Therapy Of Infectious Diseases Research Articles

Cowpathy: A novel and potential source of new anti-microbial agents / strategies

Progressive increase in anti-microbial resistance made the future of infectious disease treatment worrisome. Although anti-microbial resistance is in existence since pre-antibiotic era, but indiscriminate use of antibiotics has accelerated its emergence and spread. This eminent threat to global ‘One Health’ suggested to limit the use of antibiotics and emphasized on the development of alternative treatment therapies for infectious diseases. The ancient Indian medicinal system i.e. Ayurveda, offers a library of antimicrobial solutions including use of herbal as well as animal products for infectious disease treatment. Different cow products such as cow urine, dung, milk, curd, ghee and Panchgavya have been reported to possess antimicrobial activities. Antimicrobial potential of these products have been attributed to different bioactive compounds including phenols, tannins, urea and supplemental elements. This article discusses the different studies related to antimicrobial potential of cow products, however, majority of these studies are preliminary and more research is required to explore the actual potential and to dive into the detailed mechanism of action. Keywords: Cow products, Antimicrobial potential, Antimicrobial resistance, Panchgavya, Infectious diseases

2022 AAFP/AAHA Antimicrobial Stewardship Guidelines.

2022 AAFP/AAHA Antimicrobial Stewardship Guidelines.

The in vitro and in vivo antibacterial activities of uniflorous honey from a medicinal plant, Scrophularia ningpoensis Hemsl., and characterization of its chemical profile with UPLC-MS/MS

Ethnopharmacological relevanceAccording to the Compendium of Materia Medica, honey has been used as a traditional medicine in treatment against mucositis, tinea, hemorrhoids and psoriasis. In complementary medicine, due to its significant antimicrobial activity, honey has been widely used as a remedy for skin wounds and gastrohelcosis for thousands of years. Aim of the studyThis study is aimed at exploring the antimicrobial activity and mechanisms of honey sourced from medicinal plants, and revealing the composition-activity relationship, to facilitate their complementary and alternative application in the therapy of bacterial infectious diseases. Materials and methodsEight kinds of medicinal plant-derived uniflorous honey, native to China, were gathered. Their antimicrobial activities were evaluated in vitro, and then in vivo with the systemically infected mouse model and the acute skin infection model. SYTOX uptake assay, scanning electron microscopy, DNA binding assay, and quantitative real-time PCR, were carried out to elucidate the antibacterial mechanisms. This was followed by an investigation of the componential profile with the UPLC-MS/MS technique. ResultsIt was found that Scrophularia ningpoensis Hemsl. (figwort) honey (S. ningpoensis honey) exhibited broad-spectrum and the strongest antibacterial potency (MICs of 7.81–125.00%, w/v), comparable to manuka honey. In the in vivo assays, S. ningpoensis honey significantly decreased the bacterial load of the muscles under the acute MRSA-infected skin wounds; the sera level of TNF-α in the S. aureus and P. aeruginosa-infected mice decreased by 45.38% and 51.75%, respectively, after the treatment of S. ningpoensis honey (125 mg/10 g). It was capable of killing bacteria through disrupting the cell membranes and the genomic DNA, as well as down-regulating the expression of genes associated with virulence, biofilm formation and invasion, including icaA, icaD, eno, sarA, agrA, sigB, fib and ebps in S. aureus, and lasI, lasR, rhlI, rhlR and algC in P. aeruginosa. Apart from H2O2, some other nonperoxide compounds such as adenosine, chavicol, 4-methylcatechol, trehalose, palmitoleic acid and salidroside, might play a vital role in the antibacterial properties of S. ningpoensis honey. ConclusionsThis is the first study to thoroughly investigate the antibacterial activity, mode of action, and componential profile of S. ningpoensis honey. It suggested that S. ningpoensis honey might be a potential supplement or substitute for manuka honey, for the prevention or treatment of bacterial infections. It will facilitate the precise application of medicinal plant-sourced honey, provide a new thread for the development of antibacterial drugs, and assist in the distinction of different kinds of honey.

