appearance of FasL, CD25, and LFA-1 proteins on CD8+CD25+ T lymphocytes, and also converts the LFA-1 protein into an active form having a high affinity for its target, ICAM-1 integrin. The appearance of these proteins on the surface of this subpopulation of lymphocytes allows them to induce programmed cell death in HLA-negative tumor cells.

Tag7-Mts1 Complex Activates Chemotaxis of Regulatory T Cells.

One of the basic features of immune system is the ability to sustain balance between activation and suppression of effector lymphocytes. In this process a key role belongs to the subpopulation of cells called regulatory T cells (Treg). Many cancer and autoimmune diseases are caused by malfunctions of Treg, and investigation of this subpopulation is important for development of new therapeutic approaches. In this study, we demonstrate that regulatory T cells can migrate along the concentration gradient of Tag7-Mts1 complex, and also they produce agents that induce blood cells migration.

[Comparative evaluation of the effectiveness of narlaprevir in the composition of interferon and interferon-free treatment regimens for patients with chronic hepatitis C].

AIM: Our aim was to give a comparative assessment of the effectiveness of using narlaprevir in combination with pegylated interferon-alpha-2a (Peg-IFN-alpha-2a) and interferon-free mode in patients with chronic hepatitis C (CHC). MATERIALS AND METHODS: The prospective cohort study included 187 patients infected with genotype 1b of hepatitis C virus. Of these, 107 (the 1st group of patients) received narlaprevir 200 mg once a day, ritonavir 100 mg once a day, Peg-IFN-alpha-2a 180 mkg subcutaneously once a week and ribavirin at a dose depending on body weight (10001200 mg per day) for 12 weeks, and then the standart "dual" therapy (Peg-IFN-alpha-2a + ribavirin) was continued until 24 weeks. Patients of the 2nd group (n=80) received antiviral therapy in an interferon-free mode. They received narlaprevir 200 mg once daily, ritonavir 100 mg once daily, and daclatasvir 60 mg once daily for 12 weeks. RESULTS: With the use of an interferon-containing treatment regimen, a sustained virological response was achieved in 92.4% of previousle untreated patients with CH and in 66.7% patients with "unsuccessful" experience of the previous course of treatment. In 5.6% of cases, there was an early termination of treatment due to the development of adverse events. 80 (100%) patients completed the course of treatment with narlaprevir in the interferon-free mode. Sustained virological response was reached by 75 (90%) patients. CONCLUSION: Real clinical practice indicates that the use of narlaprevir in the non-interferon mode is not inferior in efficiency to the interferon-containing treatment regimen and demonstrates a more favorable safety profile.

[MutL Protein from the Neisseria gonorrhoeae Mismatch Repair System: Interaction with ATP and DNA].

The mismatch repair system (MMR) ensures the stability of genetic information during DNA replication in almost all organisms. Mismatch repair is initiated after recognition of a non-canonical nucleotide pair by the MutS protein and the formation of a complex between MutS and MutL. Eukaryotic and most bacterial MutL homologs function as endonucleases that introduce a single-strand break in the daughter strand of the DNA, thus activating the repair process. However, many aspects of the functioning of this protein remain unknown. We studied the ATPase and DNA binding functions of the MutL protein from the pathogenic bacterium Neisseria gonorrhoeae (NgoMutL), which exhibits endonuclease activity. For the first time, the kinetic parameters of ATP hydrolysis by the full-length NgoMutL protein were determined. Its interactions with single- and double-stranded DNA fragments of various lengths were studied. NgoMutL was shown to be able to efficiently form complexes with DNA fragments that are longer than 40 nucleotides. Using modified DNA duplexes harboring a 2-pyridyldisulfide group on linkers of various lengths, we obtained NgoMutL conjugates with DNA for the first time. According to these results, the Cys residues of the wild-type protein are located at a distance of approximately 18-50 Šfrom the duplex. The efficiency of the affinity modification of Cys residues in NgoMutL with reactive DNAs was shown to decrease in the presence of ATP or its non-hydrolyzable analog, as well as ZnCl2, in the reaction mixture. We hypothesize that the conserved Cys residues of the C-terminal domain of NgoMutL, which are responsible for the coordination of metal ions in the active center of the protein, are involved in its interaction with DNA. This information may be useful in reconstruction of the main stages of MMR in prokaryotes that are different from γ-proteobacteria, as well as in the search for new targets for drugs against N. gonorrhoeae.

