Effect of extracts from microalgae on cytokine levels in female C57Bl6 mice

Microalgae from the freshwater basins and seas are a valuable source of broad-spectrum biologically active substances that can affect the cells of immune system and their functional state. Cytokines are involved in all vital processes proceeding in the living cells (proliferation, maturation, differentiation, apoptosis/ necrosis). A study was performed in order to assess the effects of standard food formula for experimental animals supplemented with oil extract of microalgae from various systematic groups upon the levels of cytokines in blood serum, culture media conditioned by immunocytes, as well as kidney and liver tissues. The standard food was impregnated in oil extracts of microalgae (C. vulgaris, Coelastrella sp., A. platensis, C. closterium, and P. purpureum). In control series, the food was impregnated with pure vegetable oil. The animals were fed these foods for 12 days. Blood, spleen and thymus were taken to isolate immunocytes, kidneys and liver, and dimethyl sulfoxide extracts of the cells were produced. The conditioned media of splenocytes and thymocytes were obtained by adding concanavalin A (0 and 10 μg/ml) to the cultured cells. The levels of NO, IL-1β, IL-10, TNFα, and NO were determined in serum, conditioned media, and tissue extracts. In serum, the influence of microalgae on the levels of IL-1β and TNFα was revealed. Activation of immunocytes in experimental groups was followed by changes in IL-1β, TNFα and IL-10 production. Changes of cytokine and NO levels were revealed in liver and kidney extracts in experimental groups. Thus, microalgae extracts of various systematic groups affect the levels of cytokines in blood serum, cultural media conditioned by splenocytes and thymocytes, kidney and liver tissues

Evaluation of age-related distribution of measles cases with primary and secondary immune response in Russian Federation, 2010-2016

In 2010—2016, blood serum samples were examined from 5539 patients, aged < 1—60 years, with clinically and laboratory confirmed measles. Primary or secondary type of immune response was determined for all measles cases. Studies were performed with children aged < 1—14 years (2381), adolescents, 15—17 years old (189), and adults aged 18—60 years (2969). Serum measles-specific IgM antibodies were measured by “VektoKor’ IgM” ELISA test system (Russia), concentration and avidity of specific IgG — by using “Anti-Measles Viruses ELISA/IgG” and “Avidity: Anti-Measles Viruses ELISA/ IgG” (Euroimmun, Germany). Primary immune response was identified based on the presence of serum measles-specific low avidity IgM and IgG antibodies, whereas secondary immune response was characterized by detecting high avidity IgM and IgG antibodies at concentration of ≥ 5.0 IU/ml. Analyzing measles-specific IgM antibodies in 2010—2016 demonstrated that measles morbidity was mainly due to children, aged 1—2 years reaching up to 39.9% of the total number of children with measles aged < 1—14 years as well as adults aged 18—40 years old comprising as high as 80.1% total number of patients aged 15—60 years. Serum measles-specific IgG testing showed that in 15.0% of cases they were detected at concentration of ≥ 5.0 IU/ml. Further serum dilution resulted in finding IgG titer ranging within 8.5—45.0 IU/ml (21.4+0.36) and high avidity antibodies in 80—100% (92.5+0.2) cases. The remaining 85.0% cases found low avidity measles-specific IgG antibodies (< 30%) at concentration of 0.2—3.46 IU/ml (1.73+0.03). An age-related analysis of our data demonstrated that all children under 14 with laboratory-confirmed measles developed primary immune response. Moreover, in 73.7% of measles patients aged 15—60 with primary immune response measles might be prevented by timely vaccination, whereas persons with “vaccine failure” comprised 26.3%. In 2010 (0.09 per 100,000 subjects) and 2016 (0.12 per 100,000 subjects), frequency of patients with “vaccine failure” during relative epidemic well-being was 35.3% and 18.2%, respectively, exceeding 9.9% (p < 0.001) serving as a hallmark 2014 high measles incidence rate (3.24 per 100,000 subjects).The data obtained indicate that measles virus circulate among people with “vaccine failure,” which may account for potential to spread and infect unprotected population cohorts as well as cause measles outbreaks during periods of epidemic well-being

