42 research outputs found
QUEST TECHNOLOGY AS A WAY OF SOCIAL AND CULTURAL ADAPTATION OF FOREIGN STUDENTS AT THE LESSONS OF RUSSIAN AS A FOREIGN LANGUAGE
The relevance of the article is determined by the need to define effective and relevant ways of acquaintance of foreign students with the realities of the new social culture, which will subsequently have a beneficial effect on the learning outcome. The purpose of the article is to systematically present ways of working with quest technology in foreign language classes, which are aimed at increasing the level of socio-cultural adaptation of foreign speakers in the new language and cultural community. The methodology of the present study is civilizational and cultural approaches, the work uses a logical method (theoretical), the study of the experience of educational organizations and personal pedagogical experience at the University (empirical).The author came to the conclusion that the modern educational process of training at the preparatory Department of the University should be aimed not only at achieving the necessary level of linguistic training, but also at the gradual systematic immersion of foreigners in a new socio-cultural environment through language. One of the most popular technologies in pedagogy is the quest that includes both solving a problem task and independent search for information. Educational quest in a foreign language at pre-University stage of education is the most effective, because it can be used at any level of language training, it perfectly solves the problem of language education and formation of speech culture, socio-cultural adaptation of foreign students in the conditions of the new region and explore the national cultural realities that undoubtedly contributes to a better understanding of internal and external communications companies.
Antibiofilm Peptides and Peptidomimetics with Focus on Surface Immobilization
Bacterial biofilms pose a major threat to public health, as they are associated with at least two thirds of all infections. They are highly resilient and render conventional antibiotics inefficient. As a part of the innate immune system, antimicrobial peptides have drawn attention within the last decades, as some of them are able to eradicate biofilms at sub-minimum inhibitory concentration (MIC) levels. However, peptides possess a number of disadvantages, such as susceptibility to proteolytic degradation, pH and/or salinity-dependent activity and loss of activity due to binding to serum proteins. Hence, proteolytically stable peptidomimetics were designed to overcome these drawbacks. This paper summarizes the current peptide and peptidomimetic strategies for combating bacteria-associated biofilm infections, both in respect to soluble and surface-functionalized solutions
Neuropsychological Disorders Indicative of Postresuscitation Encephalopaty in Rats
El propósito de este estudio fue examinar el efecto de una muerte clínica de 12 minutos de duración sobre el comportamiento innato y adquirido, la concentración amino biogénica, y la composición y cantidad de las poblaciones neuronales en regiones específicas en ratas blancas. El estudio muestra que durante el período con restauración formal del estatus neurológico, hay cambios en los animales en la reactividad emocional, las reacciones de orientación-exploración, trastornos de aprendizaje y memoria, reducción de la tolerancia al ejercicio y la sensibilidad al dolor. Estos procesos se acompañan de alteraciones en los niveles de serotonina y norepinefrina en la corteza cerebral frontal, en los niveles de dopamina y serotonina en el cuerpo estriado, ciertos índices bioquímicos en el plasma sanguíneo y pérdida neuronal en el sector CA1 del hipocampo y en porciones laterales del cerebelo.The aim of this research was to study the effect of 12-minute clinical death on innate and acquired behavior, biogenic amine concentration, and the composition and quantity of neural populations in specific brain regions of white rats. The study shows that in animals during the postresuscitation period with formal restoration of neurological status, there are changes in emotional reactivity, orientation-exploration reactions, impairment of learning and memory, decrease in exercise tolerance and pain sensitivity. These processes are accompanied by alterations in serotonin and norepinephrine levels in the frontal cerebral cortex, dopamine and serotonin levels in the striatum, certain biochemical indices in blood plasma and neural loss in the CA1 sector of the hippocampus and lateral portions of the cerebellum
Halogenation as a tool to tune antimicrobial activity of peptoids
Abstract
Antimicrobial peptides have attracted considerable interest as potential new class of antibiotics against multi-drug resistant bacteria. However, their therapeutic potential is limited, in part due to susceptibility towards enzymatic degradation and low bioavailability. Peptoids (oligomers of N -substituted glycines) demonstrate proteolytic stability and better bioavailability than corresponding peptides while in many cases retaining antibacterial activity. In this study, we synthesized a library of 36 peptoids containing fluorine, chlorine, bromine and iodine atoms, which vary by length and level of halogen substitution in position 4 of the phenyl rings. As we observed a clear correlation between halogenation of an inactive model peptoid and its increased antimicrobial activity, we designed chlorinated and brominated analogues of a known peptoid and its shorter counterpart. Short brominated analogues displayed up to 32-fold increase of the activity against S. aureus and 16- to 64-fold against E. coli and P. aeruginosa alongside reduced cytotoxicity. The biological effect of halogens seems to be linked to the relative hydrophobicity and self-assembly properties of the compounds. By small angle X-ray scattering (SAXS) we have demontrated how the self-assembled structures are dependent on the size of the halogen, degree of substitution and length of the peptoid, and correlated these features to their activity
Correlation between hemolytic activity, cytotoxicity and systemic in vivo toxicity of synthetic antimicrobial peptides
Membrane‐acting biomimetic peptoids against visceral leishmaniasis
Visceral leishmaniasis (VL) is among the most neglected tropical diseases in the world. Drug cell permeability is essential for killing the intracellular residing parasites responsible for VL, making cell-permeating peptides a logical choice to address VL. Unfortunately, the limited biological stability of peptides restricts their usage. Sequence-specific oligo-N-substituted glycines (‘peptoids’) are a class of peptide mimics that offers an excellent alternative to peptides in terms of ease of synthesis and good biostability. We tested peptoids against the parasite Leishmania donovani in both forms, that is, intracellular amastigotes and promastigotes. N-alkyl hydrophobic chain addition (lipidation) and bromination of oligopeptoids yielded compounds with good antileishmanial activity against both forms, showing the promise of these antiparasitic peptoids as potential drug candidates to treat VL