ЦЕЛЫЙ ВЕК ВМЕСТЕ: К 100-летию ЖУРНАЛА «ПЕДИАТРИЯ. ЖУРНАЛ им. Г.Н. СПЕРАНСКОГО» И 95-летию СОЮЗА ПЕДИАТРОВ РОССИИ

This article is dedicated to the 100th anniversary of the Journal “PEDIATRIA. Journal named after G.N. Speransky,” which for more than half a century bears the name of its creator and permanent Editor-in-Chief for many decades – Georgiy Nestorovich Speransky. The article presents an overview of publications made throughout the history of the journal on the issues of diagnosis, therapy and prevention of infectious diseases in children.

Inverse optimal control for positive impulsive systems toward personalized therapeutic regimens

AbstractInfectious diseases are latent threats to humankind. Control theoretical approaches can help practitioners to advance the scheduling of drugs. For the case of infectious diseases, it is not possible to keep continuous flow of drug administration over all time‐steps, thus the action of the control input has to be restricted at some of the kth instants. This paper presents the adaptation of inverse optimal control to positive impulsive systems in discrete‐time to schedule therapies. The properties of positive systems are used to simplify the control design. Thus, the problem of scheduling therapies in infectious diseases is illustrated with influenza and COVID‐19. Numerical results show the applicability of the control algorithms.

A Dosing-Spoon-Based Electrochemical Sensor for Fast Assessment of Andrographis paniculata Extracts

Directly analyzing an herbal drug and its contamination is crucial to avoid severe problems due to uncertain dosages and unwanted contaminants. This article describes the first example of a dosing-spoon-based sensor for point-of-use detection of an herbal extract and its contamination. Andrographis paniculata is an herbal drug conventionally used for the therapy of many symptoms and infectious diseases, including COVID-19. The developed device consists of a sensitive electrochemical sensor, enabling the detection of A. paniculata extract. The lab-on-a-spoon squarewave voltammetric system provides the detection result with favorable sensitivity and simplicity in a short time (less than 15 s). The calibration curve of the modeled herbal extract covers a range of 0.030–7.350 mg ml–1 with a limit of detection of 20 μg ml–1. The device and data analysis were applied for determining real samples of A. paniculata extracts. The developed device is sensitive for the screening of processed products from A. paniculata. Moreover, this single dosing-spoon-based sensor can also simultaneously screen the contamination of heavy metals (i.e., cadmium and lead). We envision that this lab-on-a-spoon demonstration would expand the scope of portable pharmaceutical and biochemical sensors, offering promising convenient screening tools for industrial and household applications.

Management of antibacterial therapy of infectious and inflammatory diseases of the urinary tract in children and regional peculiarities during the COVID-19 pandemic.

Urinary tract infections (UTIs) remain an urgent issue in clinical pediatrics. Empirical selection of antibacterial therapy becomes more complicated, and antibacterial drug indication is not always clinically substantiated. This study aimed to compare the antibacterial susceptibility pattern of the main group of urinary tract infectious agents from 2009–2016 with intermediate results from 2020–2021, during the COVID-19 pandemic, among children in the Chernivtsi region. Urine samples were collected from 3089 children (0–17 years old) treated at the health care institutions in the Chernivtsi region (2009–2016). The clinical-laboratory examination of 177 children (0–17 years old) was carried out from 2020 to 2021. The children received specialized medical care at the Department of Nephrology. Preliminary data of regional monitoring (2020–2021) are not considerably different from the previous regional susceptibility of antibiotics: to penicillin (p<0.01), ІІ-ІІІ generation cephalosporin (p<0.01); an increased resistance to levofloxacin (χ2=4,338; p<0.01), tetracycline – χ2=7,277; p<0.01; doxycycline – χ2=5,309; p<0.01) and imipenem – χ2=5,594; p<0.01). The data obtained did not explain an increased resistance to fluoroquinolones completely (ofloxacin, pefloxacin, ciprofloxacin), except for levofloxacin (χ2=4,338; p<0.01). A reliable difference of susceptibility of tetracycline group was registered (tetracycline – χ2=7,277; p<0.01; doxycycline – χ2=5,309; p<0.01). Furthermore, there was a regional increase in some UTI-pathogen strains resistant to carbapenems (imipenem – χ2=5,594; p<0.01). The use of antibiotics from the group of penicillins and II-III generation cephalosporins as the starting antibacterial therapy for STIs during the COVID-19 pandemic should be justified. A regional increase (2020–2021) of some uropathogenic strains resistant to carbapenems administered to treat severe bacterial infections requires their exclusively designated purpose in everyday pediatric practical work.

