Interaction of the viral infectious agents in the development and exacerbation of the multiple sclerosis.

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disorder of the central nervous system (CNS). The underlying cause of MS is still unknown. Multiple risk factors have been suggested that involve a combination of genetic, environmental, and infectious factors that contribute along with a weakened immune system. There is growing evidence supporting the potential role of viral infections in the development of the disease. Viruses like human immunodeficiency virus (HIV), John Cunningham virus (JCV), Varicella-Zoster virus (VZV), human herpesvirus 6 (HHV-6), Epstein-Barr virus (EBV), and human endogenous retroviruses (HERVs) have been proposed in the pathogenesis of MS. Their pathogenetic mechanisms are not well known, but several possibilities have been discussed. The present study highlights the proposed potential molecular and genetic mechanisms underlying this viral interaction and its implications for the development of MS.

A Critical Review on Akkermansia muciniphila: Functional Mechanisms, Technological Challenges, and Safety Issues.

Due to its physiological benefits from in vitro and in vivo points of view, Akkermansia muciniphila, a common colonizer in the human gut mucous layer, has consistently been identified as an option for the next-generation probiotic. A. muciniphila is a significant bacterium that promotes host physiology. However, it also has a great deal of potential to become a probiotic due to its physiological advantages in a variety of therapeutic circumstances. Therefore, it can be established that the abundance of A. muciniphila in the gut environment, which is controlled by many genetic and dietary variables, is related to the biological behaviors of the intestinal microbiota and gut dysbiosis/eubiosis circumstances. Before A. muciniphila is widely utilized as a next-generation probiotic, regulatory obstacles, the necessity for significant clinical trials, and the sustainability of manufacturing must be eliminated. In this review, the outcomes of recent experimental and clinical reports are comprehensively reviewed, and common colonization patterns, main factors involved in the colonization of A. muciniphila in the gut milieu, their functional mechanisms in establishing homeostasis in the metabolic and energy pathways, the promising delivery role of microencapsulation, potential genetic engineering strategies, and eventually safety issues of A. muciniphila have been discussed.

A critical review of novel antibiotic resistance prevention approaches with a focus on postbiotics.

Antibiotic resistance is a significant public health issue, causing illnesses that were once easily treatable with antibiotics to develop into dangerous infections, leading to substantial disability and even death. To help fight this growing threat, scientists are developing new methods and techniques that play a crucial role in treating infections and preventing the inappropriate use of antibiotics. These effective therapeutic methods include phage therapies, quorum-sensing inhibitors, immunotherapeutics, predatory bacteria, antimicrobial adjuvants, haemofiltration, nanoantibiotics, microbiota transplantation, plant-derived antimicrobials, RNA therapy, vaccine development, and probiotics. As a result of the activity of probiotics in the intestine, compounds derived from the structure and metabolism of these bacteria are obtained, called postbiotics, which include multiple agents with various therapeutic applications, especially antimicrobial effects, by using different mechanisms. These compounds have been chosen in particular because they don't promote the spread of antibiotic resistance and don't include substances that can increase antibiotic resistance. This manuscript provides an overview of the novel approaches to preventing antibiotic resistance with emphasis on the various postbiotic metabolites derived from the gut beneficial microbes, their activities, recent related progressions in the food and medical fields, as well as concisely giving an insight into the new concept of postbiotics as "hyperpostbiotic".

The metabolic, protective, and immune functions of Akkermansia muciniphila.

Numerous studies have almost proven the beneficial effects of gut microbiota in various aspects of human health, and even the gut microbiota is known as a new and forgotten organ. Akkermansia muciniphila, as a member of the gut microbiota, is considered a bacterium with probiotic properties; consequently, it has a remarkable position in microbiome research. This bacterium accounts for about 1-4 % of the total fecal microbiota population and is also considered a health marker. The accumulated evidence has shown a significant association between A. muciniphila and several disorders and diseases, such as obesity, fatty liver disease, diabetes, and even behavioral disorders. On the other hand, the beneficial effects of A. muciniphila in different studies have shown, such as protective role against pathogenic agents, antitumor properties, tight junctions' improvement, reduction of inflammation, gut permeability, and boosting adaptive immune responses. In this review, based on the available evidence and the latest research, we comprehensively evaluated the impact of A. muciniphila on host health from three points of view: metabolic, protective, and immune functions, as well as the possible mechanisms of each process.