Cause of death based on systematic post-mortem studies in patients with positive SARS-CoV-2 tissue PCR during the COVID-19 pandemic.

IMPORTANCE: Assessment of the causative association between the COVID-19 and cause of death has been hampered by limited availability of systematically performed autopsies. We aimed to present autopsy-confirmed causes of death in patients who died with COVID-19 and to assess the association between thrombosis and diffuse alveolar damage consistent with COVID-19 (DAD). METHODS: Consecutive forensic (n = 60) and clinical (n = 42) autopsies with positive post-mortem SARS-CoV-2 PCR in lungs (age 73 ± 14 years, 50% men) were included. The cause of death analysis was based on a review of medical records and histological reports. Thrombotic phenomena in lungs were defined as pulmonary thromboembolism (PE), thrombosis in pulmonary artery branches or microangiopathy in capillary vessels. RESULTS: COVID-19 caused or contributed to death in 71% of clinical and 83% of forensic autopsies, in whom significant DAD was observed. Of the patients with COVID-19 as the primary cause of death, only 19% had no thrombotic phenomena in the lungs, as opposed to 38% amongst those with COVID-19 as a contributing cause of death and 54% amongst patients whose death was not related to COVID-19 (p = 0.002). PE was observed in 5 patients. Two patients fulfilled the criteria for lymphocyte myocarditis. CONCLUSIONS: Vast majority of all PCR-positive fatalities, including out-of-hospital deaths, during the SARS-CoV-2 pandemic were related to DAD caused by COVID-19. Pulmonary artery thrombosis and microangiopathy in pulmonary tissue were common and associated with the presence of DAD, whilst venous PE was rarely observed. Histology-confirmed lymphocyte myocarditis was a rare finding.

[Neoplasms of the upper respiratory tract and ear]. / Novoobrazovaniya verkhnikh dykhatel'nykh putei i ukha.

Neoplasms of the upper respiratory tract and ear are tumors of visual localization; however, patients often go to specialized medical institutions in the presence of a widespread tumor process. This paper presents a brief overview of the most common benign and malignant tumors with localization in the oropharynx, nasopharynx, larynx and ear. The clinical picture, diagnosis and various treatment options are presented. Attention is paid to early diagnosis and the need for timely consultation with an oncologist and doctors of related specialties.

[The use of platelet rich plasma in bone-reconstructive in cranio-maxillo-facial surgery]. / Primenenie obogashchennoi trombotsitami plazmy pri kostno-rekonstruktivnykh operatsiyakh v chelyustno-litsevoi khirurgii.

PRP-therapy - method, based on local application platelet rich plasma. Efficiency of this method is investigated and approved both in vitro and in vivo. PRP includes growth factors: platelet derived growth factor, transforming growth factor, epidermal growth factor, insulin-like growth factor, vascular endothelial growth factor, which significantly accelerate regenerative process. PRP-therapy reduces pain syndrome, accelerates tissue regeneration and has an anti-inflammatory effect.

[The Role of Cysteine Residues in the Interaction of Nicking Endonuclease BspD6I with DNA].

Nicking endonucleases (NEs) are a small, poorly studied family of restriction endonucleases. The enzymes recognize a target sequence in DNA, but catalyze the hydrolysis of only one strand. The mechanism of their action is important to study because NEs with new specificities are necessary to design to solve the practical tasks of biotechnology. One of the modern approaches for investigation of protein-nucleic acid interactions is fluorescence spectroscopy, which involves the introduction of fluorophores into proteins, mainly through Cys residues due to the high reactivity of their thiol group. To implement this approach, it is necessary to clarify the role of Cys residues in the functioning of the native protein and the possible consequences of their modification. Crosslinking was used to study whether Cys residues are close to DNA in the complex with NE BspD6I. Reactions were carried out using the wild-type enzyme, its mutant form NE BspD6I(C11S/C160S), and modified DNA duplexes containing the 2-pyridyldisulfide group at the C2' atom of the sugar-phosphate moiety in different positions of the oligonucleotide strand. The Cys residues of NE BspD6I were for the first time shown to be in close proximity to DNA during the binding process, including the step of a nonspecific complex formation. The substitutions C11S and C160S in the N-terminal domain of the enzyme slightly decreased the efficiency of substrate hydrolysis. Construction of a cysteine-free NE BspD6I variant and examination of its properties will provide additional information about the functional significance of the Cys residues for this unique enzyme.