A herd immunity to rubella virus in selected geographical regions

Since 2017, the incidence rate of rubella in the Russian Federation has been below 1 case per million total population. In addition, no circulation of endemic strains of the rubella virus is recorded evidencing about achieving infection elimination phase. In modern conditions, it is important to constantly monitor the level of herd immunity to the rubella virus to identify epidemically significant population groups, especially in countries lacking rubella vaccination or featured with insufficient disease control. Purpose: to study herd immunity to the rubella virus in selected countries in Eurasia and Africa. Materials and methods. Between 2018 and 2021, 15,594 samples of blood sera were tested for IgG and IgM antibodies to the rubella virus from subjects of different ages obtained from regional measles and rubella surveillance centers in the Northwestern Federal District (NWFD) of the Russian Federation, the Republic of Serbia, South Vietnam, and the Republic of Guinea. The “Anti-Rubella Virus ELISA (IgМ)” and “Anti-Rubella Virus ELISA (IgG)” (Euroimmun, Germany) test kits were used. Statistical data processing was carried out using the MS Excel, Prizm 5.0 (GraphPad Software Inc.), and Statistica 8.0 (StatSoft Inc.) software package. Results. During the observation period (2018–2020) the population seroprevalence of the to the rubella virus in the NWFD of the Russian Federation was 96.6–97.7% and fluctuated slightly both in separate years and among individual age groups evidencing about high coverage of rubella vaccination. In the Republic of Serbia conducting two-fold immunization against rubella the overall seroprevalence rate was lower than in the Russian Federation and comprising 86.8%. The minimum number of IgGpositive sera was recorded in the 2–4-year-old age group pointing to the shortcomings of routine vaccination. In South Vietnam, children aged 1–3 years (41.9%) predominated among those recovering from rubella, i.e. the age cohort that should be protected by vaccination at the age of 18 months. No rubella vaccination is carried out in Guinea. The total proportion of seropositive individuals was 75%; herd immunity to the rubella virus was established mainly among children and adolescents, reaching 90% only in the older age group. 30% of unprotected subjects of the most active reproductive age were identified among the females surveyed in Guinea. Conclusion. Insufficient herd immunity to the rubella virus, identified in a number of countries, may contribute to the maintenance of the infectious process and the spread of infection. Globalization contributes to the virus importation into regions being at the stage of measles and rubella elimination. The results obtained suggest about a need to continue efforts aimed at maintaining epidemiological wellbeing regarding rubella in diverse countries of the world.Начиная с 2017 г. в Российской Федерации показатель заболеваемости краснухой находится на уровне ниже 1 случая на 1 млн населения. Также отсутствует циркуляция эндемичных штаммов вируса краснухи. Это свидетельствует о достижении фазы элиминации инфекции. В современных условиях важным является постоянный мониторинг уровня коллективного иммунитета к вирусу краснухи для выявления эпидемически значимых групп населения, особенно в странах, где вакцинация против краснухи не проводится или контроль недостаточен. Цель исследования: изучение коллективного иммунитета к вирусу краснухи в ряде стран Евразии и Африки. Материалы и методы. В период с 2017 по 2021 г. на IgG- и IgM-антитела к вирусу краснухи исследовано 15 594 образца сывороток крови лиц разного возраста, полученные из региональных центров по надзору за корью и краснухой в СЗФО РФ, Республике Сербия, в Южном Вьетнаме, в Гвинейской Республике. Использовали ИФА тест-наборы «Anti-Rubella Virus ELISA IgМ» и «Anti-Rubella Virus ELISA (IgG)» (Euroimmun, Германия). Статистическая обработка результатов проводилась с помощью пакета программ MS Excel, Prizm 5.0 (GraphPadSoftware Inc.), Statistica 8.0 (StatSoft Inc.). Результаты. В СЗФО РФ за период наблюдения серопревалентность населения к вирусу краснухи составляла 96,6–97,7% и колебалась незначительно как по отельным годам, так и среди отдельных возрастных групп, что свидетельствуют о высоком охвате вакцинацией против краснухи. В Республике Сербия общий показатель серопревалентности оказался ниже, чем в РФ, и составил 86,8%. Наименьшее количество IgG-положительных сывороток регистрировали в возрастной группе 2–4 года, что говорит о недостатках плановой вакцинации. В Южном Вьетнаме среди переболевших краснухой преобладали дети в возрасте 1–3 года (41,9%), то есть та группа, которая должна быть максимально защищена плановой прививкой против краснухи в 18 месяцев. В Гвинее специфическая профилактика краснухи не проводится. Общая доля серопозитивных лиц составила 75%, коллективный иммунитет к вирусу краснухи формировался, в основном, среди детей и подростков, достигая 90% лишь в старшей возрастной группе. Среди обследованных женщин Гвинеи выявлено 30% незащищенных лиц наиболее активного репродуктивного возраста. Заключение. Недостаточный уровень коллективного иммунитета к вирусу краснухи, выявленный в ряде стран, может способствовать распространению инфекции, а условия глобализации — импортированию вируса в регионы, находящиеся на этапе элиминации кори и краснухи. Полученные результаты свидетельствуют о необходимости продолжения усилий, направленных на поддержание эпидемиологического благополучия в отношении краснухи в разных странах мира

