Контактная атомно-силовая спектроскопия раковых клеток из эпителия желудка человека

For the first time, we have measured adhesion forces between normal and malignated tissues extracted from human stomach epithelium and the tip of an atomic force microscope. We have found a significant decrease (more than by an order of value) of the adhesion forces of malignated cells, and their contact stiffness, as well.Впервые измерена величина сил адгезии нормальных и раковых клеток из эпителия желудка человека к зонду атомно-силового микроскопа. Обнаружено значительное уменьшение (более чем на порядок величины) силы адгезии малигнизированных клеток и их контактной жёсткости

ПРИРОДНЫЙ РЕЗЕРВУАР ФИЛОВИРУСОВ И ТИПЫ СВЯЗАННЫХ С НИМИ ЭПИДЕМИЧЕСКИХ ВСПЫШЕК НА ТЕРРИТОРИИ АФРИКИ

Family Filoviridae includes a set of etiological agents of human hemorrhagic fevers distributed in Africa: Zaire ebolavirus (ZEBOV), Sudan ebolavirus (SUDV), Bundibugyo ebolavirus (BDBV), Taï Forest ebolavirus (TAFV), Marburg marburgvirus (MMARV). Historiography and recent taxonomical structure of Filoviridae family are considered in the review. The discussed data of laboratory and ecological-virological field researches demonstrate the presence of a natural reservoir of filoviruses among fruit-bats (Chiroptera, Megachiroptera) which carry filovirus infection without clinical signs but allocate viruses with urine, saliva, excrements, and sperm, as well as contain viruses in blood and internals. The potential hosts of filoviruses are various mammal species including the higher primacies (Anthropoidea) and the humans (Homo sapiens sapiens). A brief comparison of anatomic and morphologic features of fruit bats and bats (Chiroptera, Microchiroptera) belonging to another suborder of chiropterans is presented. The description of the basic characteristics of the four types of epidemic outbreaks linked with Filoviridae-associated fevers — speleological (from Ancient Greek σπήλαιον — cave), forest, rural, and urban are given; their possible transformation directions are considered as well.Семейство Filoviridae содержит ряд возбудителей геморрагических лихорадок человека, распространенных на территории Африки: эболавирус Заир (Zaire ebolavirus, ZEBOV), эболавирус Судан (Sudan ebolavirus, SUDV), эболавирус Бундибугё (Bundibugyo ebolavirus, BDBV), (Taï Forest ebolavirus, TAFV), марбургвирус Марбург (Marburg marburgvirus, MMARV). В обзоре представлены историография и рецентная таксономическая структура семейства Filoviridae; выполнен этимологический анализ устаревших и современных названий представителей этого семейства; обсуждаются данные лабораторных и полевых эколого-вирусологических исследований, свидетельствующих о том, что резервуаром филовирусов является подотряд Крыланов (Chiroptera, Megachiroptera), которые переносят филовирусную инфекцию инаппарантно, но выделяют вирусы с мочой, слюной, фекалиями и спермой, а также содержат вирусы в крови и внутренних органах. Потенциальными хозяевами филовирусов является широкий спектр видов млекопитающих, включая высших приматов (Anthropoidea) и человека (Homo sapiens sapiens). В работе приводится краткое сравнение анатомических и морфологических особенностей крыланов и летучих мышей (Chiroptera, Microchiroptera), входящих в другой подотряд отряда Рукокрылых. Дано описание основных характеристик четырех типов эпидемических вспышек филовирусных лихорадок — спелеологического (от др.-греч. σπήλαιον — пещера), лесного, деревенского и городского, а также возможные направления трансформации в процессе их развития и масштабирования

РАЙОНИРОВАНИЕ АФРИКАНСКОЙ ПРИРОДНО-ОЧАГОВОЙ ПРОВИНЦИИ В ОТНОШЕНИИ ФИЛОВИРУСНЫХ ЛИХОРАДОК

The review presents the following division of the African natural foci province into districts: I. Upper Guinea natural focus region includes the following individual natural foci: I.1. Kazamans; I.2. North Guinea; I.3. Volta; I.4. Adamawa; I.5. Sao Tome. II. Central Africa: II.1. Southern Guinea; II.2. Katanga; II.3. Congo; II.4. Azande; II.5. Ruwenzori. III. South-Eastern Africa: III.1. Mafungabusi; III.2. Drakensberg; III.3. Comoros; III.4. Madagascar; III.5. Seychelles; III.6. Mascarenes. For each natural focus the article describes the characteristic landscapes and species list of fruit-bats (Chiroptera, Megachiroptera) which are natural reservoir for viruses belonging to Filoviridae family, the types of epidemic outbreaks and the intensity of filovirus circulation. Possible explanations of narrowness of filoviruses areal in comparison with fruit-bats areal in Africa are discussed.В обзоре предложено районирование африканской природно-очаговой провинции, в составе которой выделены: I. Верхнегвинейский природно-очаговый район, включающий следующие природные очаги: I.1. Казамaнс; I.2. Северо-Гвинейский; I.3. Вόльта; I.4. Адамaва; I.5. Сан-Томe. II. Центральноафриканский: II.1. Южно-Гвинейский; II.2. Катaнга; II.3. Кόнго; II.4. Азaнде; II.5. Рувензόри. III. Юго-Восточноафриканский: III.1. Мафунгабус́ и; III.2. Дракόновы горы; III.3. Комόры; III.4. Мадагаскaр; III.5. Сейшeлы; III.6. Маскарeны.Для каждого природного очага описаны характерные ландшафты, видовой состав крыланов (Chiroptera, Megachiroptera), представляющих собой природный резервуар для вирусов семейства Filoviridae, а также типы эпидемических вспышек и интенсивность циркуляции филовирусов. Обсуждаются возможные объяснения узости ареала филовирусов по сравнению с ареалом крыланов в Африке