Postbiotics as the new frontier in food and pharmaceutical research.

Food is the essential need of human life and has nutrients that support growth and health. Gastrointestinal tract microbiota involves valuable microorganisms that develop therapeutic effects and are characterized as probiotics. The investigations on appropriate probiotic strains have led to the characterization of specific metabolic byproducts of probiotics named postbiotics. The probiotics must maintain their survival against inappropriate lethal conditions of the processing, storage, distribution, preparation, and digestion system so that they can exhibit their most health effects. Conversely, probiotic metabolites (postbiotics) have successfully overcome these unfavorable conditions and may be an appropriate alternative to probiotics. Due to their specific chemical structure, safe profile, long shelf-life, and the fact that they contain various signaling molecules, postbiotics may have anti-inflammatory, immunomodulatory, antihypertensive properties, inhibiting abnormal cell proliferation and antioxidative activities. Consequently, present scientific literature approves that postbiotics can mimic the fundamental and clinical role of probiotics, and due to their unique characteristics, they can be applied in an oral delivery system (pharmaceutical/functional foods), as a preharvest food safety hurdle, to promote the shelf-life of food products and develop novel functional foods or/and for developing health benefits, and therapeutic aims. This review addresses the latest postbiotic applications with regard to pharmaceutical formulations and commercial food-based products. Potential postbiotic applications in the promotion of host health status, prevention of disease, and complementary treatment are also reviewed.

Antibiotic therapy for pan-drug-resistant infections.

Antibiotic resistance occurs when microorganisms resist the drugs used against the infection caused by them and neutralize their effects over time using various mechanisms. These mechanisms include preventing drug absorption, changing drug targets, drug inactivating, and using efflux pumps, which ultimately cause drug resistance, which is named pan-drug-resistant (PDR) infection if it is resistant to all antimicrobial agents. This type of drug resistance causes many problems in society and faces the health system with difficulties; therefore their treatment is crucial and encourages doctors to develop new drugs to treat them. PDR Gram-negative bacteria, including Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae, and Escherichia coli are among the most significant resistant bacteria to many antimicrobial agents, and only a limited range of antibiotics, especially synergistically are effective on them. For the therapy of PDR A. baumannii, tigecycline in combination with colestimethate, imipenem, amikacin, and ampicillin-sulbactam are the most effective treatments. The utilization of ß-lactamase inhibitors such as ceftolozane-tazobactam, ceftazidime-avibactam, or imipenem-cilastatin-relebactam has the most efficacy against PDR P. aeruginosa. The PDR K. pneumoniae has been treated in the last decades with tigecycline and colistin, but currently, nitrofurantoin, fosfomycin, and pivmecillinam seem to be the most effective agent for the therapy of PDR E. coli. While these drugs impressively struggle with PDR pathogens, due to the daily increase in antibiotic resistance in microorganisms worldwide, there is still an urgent need for the expansion of novel medicines and methods of combating resistance.

Postbiotics as the key mediators of the gut microbiota-host interactions.