Корь и краснуха на Северо-Западе России на этапе их элиминации

Aim: To evaluate the epidemic situation on measles and rubella and to carry out the laboratory diagnostics of these infections in the North-West of Russia in the period of elimination.Materials and Methods. In 2016-2019 a total of 534 blood serum samples from patients with measles diagnosis, 210 – from patients with rubella diagnosis and 1251 – from patients with exanthema were studied by ELISA using “VectoMeasles-IgM” and “EIA-Rubella-IgM” test-systems.Results. Measles incidence in NWR varied from 0 to 0.96 per 100,000 in 2016 and 2019, respectively. Among measles patients the proportion of children and adults changed in 2018-2019, adults constituted 65.9%. Patients not vaccinated against measles and those with the unknown vaccination status were mainly involved in epidemic process (85%). High level of patients with revaccination status was revealed in 2018 (18.4%). These patients demonstrated high levels of IgG (>3.0 IU/ml) as well as high percentage of IgG avidity (>94.3%) on 4-7th day of rash onset thus evidencing secondary immune response. Molecular studies of the samples from patients revealed the circulation of D8 and B3 genotypes of measles virus. Strains of D8 and B3 genotypes were represented by 3 and 4 variants, respectively. Rubella incidence did not exceed 0.13 per 100,000. Strains of rubella virus of genotype 1E were detected.Conclusion. The data of annual measles incidence and molecular studies of circulating wild type measles viruses prove the on-going measles elimination process in the NorthWest of Russia. For rubella, the persistent phase of elimination was demonstrated in the region. Цель. Изучение эпидемиологии кори и краснухи на Северо-Западе России на этапе их элиминации.Материалы и методы. В 2016–2019 гг. были исследованы 534 сыворотки крови от больных с диагнозом «Корь», 210 сывороток крови от больных с диагнозом «Краснуха», 1251 сыворотка крови от больных с экзантемными заболеваниями в ИФА c помощью тестсистем «ВектоКорь IgM» и «ИФА-Краснуха-IgM».Результаты. Заболеваемость корью на Северо-Западе России колебалась от 0 в 2017 г. до 0,96 на 100 000 населения в 2019 г. В 2018–2019 гг. изменилось соотношение детей и взрослых среди больных, на долю взрослых приходилось 65,9%. Эпидемический процесс поддерживали непривитые лица и лица с неизвестным анамнезом (85,0%). В 2018 г. отмечен высокий процент больных, имевших ревакцинацию (18,4%). У этой группы больных на 4–7-й дни был выявлен высокий уровень антител класса IgG к вирусу кори (более 3,0 МЕ/мл), а также высокий процент авидности IgG-корь антител (более 94,3%), что свидетельствует о вторичном иммунном ответе. Молекулярно-биологический мониторинг циркуляции диких штаммов вируса кори показал, что на Северо-Западе России в этот период циркулировали вирусы кори двух генотипов: D8 и B3. Штаммы, относящиеся к генотипу D8, были представлены 3 вариантами, к генотипу B3 – 4 вариантами. Заболеваемость краснухой носила спорадический характер и не превышала 0,13 на 100 000 населения. При молекулярно-генетическом исследовании биологического материала были идентифицированы штаммы вируса краснухи генотипа 1Е.Заключение. Данные по ежегодной заболеваемости корью и результаты генотипирования циркулирующих диких штаммов вируса кори свидетельствуют о том, что территории находятся в процессе элиминации кори. В отношении краснухи все показатели подтверждают, что на территориях Северо-Запада России сохраняется устойчивая фаза элиминации краснухи.