[The functional outcomes of open vertical resections of the larynx]. / Funktsional'nye rezul'taty posle otkrytykh vertikal'nykh rezektsii gortani.

The early diagnostics of the malignant tumours of the larynx provides a basis for the timely beginning of their conservative treatment and endolaryngeal surgical interventions. However, neither the conservative treatment nor endolaryngeal surgery ensures the sufficiently efficient treatment when the tumour spreads over the anterior commissure, subglottic space, and/or laryngeal ventricles. The open surgical resection of the larynx is indicated for the management of the patients presenting with this condition. Our experience is based on the performance of vertical resection of the larynx in 98 patients including the fronto-lateral and extended fronto-lateral interventions in 63 and 35 of them, respectively. The formation of the malignant tumour is known to result in the alteration of the acoustic characteristics of the patient's voice as compared to the initially normal ones in the preceding period. Specifically, the mean values of the fundamental tone frequency increases, the intensity of the sound signal decreases, and the amplitudes of the fundamental tone harmonics tend to be reduced. At the same time, both the dispersion and the variability of the acoustic characteristics being studied undergo an enhancement in comparison with the normal values. Open resection of the larynx with its simultaneous endoscopic correction made it possible to restore the respiratory and vocal functions in 90.8% and 92.1% of the treated patients respectively.

Innate Immune Protein Tag7 Stimulates the Appearance of Cytotoxic NK Cells after Incubation with Lymphocytes.

Tag7 (PGRP-S) is an innate immune protein that is involved in the antibacterial and antitumor defense and stimulates the maturation of cytotoxic lymphocyte subpopulations. It was found that the incubation of lymphocytes with Tag7 for 3 days promotes the appearance of cytotoxic NK cells that are active against a number of tumor cell lines.

Structural uterine changes in postpartum endometritis in cows.

AIM: The purpose of this work was to study the dynamics of structural manifestations of acute cases of postpartum endometritis in cows. MATERIALS AND METHODS: The light and electron microscopy methods were used when studying structural changes in the endometrium in case of postpartum endometritis in seven cows. Sections of endometrial specimens for light microscopy, 5-7 µm thick, were stained with hematoxylin and eosin and also by Van Gieson's. For electron microscopy, semi-thin sections were stained with Azur-2 in combination with basic fuchsin, as well as contrasting by lead citrate and uranyl acetate. RESULTS: As a result of the study, we have established the following: Necrobiosis of the epithelial layer of the mucosa, cellular infiltration with shaped elements of blood in the functional layer, swelling of the cells of the uterine gland, and single microbial cells on the surface of the mucosa. We have noted edema of the stroma of the functional layer of the endometrium, swelling of the epithelial layer of the endometrial mucosa, and swelling of fibroblastic and lymphoid cells. Ultrastructural changes in endometrial cells in case of acute postpartum endometritis in cows are accompanied by the destruction of microvilli on the apical surface of the epithelium, an abundance of coccal microflora on the surface of the epithelium, necrobiosis of epithelial cells, and partial edema of the nucleus, and cytoplasm of the histiocyte. CONCLUSION: We had established that acute purulent-catarrhal dystrophic processes were observed in the structural organization of the endometrium. In the depth of catarrhal mucus on the surface of the endometrium, there was an abundance of bacterial flora, with diplococci being prevalent. In ultrastructural organization of the endometrium, we observed deep dystrophic and necrobiotic processes in the parenchyma and endometrial stroma, as well as exudative processes with a change in the integrity of the microcirculatory bed. Thus, to prevent an inflammatory process from turning into a latent form, it is necessary to detect acute postpartum endometritis promptly using diagnostic methods taking into account the obtained parameters of the dynamics of structural changes in the uterine tissues.

[Adenoid cystic carcinoma of the larynx: a case report]. / Nabliudenie adenokistoznogo raka gortani.