The priority of the Sustainable Development Goals for 2022 is to reduce all causes related to mortality. In this regard, microbial bioactive compounds with characteristics such as optimal compatibility and close interaction with the host immune system are considered a novel therapeutic approach. The fermentation process is one of the most well-known pathways involved in the natural synthesis of a diverse range of postbiotics. However, some postbiotics are a type of probiotic response behavior to environmental stimuli that usually play well-known biological roles. Also, postbiotics with unique structure and function are key mediators between intestinal microbiota and host cellular processes/metabolic pathways that play a significant role in maintaining homeostasis. By further understanding the nature of parent microbial cells, factors affecting their metabolic pathways, and the development of compatible extraction and identification methods, it is possible to achieve certain formulations of postbiotics with special efficiencies, which in turn will significantly improve the performance of health systems (especially in developing countries) toward a wide range of acute/chronic diseases. The present review aims to describe the fundamental role of postbiotics as the key mediators of the microbiota-host interactions. Besides, it presents the available current evidence regarding the interaction between postbiotics and host cells through potential cell receptors, stimulation/improvement of immune system function, and the enhancement of the composition and function of the human microbiome.

Can food matrices be considered as a potential carrier for COVID-19?

Humanity is currently facing a life-threatening challenge from the infectious and epidemic disease SARS-CoV-2. To date, the various modes of transmission of the virus have not been fully elucidated. In this regard, there is a possibility of transmission of the virus through food products. The COVID-19 pandemic disease, like those associated with SARS and MERS, is transmitted mainly through the respiratory tract and airborne aerosol particles, but the presence of fragments of the genetic virus (RNA) in the feces of numerous patients proposes that their fecal-oral pathway may be expanded. In addition, people with gastrointestinal disorders such as atrophic gastritis and metaplasia may be susceptible to COVID-19 infection. Accordingly, food may act as a potential carrier of COVID-19 due to environmental or cross-contamination. According to the available evidence, the spread and possibility of transmission of COVID-19 contamination from humans to food products are possible. Beyond that, there is some evidence that some food sources of animal origin, such as pigs and rabbits, can be contaminated by COVID-19. Therefore, the transmission of the virus through some meat products may be conceivable. Due to the rapid release rate of COVID-19 and its stability in various milieus, especially food manufacturing circumstances, it may enter the matrix during different stages of traditional or industrial food processing. Therefore, preventive measures are recommended to be utilized in the food manufacturing sector. The present study explored the risk of different food matrices, including dairy products, bread, meat and meat products, vegetables, fruits, and processed foods, as potential carriers for the transmission of COVID-19.

Bacterial Proteomics and its Application in Pathogenesis Studies.

Bacteria build their structures by implementing several macromolecules such as proteins, polysaccharides, phospholipids, and nucleic acids, which preserve their lives and play an essential role in their pathogenesis. There are two genomic and proteomic methods to study various macromolecules of bacteria, which are complementary methods and provide comprehensive information. Proteomic approaches are used to identify proteins and their cell applications. Furthermore, macromolecules are utilized to study bacteria's structures and functions. These proteinbased methods provide comprehensive information about the cells, such as the external structures, internal compositions, post-translational modifications, and mechanisms of particular actions, including biofilm formation, antibiotic resistance, and adaptation to the environment, promoting bacterial pathogenesis. These methods use various devices such as MALDI-TOF MS, LC-MS, and two-dimensional electrophoresis, which are valuable tools for studying different structural and functional proteins of the bacteria and their mechanisms of pathogenesis, causing rapid, easy, and accurate diagnosis of the infections.

Induction of proteome changes involved in biofilm formation of Enterococcus faecalis in response to gentamicin.

BACKGROUND: Enterococcus faecalis is a significant cause of nosocomial infections and other diseases, including endocarditis, bacteremia, and urinary tract infections. This microorganism forms biofilms to overcome difficult environmental conditions, such as lack of oxygen, lack of water, and the presence of antimicrobials. These biofilms make diseases difficult by changing their proteome contents, protecting the bacterium, and increasing their pathogenicity. This study aimed to evaluate gentamicin's effect on proteome changes and biofilm formation in E. faecalis. METHOD: Twenty-five clinical isolates and one standard isolate were selected for the experiments. A label-free/gel-free proteomic and microtiter plate techniques were used to study proteome changes and biofilm formation, respectively. RESULTS: Gentamicin significantly increased the biofilm formation in 62% of isolates and the rest of the isolates; no significant change was observed. The abundance of lactate utilization protein C, ribosomal RNA small subunit methyltransferase H, and protein translocase subunit SecA were increased. However, the abundances of proteins effective in cell division and metabolism, such as replication initiation protein and segregation and condensation protein A, were decreased. CONCLUSION: The present study's findings exhibited that antibiotics might have adverse effects on treatment and increase microorganisms' pathogenicity. It was observed in gentamicin as induction of biofilm formation through different mechanisms, particularly changes in the expression of specific proteins in E. faecalis.