Вспышка кори в детской больнице Санкт-Петербурга в 2012 году

Measles was imported to Saint-Petersburg from the Chechen Republic by the patient admitted to the Children’s Clinical Hospital where the measles focus out of 94 cases was formed within the period of January – March, 2012. The typical clinical form of infection was revealed for all measles cases. The general signs of the infection were fever, rash, cough, rhinitis, conjunctivitis. Children under 17 years old consisted three quarters of patients. Among measles patients 75% of cases were the non vaccinated children in the age of 5 months – 14 years. Measles was confirmed by detection of IgM antibodies to measles virus in ELISA in 93.6% of sera samples. Molecular studies of the biological samples from the patient who was the source of the infection as well as from the other patients revealed the measles virus genotype D4 “Iran 2010”. This genotype widely circulated in Iran, Uzbekistan and Kazakhstan as well as in some regions of Russia in 2010–2012. The later diagnostic and isolation of the first measles patient in this hospital facilitated the transmission of measles virus infection in the Hospital where the most part of the non vaccinated children were also treated.В январе–марте 2012 г. в результате заноса кори в детскую городскую больницу пациентом, прибывшим из Чеченской Республики, сформировался очаг кори с 94 случаями заболеваний. У всех больных выявлена типичная клиническая форма кори. Доминирующими симптомами заболевания были высокая температура тела, сыпь, кашель, ринит, конъюнктивит. Среди заболевших в очаге три четверти составили дети в возрасте до 17 лет. Среди больных 75% были непривитые дети от 5 мес. до 14 лет, которые были не вакцинированы либо по возрасту, либо по медицинским показаниям. В сыворотках крови 93,6% больных из очага были обнаружены IgM коревые антитела в ИФА. В биологическом материале от источника инфекции и других больных был выявлен вирус кори генотипа D4 «Иран 2010», который широко циркулировал в 2010–2012 гг. в Иране, Узбекистане, Казахстане и на ряде территорий России. Распространению инфекции способствовали поздняя диагностика и изоляция первого заболевшего корью, пребывание источника инфекции в отделении, где было сосредоточено большое количество детей, не привитых против кори по возрасту и состоянию здоровья, госпитализация больного в инфекционное отделение, не изолированное от других отделений больницы, перемещение больного корью по стационару для получения лечебных процедур

Isostatic Hot Pressed W–Cu Composites with Nanosized Grain Boundaries: Microstructure, Structure and Radiation Shielding Efficiency against Gamma Rays

Abstract: The W–Cu composites with nanosized grain boundaries and high effective density were fabricated using a new fast isostatic hot pressing method. A significantly faster method was proposed for the formation of W–Cu composites in comparison to the traditional ones. The influence of both the high temperature and pressure conditions on the microstructure, structure, chemical composition, and density values were observed. It has been shown that W–Cu samples have a polycrystalline well-packed microstructure. The copper performs the function of a matrix that surrounds the tungsten grains. The W–Cu composites have mixed bcc-W (sp. gr. Im 3 m) and fcc-Cu (sp. gr. Fm 3 m) phases. The W crystallite sizes vary from 107 to 175 nm depending on the sintering conditions. The optimal sintering regimes of the W–Cu composites with the highest density value of 16.37 g/cm3 were determined. Tungsten–copper composites with thicknesses of 0.06–0.27 cm have been fabricated for the radiation protection efficiency investigation against gamma rays. It has been shown that W–Cu samples have a high shielding efficiency from gamma radiation in the 0.276–1.25 MeV range of energies, which makes them excellent candidates as materials for radiation protection. © 2022 by the authorsLicensee MDPI, Basel, Switzerland.Ministry of Education and Science of the Russian Federation, Minobrnauka: 075-15-2020-926Funding: M.V.S. acknowledges financial support from the Ministry of Science and Higher Education of the Russian Federation within the framework of state support for the creation and development of World-Class Research Centers “Digital Biodesign and Personalized Healthcare” No. 075-15-2020-926

TEX264 coordinates p97- and SPRTN-mediated resolution of topoisomerase 1-DNA adducts