Is a shorter course of antibiotics better for children with CAP?

Results of the SCOUT-CAP randomized clinical trial published in the January 2022 issue of JAMA Pediatrics found that a short 5-day antibiotic treatment course is superior to a standard 10-day regimen for children with non-severe community-acquired pneumonia (CAP) in an outpatient setting. A short 5-day strategy reduced both antibiotic exposure and resistance while presenting a similar clinical response and antibiotic-related adverse effect profile as a standard 10-day course. According to the study, CAP is one of the most common serious infections in pediatric populations, with reports of about 1.5 million ambulatory visits by U.S. children yearly. “It’s critical that we minimize the use of unnecessary antibiotics, both to eliminate the risk of antibiotic adverse effects and slow the progression of antimicrobial resistance, a global public health threat,” said Derek Williams, MD, MPH, lead investigator of the study. Although antibiotics are not always needed, when required it is important to choose the right antibiotic, at the right dose, and only for as long as necessary to effectively treat the infection, said Williams, who is an associate professor of pediatrics at Vanderbilt University School of Medicine. The randomized, double-blind, placebo-controlled clinical trial included 380 healthy children between the ages of 6 months and roughly 6 years with non-severe CAP in 8 U.S. cities between December 2016 and December 2019. They were seen in outpatient clinics, urgent care settings, and emergency departments. Children were only included in the study if they had not experienced the following at time of enrollment based on caregiver reporting: subjective fever or temperature 38.3°C or higher in the previous 24 hours; tachypnea (50 and 40 breaths per minute for children younger than 2 years, and 2 years and older, respectively); and severe cough. Study participants were randomized 1:1 to either receive a 5-day course of matching placebo or an additional 5-day course of the originally prescribed β-lactam antibiotic—including amoxicillin, amoxicillin and clavulanate, or cefdinir—on day 6 of therapy. Dosing for amoxicillin or amoxicillin and clavulanate was 80 to 100 mg/kg a day (maximum 2,000 mg a day) based on the amoxicillin component divided twice daily, and cefdinir dosing was 12 to 16 mg/kg a day (maximum 600 mg a day) divided twice daily. The taste and appearance of the matching placebo was consistent and dosed at the same interval as the original 5-day course therapy. Study participants underwent two in-person outcome assessment visits on study days 6 to 10 and days 19 to 25, respectively. The primary composite endpoint—a ranking of each child’s clinical response, symptom resolution, and antibiotic-associated adverse effects—made up the end-of-treatment response adjusted for duration of antibiotic risk (RADAR) in an ordinal desirability of outcome ranking (DOOR). Participants were then ranked by the number of antibiotic days within each DOOR, with the hypothesis that shorter antibiotic durations were more desirable. RADAR was used to determine the more desirable outcome probability estimate for short- versus standard-course strategy. During the antibiotic resistance analysis, throat swab samples were taken from the oropharyngeal flora of 171 children between days 19 and 25 to assess antibiotic resistance. The research findings showed that a majority of children had an adequate clinical response to both strategies, with fewer than 10% of children experiencing a poor response. The research team found that the short-course strategy had a 69% probability of a more desirable RADAR outcome compared with the standard-course strategy. The antibiotic resistance analysis showed that the range of antibiotic resistance genes per prokaryotic cell (RGPC) was significantly lower in the short-course strategy compared with the standard-course strategy for total RGPC and β-lactamase RGPC, according to the study. “SCOUT-CAP is the first clinical trial to use this innovative trial design, taking into account both the response to and potential side effects of antibiotic therapy,” said C. Buddy Creech, MD, MPH, a professor of pediatrics at Vanderbilt University Medical Center, who was also part of the study. “These data are immediately applicable to frontline clinicians, and we hope it helps to shift the paradigm for childhood pneumonia toward more judicious treatment approaches, resulting in safer and more effective care,” said Williams. Future trials using this approach may allow us to optimize therapy for other infectious diseases in children and adults, said Creech.

Mutually Exclusive Interactions of Rifabutin with Spatially Distinct Mycobacterial Cell Envelope Membrane Layers Offer Insights into Membrane-Centric Therapy of Infectious Diseases.