False-Positive Mycobacterium tuberculosis Detection: Ways to Prevent Cross-Contamination.

The gold standard method for diagnosis of tuberculosis is the isolation of Mycobacterium tuberculosis through culture, but there is a probability of cross-contamination in simultaneous cultures of samples causing false-positives. This can result in delayed treatment of the underlying disease and drug side effects. In this paper, we reviewed studies on falsepositive cultures of M. tuberculosis. Rate of occurrence, effective factors, and extent of false-positives were analyzed. Ways to identify and reduce the false-positives and management of them are critical for all laboratories. In most cases, falsepositive is occurring in cases with only one positive culture but negative direct smear. The three most crucial factors in this regard are inappropriate technician function, contamination of reagents, and aerosol production. Thus, to reduce false-positives, good laboratory practice, as well as use of whole-genome sequencing or genotyping of all positive culture samples with a robust, extra pure method and rapid response, are essential for minimizing the rate of false-positives. Indeed, molecular approaches and epidemiological surveillance can provide a valuable tool besides culture to identify possible false positives.

Clinical manifestation, diagnosis, prevention and control of SARS-CoV-2 (COVID-19) during the outbreak period.

The novel coronavirus SARS-CoV-2 (Covid-19), spreading from Wuhan, China, is one of the causes of respiratory infections that can spread to other people through respiratory particles, and can cause symptoms such as fever, dry cough, shortness of breath, anorexia, fatigue and sore throat in infected patients. This review summarizes current strategies on the diagnosis. Additionally, treatments, infection prevention and control of the SARS-CoV-2 are addressed. In addition to the respiratory system, this virus can infect the digestive system, the urinary system and the haematological system, which causes to observe the virus in the stool, urine and blood samples in addition to throat sample. The SARS-CoV-2 causes changes in blood cells and factors and makes lung abnormalities in patients, which can be detected by serological, molecular, and radiological techniques by detecting these changes and injuries. Radiological and serological methods are the most preferred among the other methods and the radiological method is the most preferred one which can diagnose the infection quickly and accurately with fewer false-negatives, that can be effective in protecting the patient's life by initiating treatment and preventing the transmission of infection to other people.

Tuberculosis and Diabetes Mellitus in Northwest of Iran.

BACKGROUND: Planning for control of tuberculosis would need to screen and identify individuals susceptible to TB. Due to the weakness of immune system in diabetic patients, it is more likely for them to reactivate latent TB infection. Regarding the increasing number of diabetics in the community, in this study efforts have been made to estimate the frequency of individuals who have tuberculosis and diabetes mellitus (TB-DM) simultaneously, as it could help making preventive decisions to reduce TB in this part of Iran. MATERIALS AND METHODS: In this study, 329 cases of confirmed TB patients were divided into two groups of diabetic and non-diabetic, then demographic information and clinical variables have been compared between the two groups. RESULTS: Among the examined subjects, 47 patients (14.29 %) had suffered from diabetes mellitus and tuberculosis. All of the DM patients had pulmonary tuberculosis and 87.23% of them were over the age of 50. CONCLUSION: Majority of DM-TB patients were over 50 years of age and also more than half of them were women. So it seems that for DM women over the age of 50, to detect tuberculosis, screening tests such as PPD may be necessary.