Adenoid cystic carcinoma is one of the rare pathological conditions affecting the larynx. It is known to develop from the glandula elements present in this organ. The authors report a clinical observation of adenoid cystic carcinoma in the form of an exophytic tumour of the pale pink colour having a smooth surface and the well-pronounced vascular patterns at the base. The neoplasm is localized in the arytenoid and retroarytenoid cartilage regions. Being of 3.5-4 cm in size, the tumour causes the narrowing of the larynx in its posterior portions and restricts its mobility. Bearing in mind the considerable extension of the neoplastic process, we undertook laryngectomy including the resection of the orolaryngopharynx and the cervical portion of the oesophagus, the subtotal resection of the thyroid gland and the simultaneous reconstruction of the orolaryngopharynx.

Tag7 (PGLYRP1) Can Induce an Emergence of the CD3+CD4+CD25+CD127+ Cells with Antitumor Activity.

We have shown that in the human peripheral blood cells, the innate immunity protein Tag7 can activate a subpopulation of CD3+CD4+CD25+ cells, which have antitumor activity. These cells can induce lysis of HLA-negative tumor cell lines. The Hsp70 stress molecule on the surface of the tumor cells is used as a recognition target, while the Tag7 protein on the lymphocyte membrane acts as a receptor for Hsp70. We have also demonstrated that this subpopulation of the CD4+CD25+ cells is CD127 positive and hence is not the Treg cells. Our data suggest that this subpopulation of cells is identical to the CD4+CD25+ lymphocytes, which are activated in the leukocyte pool by the IL-2 cytokine.

Tag7-Mts1 Complex Induces Lymphocytes Migration via CCR5 and CXCR3 Receptors.

The discovery of new chemokines that induce the migration of lymphocytes to the infection site is important for the targeted search for therapeutic agents in immunotherapy. We recently showed that Tag7 (PGLYRP1), an innate immunity protein, forms a stable complex with the Ca2+ -binding protein Mts1 (S100A4), which is able to induce lymphocyte movement, although the individual Tag7 and Mts1 do not have this activity. The purpose of this study is to identify receptors that induce the migration of lymphocytes along the concentration gradient of the Tag7-Mts1 complex, and the components of this complex capable of interacting with these receptors. The study investigated the migration of human PBMC under the action of the Tag7-Mts1complex. PBMC of healthy donors were isolated using a standard Ficoll-Hypaque gradient centrifugation procedure. It has been established that the movement of PBMC along the concentration gradient of the Tag7-Mts1 complex is induced by the classical chemotactic receptors CCR5 and CXCR3. It has been shown that only Mts1 is able to bind to the extracellular domain of CCR5, however, this binding is not enough to induce cell movement. A comparative analysis of the primary and 3D structures of the three proteins revealed the homology of the amino acid sequence fragments of the Tag7-Mts1 protein complex with different sites of the CCR5 receptor ligand - MIP1α protein. In conclusion, it should be noted that the Tag7-Mts1 complex can be considered as a new ligand of the classical chemotactic receptors CCR5 and CXCR3.

Effect of Preparation Based on Trametes Pubescens Xylotroph Fungi on Lipid Peroxidation in the Blood of Experimental Animals under Conditions of Dark Stress.

Using the model of dark stress caused by animal maintenance at dimmed light we showed that Trametin (product obtained during liquid-phase culturing of Trametes pubescens xylotroph fungi) effectively prevented oxidative stress under conditions of light deprivation. The preparation increased the level of unsaturation of lipids, reduced the concentration of primary and end-products of LPO, and increases both the integral parameter of the antioxidant defense system (total antioxidant activity) and its components (activity of superoxide dismutase and reduced glutathione).

Lymphocytes incubated in the presence of IL-2 lose the capacity for chemotaxis but acquire antitumor activity.

Naïve non-activated lymphocytes are capable of releasing the chemoattractant complex Tag7-Mts1 and can migrate along the gradient of its concentration. After activation of these cells by IL-2, they acquire the abilities to kill tumor cells and to release the cytotoxic Tag7-Hsp70 complex, which is accompanied by a loss of both the Tag7-Mts1-mediated lymphocyte chemotaxis and the ability to release this chemoattractant into the conditioned medium.