Development, Structure, and Mechanism of Synthetic Antibodies that Target Claudin and Clostridium perfringens Enterotoxin Complexes

Strains of the Gram-positive bacterium Clostridium perfringens produce a two-domain enterotoxin (CpE) that afflict millions of humans and domesticated animals annually by causing prevalent gastrointestinal illnesses. CpEs C-terminal domain (cCpE) binds cell surface receptors then its N-terminal domain restructures to form a membrane-penetrating 𝛽-barrel pore, which is toxic to epithelial cells of the gut. The claudin family of membrane proteins are the receptors for CpE, and also control the architecture and function of cell/cell contacts called tight junctions that create barriers to intercellular transport of solutes. CpE binding disables claudin and tight junction assembly and induces cytotoxicity via 𝛽-pore formation, disrupting gut homeostasis. Here, we aimed to develop probes of claudin/CpE assembly using a phage display library encoding synthetic antigen-binding fragments (sFabs) and discovered two that bound complexes between human claudin-4 and cCpE. We established each sFabs unique modes of molecular recognition, their binding affinities and kinetics, and determined structures for each sFab bound to ~35 kDa claudin-4/cCpE in three-protein comprised complexes using cryogenic electron microscopy (cryoEM). The structures reveal a recognition epitope common to both sFabs but also that each sFab distinctly conforms to bind their antigen, which explain their unique binding equilibria. Mutagenesis of antigen/sFab interfaces observed therein result in further binding changes. Together, these findings validate the structures and uncover the mechanism of targeting claudin-4/cCpE complexes by these sFabs. Based on these structural insights we generate a model for CpEs cytotoxic claudin-bound 𝛽-pore that predicted that these two sFabs would not prevent CpE cytotoxicity, which we verify in vivo with a cell-based assay. This work demonstrates the development and targeting mechanisms of sFabs against claudin/cCpE that enable rapid structural elucidation of these small membrane protein complexes using a cryoEM workflow. It further provides a structure-based framework and therapeutic strategies for utilizing these sFabs as molecular templates to target claudin/CpE assemblies, obstruct CpE cytotoxicity, and treat CpE-linked gastrointestinal diseases that cause substantial economic and quality of life losses throughout the world.

Refugees’ Meaning of Work: A Qualitative Investigation of Work Purposes and Expectations

This study explores the meaning of work for 22 young refugees aged from 18 to 35 from Afghanistan, Eritrea, Iran, Somalia, Syria, Turkey, Ukraine, and Yemen through semistructured interviews. Using consensual qualitative research, we sought to understand the purposes work fulfills, their work expectations, and how purposes and expectations might have changed over time. Results showed that work fulfills many purposes found in the literature, (e.g., development, structure, health, identity, and material benefits) as well as purposes in relation with others and the larger society. Participants expect their work to correspond to their selves (e.g., interests and personality), offer decent working conditions, and allow meaningful relationships and opportunities to help others. Illustrations of two participants’ paths provided insights into a possible change of meaning of work. In addition to implications for practice, the influence of relational and contextual factors is discussed.

Identifying target sites for placental therapeutics through the comparison of normal term pregnancies and intrauterine growth restricted proteomes

A variety of pathologies, including intrauterine growth restriction (IUGR), have been linked to placental insufficiencies as important causal factors, however, little has been done to develop therapeutics that may improve placental development, structure and function. The placenta offers the opportunity to manipulate the in-utero environment without directly intervening with the fetus, accessible from the maternal circulation, a vital but temporary organ, the placenta is no longer required after birth. Developing therapeutics must involve multiple aspects of targeting and safety to ensure no off-target impact on the pregnant person or fetus as well as enhance efficiency of delivery. In addition to our studies on nanoparticle delivery to the placenta [1] we are developing targeting strategies to allow peripheral delivery via the maternal circulation. In this study we have performed the isolation of the microvillous membrane from human placental syncytiotrophoblast (the targeting cell) and via proteomic analysis identified potential targeting moieties, we have then compared this to publicly available data from pregnancies complicated by fetal growth restriction to ensure that we do not identify targets which would be reduced in FGR, resulting in less efficient targeting.

Occupational pathology in the Chukotka and Nenets Autonomous Okrugs: risks, structure, prevalence

Introduction. Labor activity in the Arctic creates an increased risk of developing occupational diseases. In the Chukotka Autonomous Okrug (CHAO), the basis of the economy is the extraction of coal, placer and ore gold, and other non-ferrous metals, and in the Nenets Autonomous Okrug (NAO) - the extraction of oil and natural gas. The study aims to learn the risks of development, structure, and prevalence of occupational pathology among employees of enterprises in the Chukotka and Nenets Autonomous Okrugs. Materials and methods. Scientists studied the results of social and hygienic monitoring under the section "Working conditions and occupational morbidity" in the CHAO and NAO in 2008-2019. Results. In the NAO, almost two-thirds of employees work at facilities with good sanitary and epidemiological well-being indicators, while in the PRAO, only 12%. In the NAO, almost all occupational diseases (96.8%) resulted from exposure to industrial noise (noise effects of the inner ear), mainly in civil aviation pilots. In the CHAO, occupational diseases mainly developed in miners of mining enterprises (80.6%), among which the most common were noise effects of the inner ear (32.5%), chronic bronchitis (24.1%), mono- and polyneuropathies (12.7%). In contrast to the NAO, in 2008-2019, the level of occupational morbidity in the PRAO exceeded all-Russian indicators and tended to increase. The risk of diseases in 2017-2019 was higher than in 2008-2010: RR=2.51; CI 1.62-3.89, p<0.001. In 2008-2019 the probability of the formation of occupational pathology among employees of enterprises in the CHAO was higher than in the NAO: RR=3.84; CI 2.92-5.06, p<0.001. Conclusion. To reduce the occupational morbidity of miners of the CHAO, it is necessary to improve personal protective equipment and technological equipment to reduce noise levels, vibration, the concentration of aerosols of predominantly fibrogenic action, and the severity of the labor process. The use of aviation headsets with an increased level of noise reduction will help reduce the exposure of workers to noise. For solving this problem, it is necessary to update the flight fleet of civil aviation in NAO.