The mycobacterial cell envelope has spatially resolved inner and outer membrane layers with distinct compositions and membrane properties. However, the functional implication and relevance of this organization remain unknown. Using membrane biophysics and molecular simulations, we reveal a varied interaction profile of these layers with antibiotic Rifabutin, underlined by the structural and chemical makeup of the constituent lipids. The mycobacterial inner membrane displayed the highest partitioning of Rifabutin, which was located exclusively in the lipid head group/interfacial region. In contrast, the drug exhibited specific interaction sites in the head group/interfacial and hydrophobic acyl regions within the outer membrane. Altogether, we show that the design of membrane-active agents that selectively disrupt the mycobacterial outer membrane structure can increase drug uptake and enhance intracellular drug concentrations. Exploiting the mycobacterium-specific membrane–drug interaction profiles, chemotypes consisting of outer membrane-disruptive agents and antitubercular drugs can offer new opportunities for combinational tuberculosis (TB) therapy.

Utilization of point-of-care tests among general practitioners, a cross-sectional study

BackgroundPoint-of-care testing (POCT) has numerous potential benefits to improve health care service, especially in resource-limited settings. We aim to identify which POC-tests (POCTs) of laboratory parameters are known, employed, and rated as useful by general practitioners (GPs).MethodsA questionnaire with 27 POCTs was posted to a random selection of GPs (n = 451) in Saxony, Germany.ResultsA total of 208 GPs replied (response rate 46.1%). Out of 27 POCTs, each GP knew an average of 20.3 as laboratory parameters and 9.2 as POCTs. Urine test strips (99.0%), blood glucose test (98.1%), and Troponin I/T (86.4%) were the best-known, followed by INR/Quick (82.5%), Microalbumin (79.1%), and D-dimer (78.6%) POCTs. Yet, solely 0 to 13 POC tests were actually used (mean value 4.6). Urine test strips were employed most frequently (97.6%), followed by blood glucose test (94.7%), Troponin I/T (57.8%), Microalbumin (57.3%), and INR/Quick POCTs (41.7%). Heart fatty binding protein (H-FABP), Syphilis, Coeliac disease, and Malaria appeared as the least frequently used POCTs. The majority of the GPs declared 14 of the 27 POCTs to be useful.Discussion/conclusionThe most recurrently employed POCTs are those for diagnosing or monitoring diabetes mellitus, ensued by POCTs addressing acute cardiovascular diseases (Troponin I/T, D-dimer) or monitoring the therapy of infectious diseases or the anticoagulant therapy. POCTs most often rated as useful by GPs are also widely known and frequently used. Nonetheless, the majority of GPs rate only a very limited number of POCTs as useful. Frequent concerns might be low economic benefit, over-reliance, and test accuracy coming along with the complex implementation of the tests requiring technical skills, accurate storage, and the correct interpretation of test results.Trial registrationIn accordance with the (Model) Professional Code for Physicians in Germany, neither human body materials nor data that can be assigned to a specific human being are used in our study. A declaration of no objection from the Ethics Committee of the Martin-Luther University Halle-Wittenberg (Medical Faculty) confirms no professional or ethical concerns due to completely anonymized data collection and analysis. Our study was therefore not registered in a corresponding registry.

Phytochemical Composition and Potential Bioactivities of the Essential Oil from the Peels of Paramignya trimera (Oliv.) Guillaum from Vietnam

Paramignya trimera (Oliv.) Guillaum (Xao tam phan), found mostly in South Vietnam, is a herbal medicine traditionally used for liver protection ability and dermatologic diseases. Recent studies showed that different extracts, fractions and isolated compounds from P. trimera exhibited many interesting bioactivities such as antioxidant, anticancer, anti-inflammatory and alpha-glucosidase inhibitory activities. However, research on the chemical profile and bioactivities of essential oil from the peels of this species has been limited. Therefore, this study aims to determine the chemical composition of this product and examine its anticancer and antibacterial activities. Phytochemical profile of the essential oil was analyzed using gas chromatography coupled to mass spectrometry. Indeed, twenty-four constituents were characterized; of which sesquiterpenes dominated the profile, with three major compounds: β-caryophyllene (19.09%), α-humulene (24.81%), and trans-muurola-4(14),5-diene (24.84%). P. trimera peel essential oil also contained potent inhibitory effects against six clinical multidrug-resistant bacterial strains including both Gram-positive and Gram-negative bacteria. This extract showed the strongest activity against two Pseudomonas aeruginosa strains with minimum inhibitory concentration (MIC) of 256 µg/mL for both, followed by 2 strains of Staphylococcus aureus and 2 strains of Salmonella sp. with MIC values of 384, 480 and 512 µg/mL, respectively. In addition, P. trimera peel essential oil displayed strong cytotoxicity in a dose-dependent manner against liver HepG2 cancer cells, with the half maximal inhibitory concentration of 21 µg/mL. This preliminary result suggested the potential bioactivities of P. trimera peel essential oil and can be helpful for further investigation to develop an phytomedicine-based therapy for cancer and infectious diseases.