Eukaryotic topoisomerase 1 (TOP1) regulates DNA topology to ensure efficient DNA replication and transcription. TOP1 is also a major driver of endogenous genome instability, particularly when its catalytic intermediate—a covalent TOP1-DNA adduct known as a TOP1 cleavage complex (TOP1cc)—is stabilised. TOP1ccs are highly cytotoxic and a failure to resolve them underlies the pathology of neurological disorders but is also exploited in cancer therapy where TOP1ccs are the target of widely used frontline anti-cancer drugs. A critical enzyme for TOP1cc resolution is the tyrosyl-DNA phosphodiesterase (TDP1), which hydrolyses the bond that links a tyrosine in the active site of TOP1 to a 3’ phosphate group on a single-stranded (ss)DNA break. However, TDP1 can only process small peptide fragments from ssDNA ends, raising the question of how the ~90 kDa TOP1 protein is processed upstream of TDP1. Here we find that TEX264 fulfils this role by forming a complex with the p97 ATPase and the SPRTN metalloprotease. We show that TEX264 recognises both unmodified and SUMO1-modifed TOP1 and initiates TOP1cc repair by recruiting p97 and SPRTN. TEX264 localises to the nuclear periphery, associates with DNA replication forks, and counteracts TOP1ccs during DNA replication. Altogether, our study elucidates the existence of a specialised repair complex required for upstream proteolysis of TOP1ccs and their subsequent resolution

Crystal Structure of an Integron Gene Cassette-Associated Protein from Vibrio cholerae Identifies a Cationic Drug-Binding Module

Background The direct isolation of integron gene cassettes from cultivated and environmental microbial sources allows an assessment of the impact of the integron/gene cassette system on the emergence of new phenotypes, such as drug resistance or virulence. A structural approach is being exploited to investigate the modularity and function of novel integron gene cassettes. Methodology/Principal Findings We report the 1.8 A crystal structure of Cass2, an integron-associated protein derived from an environmental V. cholerae. The structure defines a monomeric beta-barrel protein with a fold related to the effector-binding portion of AraC/XylS transcription activators. The closest homologs of Cass2 are multi-drug binding proteins, such as BmrR. Consistent with this, a binding pocket made up of hydrophobic residues and a single glutamate side chain is evident in Cass2, occupied in the crystal form by polyethylene glycol. Fluorescence assays demonstrate that Cass2 is capable of binding cationic drug compounds with submicromolar affinity. The Cass2 module possesses a protein interaction surface proximal to its drug-binding cavity with features homologous to those seen in multi-domain transcriptional regulators. Conclusions/Significance Genetic analysis identifies Cass2 to be representative of a larger family of independent effector-binding proteins associated with lateral gene transfer within Vibrio and closely-related species. We propose that the Cass2 family not only has capacity to form functional transcription regulator complexes, but represents possible evolutionary precursors to multi-domain regulators associated with cationic drug compounds.National Health and Medical Research Council (Australia) (NHMRC grant 488502)National Institutes of Health (U.S.) (Grant GM62414-0 )Ontario. Ministry of Revenue (Challenge Fund

Calcineurin Interacts with PERK and Dephosphorylates Calnexin to Relieve ER Stress in Mammals and Frogs

Background: The accumulation of misfolded proteins within the endoplasmic reticulum (ER) triggers a cellular process known as the Unfolded Protein Response (UPR). One of the earliest responses is the attenuation of protein translation. Little is known about the role that Ca 2+ mobilization plays in the early UPR. Work from our group has shown that cytosolic phosphorylation of calnexin (CLNX) controls Ca 2+ uptake into the ER via the sarco-endoplasmic reticulum Ca 2+-ATPase (SERCA) 2b. Methodology/Principal Findings: Here, we demonstrate that calcineurin (CN), a Ca 2+ dependent phosphatase, associates with the (PKR)-like ER kinase (PERK), and promotes PERK auto-phosphorylation. This association, in turn, increases the phosphorylation level of eukaryotic initiation factor-2 a (eIF2-a) and attenuates protein translation. Data supporting these conclusions were obtained from co-immunoprecipitations, pull-down assays, in-vitro kinase assays, siRNA treatments and [ 35 S]-methionine incorporation measurements. The interaction of CN with PERK was facilitated at elevated cytosolic Ca 2+ concentrations and involved the cytosolic domain of PERK. CN levels were rapidly increased by ER stressors, which could be blocked by siRNA treatments for CN-Aa in cultured astrocytes. Downregulation of CN blocked subsequent ER-stress-induced increases in phosphorylated elF2-a. CN knockdown in Xenopus oocytes predisposed them to induction of apoptosis. We also found that CLNX was dephosphorylated by CN when Ca 2+ increased. These data were obtained from [c 32 P]-CLN