Epidemiological characterization of clinical isolates of meticillin resistant Staphylococcus aureus through multilocus sequence typing and staphylococcal cassette chromosome mec typing in Northwest Iran.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA), is considered a potential and aggressive nosocomial pathogen. It accounts for 50% of S. aureus isolates in tertiary hospitals in Iran, however, there is no sufficient evolutionary and epidemiological investigation about this medically important bacterium. We aimed to study the lineage and evolution of MRSA in Northwest Iran during 2021-2022 based on the obtained phenotypic and genotypic characteristics. MATERIALS AND METHODS: Seventy-two non-duplicate MRSA isolates were collected from 3 referral hospitals in Tabriz, Ardebil, and Urmia cities. The antimicrobial susceptibility patterns were determined by disk diffusion test and micro broth dilution methods. Thereafter 4 virulence genes (eta, etb, pvl, tst) and 5 types of staphylococcal cassette chromosome mec (SCCmec) were detected by PCR. In the final step, representative isolates were selected to be studied by Multilocus sequence typing (MLST). RESULTS: The highest resistance was observed to erythromycin and clindamycin at a rate of 76.4%, followed by ciprofloxacin (61.1%), gentamicin (54.2%), rifampin (38.9%), and co-trimoxazole (27.8%). All isolates were susceptible to vancomycin. The virulence genes of etb, pvl, tst, and eta were detected in 50%, 29.2%, 21.8%, and 13.9% of isolates, respectively. SCCmec types III and I were the most prevalent types, followed by types IV, II, and V. MLST analysis revealed 6 sequence types: ST6854, ST5282, ST127, ST7804, ST1607, and ST7784. Two MLST-based clonal complexes (CC8, and CC97) were identified as well. CONCLUSION: The ST numbers were non-repetitive. CC8 as a pandemic clone and an individual lineage and clinically significant clade was reported as the most prevalent clonal complex. It is essential periodic evaluations of antibiotic susceptibility patterns and study the evolutionary characteristics of medical-challenging microorganisms in particular MRSA to effectively treat and restrict the outbreaks.

Gut microbiota and obesity: an overview of microbiota to microbial-based therapies.

The increasing prevalence of obesity and overweight is a significant public concern throughout the world. Obesity is a complex disorder involving an excessive amount of body fat. It is not just a cosmetic concern. It is a medical challenge that increases the risk of other diseases and health circumstances, such as diabetes, heart disease, high blood pressure and certain cancers. Environmental and genetic factors are involved in obesity as a significant metabolic disorder along with diabetes. Gut microbiota (GM) has a high potential for energy harvesting from the diet. In the current review, we aim to consider the role of GM, gut dysbiosis and significant therapies to treat obesity. Dietary modifications, probiotics, prebiotics, synbiotics compounds, using faecal microbiota transplant, and other microbial-based therapies are the strategies to intervene in obesity reducing improvement. Each of these factors serves through various mechanisms including a variety of receptors and compounds to control body weight. Trial and animal investigations have indicated that GM can affect both sides of the energy-balancing equation; first, as an influencing factor for energy utilisation from the diet and also as an influencing factor that regulates the host genes and energy storage and expenditure. All the investigated articles declare the clear and inevitable role of GM in obesity. Overall, obesity and obesity-relevant metabolic disorders are characterised by specific modifications in the human microbiota's composition and functions. The emerging therapeutic methods display positive and promising effects; however, further research must be done to update and complete existing knowledge.

The critical role of Faecalibacterium prausnitzii in human health: An overview.

Faecalibacterium prausnitzii (F. prausnitzii) is one of the most abundant bacterial species in the colon of healthy human adults and representing more than 5% of the total bacterial population. Recently, it has been known as a major actor in human intestinal health and a biosensor. Changes in this species population richness and quantity have been observed in many illnesses and several investigations have reported that abundance of F. prausnitzii is reduced in different intestinal disorders. In the current review, we aim to consider literature from various library databases and electronic searches (Science Direct, PubMed, and Google Scholar) which were randomly collected and serve as an overview of different features of F. prausnitzii including metabolites, anti-inflammatory action, and correlation of dysbiosis of this bacterium with various complications in human.