European practices for the development of PhD training courses (on the example of personal development course)

В статье представлены результаты применения европейских практик разработки учебных курсов на примере курса личностного развития для аспирантов российских и белорусских университетов. Авторы курса входят в команду международного консорциума вузов по реализации программы Erasmus+ проект MODEST (Modernization of Doctoral Education in Science and Improvement Teaching Methodologies – Модернизация обучения в аспирантуре по естественным наукам и улучшение педагогических методик). Цель разработанного курса: развитие эмоционального интеллекта, а также и эффективных навыков стресс-менеджмента и управления временем. Методологическими основами разработки курса явились теория результатов обучения Д.Кеннеди и концепция развития гибких навыков. Разработанная структура, содержание и технология курса проходят апробацию в процессе подготовки аспирантов и молодых исследователей в университетах России и Беларуси. Внедрение курса будет реализованов практике деятельности Doctoral Training Centers – Тренинговых центров для аспирантов, организованных на базе университетов консорциума проекта MODEST программы ERASMUS+ в странах: Россия; Беларусь и Армения. Article presents results of training course design according to European practices by example of a Personal Development course for PhD students of Russian and Belarusian universities. Authors are part of an international consortium of universities team of the Erasmus + MODEST project implementation (Modernization of Doctoral Education in Science and Improvement Teaching Methodologies). Course goal: development of emotional intelligence, as well as effective stress management and time management skills. Methodological foundations of the course development were D. Kennedy's learning outcomes theory and the concept of soft skills development. Structure, content and technology of the course are being tested in the process of training PhD students and young researchers at universities in Russia and Belarus. Introduction of the course is planned in the practice of the Doctoral Training Centers – Training centers for PhD students, organized at the universities of the MODEST project consortium (ERASMUS + program) in the countries: Russia; Belarus and Armenia.

Historical Analysis of the Example of Nowy Sącz in Space Syntax Perspective. Guidelines for Future Development of Urban Matrix in Medium-Sized Cities

This paper presents the development of the public space of Nowy Sącz, taking into account the space syntax analysis of the historical maps of the city and the structure of its development. Nowy Sącz is a city located in southern Poland, with over 80,000 residents. A space syntax analysis of historical maps helps to explain the urban space’s growth and development structure. The scientific goal of this paper was to build model solutions and urban typologies of Nowy Sącz; to present the logic of the model; and to compare simulation results with reality and historical knowledge. The application goal was to explain the processes and popularize the insight using clear space syntax visualizations. Axial maps of street networks were developed using current and historical city plans (publicly available plans from the late 18th century to the present day). The space syntax methodology was employed to measure Integration and Choice variables for each stage of the city’s spatial development. The results indicating areas of the highest Integration value were verified against historical studies. A strong correlation was demonstrated between the foci of urban life of super-local reach and their places in a growing city’s structural network.

Institutional model for ecotourism development in the Gunung Pongkor post-mining area

The Gunung Pongkor post-mining area has some resources potential for ecotourism destination. The development of area’s ecosystem in the Gunung Pongkor post-mining area needs to protect the ecosystem and prevent activities that do damage within the area. In this case, it is necessary to make institutional model for ecotourism development in the Gunung Pongkor post-mining area. The objectives of this study are 1) to identify the elements in the development structure variable; 2) to analyze objective variables, needs variables, constraint variables, and actor variables; 3) to create institutional model for ecotourism development in the Gunung Pongkor post-mining area. This study uses descriptive qualitative methods with Interpretive Structural Modelling (ISM) analysis. The elements analyzed are 1) the objectives to be achieved in the development of the ecotourism areas, 2) the needs in the development of the ecotourism areas, 3) the obstacles that need to be overcome, and 4) the actors who play a role in the development of the ecotourism areas. The key element of the goal for ecotourism development in the Gunung Pongkor post-mining area is to provide education to the local community about environmental management and culture. In the development process, a master plan and legality of the area as ecotourism are needed. Some of the main obstacles in the development of this area are the absence of a change in the status of a forest area to an ecotourism area and a lack of knowledge about the conservation of natural resources and the environment. The key actors needed in developing this area are Regional Planning, Research, and Development Agency of Bogor Regency Regional Government, Tourism and Culture Office of Bogor Regency Regional Government, Environmental Office of Bogor Regency Regional Government. The diversity of the existing potential is utilized to the fullest it resolves problem that occur in this area in achieving an ecotourism area based on landscape characters in the Gunung Pongkor post-mining through collaborative ecotourism development.