Prodrug Therapies for Infectious and Neurodegenerative Diseases.

Prodrugs are bioreversible drug derivatives which are metabolized into a pharmacologically active drug following chemical or enzymatic modification. This approach is designed to overcome several obstacles that are faced by the parent drug in physiological conditions that include rapid drug metabolism, poor solubility, permeability, and suboptimal pharmacokinetic and pharmacodynamic profiles. These suboptimal physicochemical features can lead to rapid drug elimination, systemic toxicities, and limited drug-targeting to disease-affected tissue. Improving upon these properties can be accomplished by a prodrug design that includes the careful choosing of the promoiety, the linker, the prodrug synthesis, and targeting decorations. We now provide an overview of recent developments and applications of prodrugs for treating neurodegenerative, inflammatory, and infectious diseases. Disease interplay reflects that microbial infections and consequent inflammation affects neurodegenerative diseases and vice versa, independent of aging. Given the high prevalence, personal, social, and economic burden of both infectious and neurodegenerative disorders, therapeutic improvements are immediately needed. Prodrugs are an important, and might be said a critical tool, in providing an avenue for effective drug therapy.

Nanoparticle, a promising therapeutic strategy for the treatment of infective endocarditis.

Infective endocarditis (IE) has been recognized as a biofilm-related disease caused by pathogenic microorganisms, such as bacteria and fungi that invade and damage the heart valves and endocardium. There are many difficulties and challenges in the antimicrobial treatment of IE, including multi-drug resistant pathogens, large dose of drug administration with following side effects, and poor prognosis. For the past few years, the development of nanotechnology has promoted the use of nanoparticles as antimicrobial nano-pharmaceuticals or novel drug delivery systems (NDDS) in antimicrobial therapy for chronic infections and biofilm-related infectious disease as these molecules exhibit several advantages. Therefore, nanoparticles have a potential role to play in solving problems in the treatment of IE, including improving antimicrobial activity, increasing drug bioavailability, minimizing frequency of drug administration, and preventing side effects. In this article, we review the latest advances in nanoparticles against drug-resistant bacteria in biofilm and recommends nanoparticles as an alternative strategy to the antibiotic treatment of IE.

Increased Activities against Biofilms of the Pathogenic Yeast Candida albicans of Optimized Pom-1 Derivatives.

Antimicrobial peptides (AMPs) are an alternative group for the therapy of infectious diseases, with activity against a wide range of diverse pathogens. However, classical AMPs have significant side effects in human cells due to their unspecific pore formation in biomembranes. Nevertheless, AMPs are promising therapeutics and can be isolated from natural sources, which include sea and freshwater molluscs. The AMPs identified in these organisms show promising antimicrobial activities, as pathogens are mainly fought by innate defence mechanisms. An auspicious candidate among molluscs is the Cuban freshwater snail Pomacea poeyana, from which the peptides Pom-1 and Pom-2 have been isolated and studied. These studies revealed significant antimicrobial activities for both AMPs. Based on the activities determined, Pom-1 was used for further optimization. In order to meet the emerging requirements of improved anti-biofilm activity against naturally occurring Candida species, the six derivatives Pom-1A to F were developed and investigated. Analysis of the derivatives acting on the most abundant naturally occurring Candida yeast Candida albicans (C. albicans) revealed a strong anti-biofilm activity, especially induced by Pom-1 B, C, and D. Furthermore, a moderate decrease in the metabolic activity of planktonic yeast cells was observed.