Non-alcoholic fatty liver diseases: from role of gut microbiota to microbial-based therapies.

Non-alcoholic fatty liver disease (NAFLD) is the well-known disease of the liver in adults and children throughout the world. The main manifestations related to NAFLD are an unusual storage of lipid in hepatocytes (hepatic steatosis) and progression of inflammation for non-alcoholic steatohepatitis (NASH). NAFLD is described as a multifactorial complication due to the genetic predisposition, metabolic functions, inflammatory, gut microbiota (GM), and environmental factors. The GM dysregulation among these factors is correlated to NAFLD development. In recent decades, advanced microbial profiling methods are continuing to shed light on the nature of the changes in the GM caused by NASH and NAFLD. In the current review, we aim to perform a literature review in different library databases and electronic searches (Science Direct, PubMed, and Google Scholar) which were randomly obtained. This will be done in order to provide an overview of the relation between GM and NAFLD, and the role of prebiotics, probiotics, and fecal microbiota transplantation (FMT), as potential therapeutic challenges for NAFLD.

The role of Staphylococcus aureus in cystic fibrosis pathogenesis and clinico-microbiological interactions.

Cystic fibrosis (CF) is a progressive and inherited disease that affects approximately 70000 individuals all over the world annually. A mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene serves as its defining feature. Bacterial infections have a significant impact on the occurrence and development of CF. In this manuscript, we discuss the role and virulence factors of Staphylococcus aureus as an important human pathogen with the ability to induce respiratory tract infections. Recent studies have reported S. aureus as the first isolated bacteria in CF patients. Methicillin-resistant Staphylococcus aureus (MRSA) pathogens are approximately resistant to all ß-lactams. CF patients are colonized by MRSA expressing various virulence factors including toxins, and Staphylococcal Cassette Chromosome mec (SCCmec) types, and have the potential for biofilm formation. Therefore, variations in clinical outcomes will be manifested. SCCmec type II has been reported in CF patients more than in other SCCmec types from different countries. The small-colony variants (SCVs) as specific morphologic subtypes of S. aureus with slow growth and unusual properties can also contribute to persistent and difficult-to-treat infections in CF patients. The pathophysiology of SCVs is complicated and not fully understood. Patients with cystic fibrosis should be aware of the intrinsic risk factors for complex S. aureus infections, including recurring infections, physiological issues, or coinfection with P. aeruginosa.

Severe acute respiratory syndrome coronavirus 2 infection: Role of interleukin-6 and the inflammatory cascade.

Since December 2019, a novel coronavirus that represents a serious threat to human lives has emerged. There is still no definite treatment for severe cases of the disease caused by this virus, named coronavirus disease 2019 (COVID-19). One of the most considered treatment strategies targets the exaggerated immune regulator, and interleukin (IL)-6 is a crucial pro-inflammatory mediator. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cases show an elevated level of IL-6 related to disease severity. IL-6 activity can be inhibited by the following: IL-6 itself, IL-6 signaling pathways such as Janus kinase and signal transducer and activator of transcription (JAK-STAT), gp130, IL-6R, and downstream activated ILs, such as IL-17 and IL-6 cytokine. Currently, according to these studies and their results, IL-6 blockade with anti-IL-6 or its receptor antibodies such as tocilizumab in COVID-19 is beneficial in severe cases and may reduce the mortality rate. JAK-STAT inhibitors block the cytokine storm by inhibiting several crucial pro-inflammatory mediators such as TNF-α and IL-6 and have shown various results in clinical trials. IL-6 induces IL-17 secretion, and IL-17 is involved in the pathogenesis of inflammatory processes. Clinical trials of anti-IL-17 drugs are currently recruiting, and anti-gp130 antibody is preclinical. However, this agent has shown positive effects in inflammatory bowel disease clinical trials and could be tested for SARS-CoV-2. This study aimed to review the role of IL-6 in the cytokine storm and studies regarding IL-6 and blockade of its inflammatory pathways in COVID-19 to determine if any of these agents are beneficial for COVID-19 patients.