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Antiviral Effect of Antimicrobial Peptoid TM9 and Murine Model of Respiratory Coronavirus Infection
New antiviral agents are essential to improving treatment and control of SARS-CoV-2 infections that can lead to the disease COVID-19. Antimicrobial peptoids are sequence-specific oligo-N-substituted glycine peptidomimetics that emulate the structure and function of natural antimicrobial peptides but are resistant to proteases. We demonstrate antiviral activity of a new peptoid (TM9) against the coronavirus, murine hepatitis virus (MHV), as a closely related model for the structure and antiviral susceptibility profile of SARS-CoV-2. This peptoid mimics the human cathelicidin LL-37, which has also been shown to have antimicrobial and antiviral activity. In this study, TM9 was effective against three murine coronavirus strains, demonstrating that the therapeutic window is large enough to allow the use of TM9 for treatment. All three isolates of MHV generated infection in mice after 15 min of exposure by aerosol using the Madison aerosol chamber, and all three viral strains could be isolated from the lungs throughout the 5-day observation period post-infection, with the peak titers on day 2. MHV-A59 and MHV-A59-GFP were also isolated from the liver, heart, spleen, olfactory bulbs, and brain. These data demonstrate that MHV serves as a valuable natural murine model of coronavirus pathogenesis in multiple organs, including the brain
Personalizing the Way of Teaching LSP
Introduction. The problem of effective teaching language for special purposes (LSP) to the students of non-linguistic professions has been discussed for a long time and in full details by academicians both in Russia and foreign countries. As the result of multiple and thorough surveys general problems of the given situation have been revealed, the way out being defined as special training/retraining of LSP teachers. But in language education publications it is hardly possible to find the description of the program aiming at the training of the above mentioned teachers. The aim of the article is to present effective approaches to teaching LSP and offer the developed master program “Methods of teaching LSP” as a means to solve the problems mentioned above.
Materials and Methods. The research methods used are a combination of analytical review of studies by Russian and foreign researchers and interpretation of the results obtained by interviewing university teachers specializing in teaching foreign languages to students completing Bachelorʼs or Masterʼs degree programs. The survey was conducted to assess the level of readiness of professional educators to design the structure and content of programs for teaching LSP, and actually conduct classes within the specified language-teaching area, 81 teachers being responders.
Results. As a result of the undertaken review of theoretical works and analysis of the conducted survey a master program “Methods of teaching LSP” was designed for training graduates who will then teach English or Russian as a foreign language at industry-specific higher schools. The developed program focuses on instructing future LSP educators to work out a personalized educational route adjusted to the level of foreign language skills of a student and their prospective professional activities.
Discussion and Conclusion. The master program developed by the authors as well as the content of the subjects suggested as its integral part are expected to become a productive way of training LSP educators who are supposed to acquire a number of special skills and competences described in the article. Distant learning and e-learning technologies are also engaged in the program to facilitate learners’ more efficient independent activities. The master program is seen as one of the means of modernizing LSP teachers’ professional training which meets the long-term needs of the Russian education system
Anti-persister and Anti-biofilm Activity of Self-Assembled Antimicrobial Peptoid Ellipsoidal Micelles
[Image: see text] Although persister cells are the root cause of resistance development and relapse of chronic infections, more attention has been focused on developing antimicrobial agents against resistant bacterial strains than on developing anti-persister agents. Frustratingly, the global preclinical antibacterial pipeline does not include any anti-persister drug. Therefore, the central point of this work is to explore antimicrobial peptidomimetics called peptoids (sequence-specific oligo-N-substituted glycines) as a new class of anti-persister drugs. In this study, we demonstrate that one particular antimicrobial peptoid, the sequence-specific pentamer TM5, is active against planktonic persister cells and sterilizes biofilms formed by both Gram-negative and Gram-positive bacteria. Moreover, we demonstrate the potential of TM5 to inhibit cytokine production induced by lipopolysaccharides from Gram-negative bacteria. We anticipate that this work can pave the way to the development of new anti-persister agents based on antimicrobial peptoids of this class to simultaneously help address the crisis of bacterial resistance and reduce the occurrence of the relapse of chronic infections
Antimicrobial Activity of α-Peptide/β-Peptoid Lysine-Based Peptidomimetics Against Colistin-Resistant Pseudomonas aeruginosa Isolated From Cystic Fibrosis Patients
Pseudomonas aeruginosa infection is a predominant cause of morbidity and mortality in patients with cystic fibrosis infection and with a compromised immune system. Emergence of bacterial resistance renders existing antibiotics inefficient, and therefore discovery of new antimicrobial agents is highly warranted. In recent years, numerous studies have demonstrated that antimicrobial peptides (AMPs) constitute potent agents against a range of pathogenic bacteria. However, AMPs possess a number of drawbacks such as susceptibility to proteolytic degradation with ensuing low bioavailability. To circumvent these undesired properties of AMPs unnatural amino acids or altered backbones have been incorporated to provide stable peptidomimetics with retained antibacterial activity. Here, we report on antimicrobial α-peptide/β-peptoid lysine-based peptidomimetics that exhibit high potency against clinical drug-resistant P. aeruginosa strains obtained from cystic fibrosis patients. These clinical strains possess phoQ and/or pmrB mutations that confer high resistance to colistin, the last-resort antibiotic for treatment of infections caused by P. aeruginosa. The lead peptidomimetic LBP-2 demonstrated a 12-fold improved anti-pseudomonal activity as compared to colistin sulfate as well as favorable killing kinetics, similar antibiofilm activity, and moderate cytotoxicity