The association of high Vancomycin trough concentration with acute kidney injury during combination therapy of Piperacillin/Tazobactam and Vancomycin

BackgroundCo-administration of Piperacillin/Tazobactam (PIPC/TAZ) and Vancomycin (VCM) as an antibiotic therapy for severe infectious diseases increases the risk of nephrotoxicity. We retrospectively investigated the utility of monitoring VCM trough concentration in early stage of developing acute kidney injury (AKI) on this combination therapy. MethodsWe enrolled all infectious disease patients who were managed with concurrent PIPC/TAZ and VCM. The record of dosage and the administration interval of each antibiotic and its clinical parameters, as well as the VCM trough concentrations, blood culture for bacteria, and serum creatinine values, were collected. VCM trough concentration was measured during the initial 48–72 h of VCM administration. Nephrotoxicity was evaluated as the degree of AKI. ResultsA total of 47 patients fulfilling the criteria were registered, and AKI developed in 10 patients. There was no statistical difference between the AKI and non-AKI groups with regard to age, height, weight, basal creatinine level, body surface area, body mass index, PIPC/TAZ dose, VCM dose, gender, artificial management, and death within around 30 days. The VCM trough level was increased significantly in the AKI group (mean [standard deviation {SD}]: 25.9 [7.8] μg/mL) compared to that in the non-AKI group (mean [SD]: 15.7 [6.9] μg/mL) (p = 0.003). During the clinical course, renal function returned to normal levels in three out of four AKI stage 2 patients, whereas only partial recovery was achieved in all AKI stage 3 patients. ConclusionsA high VCM trough concentration may have an influence on the occurrence of AKI during combination therapy of PIPC/TAZ and VCM. Careful monitoring of VCM trough concentration will be required to prevent AKI progression.

Prospects of using chondroprotectors for the treatment of pulmonary pathology

Background.The complex mechanisms of action of chondroitin sulfate (CS) and glucosamine sulfate (GS) at the molecular level make it possible to assert the applicability of the corresponding drugs far beyond chondroprotection. Inhibition of proinflammatory mechanisms (NF-κB, activation of toll-receptors, increased levels of cytokines, degranulation of mast cells, etc.) by CS and GS provide the prospects for their use to inhibit inflammation in the respiratory tracts, allergic processes and to enhance the effects of glucocorticoids.Objective:to systemize data on the effects of chondroitin sulfate and glucosamine sulfate on pathophysiological processes in pulmonary pathology.Material and methods.Using the methods of the theory of text topological analysis an intellectual analysis of 1273 publications on fundamental and clinical studies of the relationship of CS and GS with lung function was carried out. The search was performed by a key query “(glucosamine OR chondroitin) AND (lung OR lungs OR pulmonary OR pulmonology)” in the Pubmed/MEDLINE database. As a result, 59 informative biomedical terms were identified.Results.The chemoproteomic study of CS and GS showed that their intake promoted an increase in the expression of 19 antitumor proteins and a decrease in the expression of 25 pro-inflammatory proteins involved in lung function. CS and GS can be used in the complex therapy of infectious diseases of the lungs, with fibrotic changes in the respiratory tracts and, as well, help to reduce the risk of neoplastic diseases of the lungs.Conclusion.The results of this analysis allow us to assert the promising nature of the use of CS and GS in several neoplastic diseases of the lungs, as well as the high safety of drugs based on pharmaceutical standardized forms of CS and GS in terms of lung function.

Pulmonary delivery of mucosal nanovaccines.

Mucosal vaccination can elicit both systemic and mucosal immunity, and therefore has the potential to not only treat mucosal immune diseases, prevent the pathogen infection at the mucosal entry sites, but also treat distant or systemic immune disorders. However, only a few mucosal vaccines have been approved for human use in the clinic. Effective mucosal immunization requires the delivery of immunogenic agents to appropriate mucosal surfaces, which remains significantly challenging due to the essential biological barriers presenting at mucosal tissues. In the past decade, remarkable progress has been made in the development of pulmonary mucosal nanovaccines. The nanovaccines leverage advanced nanoparticle-based pulmonary delivery technologies on the characteristics of large surface area and rich antigen presentation cell environment of the lungs for triggering robust immune protection against various mucosal diseases. Herein, we review current methods and formulations of pulmonary delivery, discuss the design strategies of mucosal nanovaccines for potent and long-lasting immune responses, and highlight recent advances in the application of lipid-based pulmonary nanovaccines against mucosal diseases. These advances promise to accelerate the development of novel mucosal nanovaccines for the prophylaxis and therapy of infectious diseases, and cancer, as well as autoimmune disorders at mucosal tissues.

Microbiome-based therapeutics: Opportunity and challenges.