Extrapulmonary Clinical Manifestations in COVID-19 Patients.

COVID-19 manifestations in symptomatic patients can be in the form of pneumonia, acute respiratory syndrome, and multiple organ dysfunction as well. Renal complications, gastrointestinal dysfunctions, endocrine system disorders, myocardial dysfunction and arrhythmia, neurological dysfunctions, dermatological symptoms, hematological manifestations, and thromboinflammation are among the reported extrapulmonary complications. Moreover, the presence of coagulopathy, excessive and dysregulated immune responses, and autoimmunity by COVID-19 patients is considerable. The pathogenesis of infection entails the entry of the virus via receptors on cells, principally angiotensin-converting enzyme 2 receptors. Direct virus damage coupled with indirect effects of viral infection including thromboinflammation, dysfunction of the immune system, and dysregulation of the renin-angiotensin system leads to multiple organ failure. This review outlines the extrapulmonary organ-specific complications and their pathophysiology and epidemiology.

Poly (ε-Caprolactone)/Cellulose Nanofiber Blend Nanocomposites Containing ZrO2 Nanoparticles: A New Biocompatible Wound Dressing Bandage with Antimicrobial Activity.

Purpose: In the present study, the poly (ε-caprolactone)/cellulose nanofiber containing ZrO2 nanoparticles (PCL/CNF/ZrO2 ) nanocomposite was synthesized for wound dressing bandage with antimicrobial activity. Methods: PCL/CNF/ZrO2 nanocomposite was synthesized in three different zirconium dioxide amount (0.5, 1, 2%). Also the prepared nanocomposites were characterized by Infrared spectroscopy (FT-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). In addition, the morphology of the samples was observed by scanning electron microscopy (SEM). Results: Analysis of the XRD spectra showed a preserved structure for PCL semi-crystalline in nanocomposites and an increase in the concentrations of ZrO2 nanoparticles, the structure of nanocomposite was amorphous as well. The results of TGA, DTA, DSC showed thermal stability and strength properties for the nanocomposites which were more thermal stable and thermal integrate compared to PCL. The contact angles of the nanocomposites narrowed as the amount of ZrO2 in the structure increased. The evaluation of biological activities showed that the PCL/CNF/ZrO2 nanocomposite with various concentrations of ZrO2 nanoparticles exhibited moderate to good antimicrobial activity against all tested bacterial and fungal strains. Furthermore, cytocompatibility of the scaffolds was assessed by MTT assay and cell viability studies proved the non-toxic nature of the nanocomposites. Conclusion: The results show that the biodegradability of nanocomposite has advantages that can be used as wound dressing.

Carbohydrate polymer-based silver nanocomposites: Recent progress in the antimicrobial wound dressings.

Wound healing is a dynamic and complex process which affects the quality of life in patients and annually causes high costs for the health system, worldwide. Polymers from natural origins such as polysaccharides have gained particular interest between researchers for wound dressing applications due to their abundance in nature, biocompatibility with human tissues, and ideal physicochemical properties. Aside from their supportive effect in wound care, polysaccharides and their derivatives can actively contribute to the healing process. Silver nanoparticles are widely used noble metal nanoparticles incorporated in wound dressings due to their low toxicity for human cells, naturally availability, and strong antimicrobial effects. In the present study, we will review the most frequently used polysaccharides in wound dressing procedure with silver or silver nanoparticles accommodated. The methods of synthesis, physicochemical properties, healing efficiencies, toxicity against human tissues, antibacterial and antifungal effects of each material will also be discussed.