Development and Evaluation of a One-Step Quantitative RT-PCR Assay for Detection of Lassa Virus

Lassa fever is a severe viral hemorrhagic illness caused by Lassa virus. Based on estimates, the number of LASV infections ranges from 300,000 to 500,000 cases in endemic areas with a fatality rate of 1%. Development of fast and sensitive tools for the control and prevention of Lassa virus infection as well as for clinical diagnostics of Lassa fever are crucial. Here we reported development and evaluation of a one-step quantitative RT-qPCR assay for the Lassa virus detection – LASV-Fl. This assay is suitable for the detection of lineages I-IV of Lassa virus. The limit of detection of the assay ranged from 103 copies/ml to 105 copies/ml and has 96.4% diagnostic sensitivity, whereas analytical and diagnostic specificities both were 100%. Serum, whole blood and tissue are suitable for use with the assay. The assay contains all the necessary components to perform the analysis, including an armored positive control (ARC+) and an armored internal control (IC). The study was done during the mission of specialized anti-epidemic team of the Russian Federation (SAET) in the Republic of Guinea in 2015-2018. Based on sequencing data, LASV-specific assay was developed using synthetic MS2-phage-based armored RNA particles, RNA from Lassa virus strain Josiah, and further, evaluated in field conditions using samples from patients and Mastomys natalensis rodents. © 2019 Elsevier B.V

Contact atomic force microscopy of biological tissues

The forces of adhesion of the normal and tumor cells of the human stomach epithelium to the probe of an atomic force microscope have been measured for the first time. It is established that the adhesion and contact stiffness of malignant cells are significantly lower than those of the normal cells. © 2010 Pleiades Publishing, Ltd

Contact atomic force microscopy of biological tissues

The forces of adhesion of the normal and tumor cells of the human stomach epithelium to the probe of an atomic force microscope have been measured for the first time. It is established that the adhesion and contact stiffness of malignant cells are significantly lower than those of the normal cells. © 2010 Pleiades Publishing, Ltd

The phylodynamics of the rabies virus in the Russian Federation

Near complete rabies virus N gene sequences (1,110 nt) were determined for 82 isolates obtained from different regions of Russia between 2008 and 2016. These sequences were analyzed together with 108 representative GenBank sequences from 1977-2016 using the Bayesian coalescent approach. The timing of the major evolutionary events was estimated. Most of the isolates represented the steppe rabies virus group C, which was found over a vast geographic region from Central Russia to Mongolia and split into three groups (C0-C2) with discrete geographic prevalence. A single strain of the steppe rabies virus lineage was isolated in the far eastern part of Russia (Primorsky Krai), likely as a result of a recent anthropogenic introduction. For the first time the polar rabies virus group A2, previously reported in Alaska, was described in the northern part of European Russia and at the Franz Josef Land. Phylogenetic analysis suggested that all currently circulating rabies virus groups in the Russian Federation were introduced within the few last centuries, with most of the groups spreading in the 20th century. The dating of evolutionary events was highly concordant with the historical epidemiological data. © 2017 Deviatkin et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

The phylodynamics of the rabies virus in the Russian Federation

Near complete rabies virus N gene sequences (1,110 nt) were determined for 82 isolates obtained from different regions of Russia between 2008 and 2016. These sequences were analyzed together with 108 representative GenBank sequences from 1977-2016 using the Bayesian coalescent approach. The timing of the major evolutionary events was estimated. Most of the isolates represented the steppe rabies virus group C, which was found over a vast geographic region from Central Russia to Mongolia and split into three groups (C0-C2) with discrete geographic prevalence. A single strain of the steppe rabies virus lineage was isolated in the far eastern part of Russia (Primorsky Krai), likely as a result of a recent anthropogenic introduction. For the first time the polar rabies virus group A2, previously reported in Alaska, was described in the northern part of European Russia and at the Franz Josef Land. Phylogenetic analysis suggested that all currently circulating rabies virus groups in the Russian Federation were introduced within the few last centuries, with most of the groups spreading in the 20th century. The dating of evolutionary events was highly concordant with the historical epidemiological data. © 2017 Deviatkin et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Origins of SARS-CoV-2: Window is closing for key scientific studies

Our group was convened by the World Health Organization (WHO) in October 2020. We have been the designated independent international members of a joint WHO–China team tasked with understanding the origins of SARS-CoV-2. Our report was published this March. It was meant to be the first step in a process that has stalled. Here we summarize the scientific process so far, and call for action to fast-track the follow-up scientific work required to identify how COVID-19 emerged, which we set out in this article