The autochthonous microbial communities comprising symbionts, commensals, and opportunistic pathogens living throughout the human body profoundly contribute to health by reducing disease susceptibility and maturing host immunity. The community compositions and functional repertoires of microbiomes present in the different body habitats are dynamic. The structural and functional balance of the human microbiome could be modulated by environmental factors, lifestyle, and host genetics. Several functions of the microbial community directly or indirectly modulate host cellular signaling pathways that are associated with energy assimilation, sensing and responding to environmental signals through the neuroendocrine pathways, and resistance against colonization of allochthonous microbiota with disease-causing potential. Both culture-dependent and independent characterizations of microbial community compositions and their functional attributes help us to recognize the importance of microbial diversity in individual's health and identify the microbes and their metabolites associated with health and diseases. Such an in-depth understanding of the human microbiome created avenues of microbiome-based translation research, which led to the discovery and development of large numbers of medical therapies. In this chapter, we discuss the current success of microbiome-based therapies for infectious and metabolic diseases, and the major bottleneck and challenges of translational research with the community of symbiotic microorganisms.

DNA Methylation in Prokaryotes.

The genomes of bacteria, archaea, and phage contain small amounts of C5-methylcytosine, N4-methylcytosine, and N6-methyladenine. Base methylation takes place after DNA replication and is catalyzed by DNA methyltransferases that recognize specific target sequences. Prokaryotic DNA methyltransferases can be classified into two main types: (1) belonging to restriction-modification systems and (2) solitary (or "orphan") enzymes that lack a restriction enzyme partner. All known roles of DNA methylation involve control of interactions between DNA-binding proteins and their cognate sites. Such roles include protection from DNA restriction, strand discrimination during mismatch repair, cell cycle control, and regulation of transcription. DNA methylation often affects the interaction of bacterial pathogens with their hosts, raising the possibility of epigenetic therapies for infectious diseases.

Характеристика CRISPR/CAS-системы штамма Pseudomonas aeruginosa DSM 50071 на основе биоинформационного анализа её структур

An algorithm for bioinformatic search and analysis of the structures of CRISPR/Cas systems of bacteria and screening of phages and plasmids through spacer sequences of CRISPR cassettes in the genome of the Pseudomonas aeruginosa strain DSM 50071 is presented.Using several search algorithms in the CRISPR/Cas system of the studied strain, the presence of three CRISPR loci and a group of Cas genes characteristic of Type-I Subtype-I-F was determined.Analysis of the spacer composition of CRISPR cassettes showed the presence of 31 to 43 spacers and a universal consensus repeat in all cassettes.Screening of the spacer sequences of the CRISPR cassettes of the studied strain showed their correspondence to the protospacers of phages and plasmids of bacteria of the families Pseudomonadaceae and Enterobacteriaceae. A complete characterization of bacteriophages to which this strain is resistant is given with their accession number in NCBI. A complete identification of spacers to protospacers of phages specific for bacteria of the Pseudomonadaceae family, most often isolated from the lungs of patients with bronchiectasis, pneumonia, as well as from hospitals and reservoirs, has been established.Full correspondence between spacers and protospacers of bacterial plasmids with pan-resistance and causing the development of respiratory failure and pneumonia was revealed. Correspondence of a segment of one spacer with protospacers of several bacterial phages of the same family was noted. This may indicate that the bacterium “expediently” acquires new spacers from DNA regions that are conserved for phages of bacteria of the same family.Genes that have phage protospacers in their structure have been identified.It has been established that these genes are responsible for the synthesis of enzymes that regulate the processes of virus reproduction.Therefore, activation of the CRISPR/Cas system in the genome of this strain will allow the restriction endonuclease to introduce breaks into unmethylated DNA, which will lead to disruption of the synthesis of this enzyme, and, consequently, disruption of bacteriophage replication.Correspondences of spacer sequences with protospacers of plasmids included in the structure of genes responsible for the synthesis of conjugative transfer enzymes were revealed.These results suggested that activation of the CRISPR/Cas system of this strain would disrupt the processes replication of bacteriophage and conjugation.The proposed algorithm made it possible to obtain information about the structure of the CRISPR/Cas system of the P. aeruginosa DSM 50071 strain, about its resistance to certain phages and plasmids. In the future, this will serve as the basis for creating approaches for targeted therapy of infectious diseases.