Proteomics Exploration of Brucella melitensis to Design an Innovative Multi-Epitope mRNA Vaccine.

Brucellosis is a chronic and debilitating disease in humans, causing great economic losses in the livestock industry. Making an effective vaccine is one of the most important concerns for this disease. The new mRNA vaccine technology due to its accuracy and high efficiency has given promising results in various diseases. The objective of this research was to create a novel mRNA vaccine with multiple epitopes targeting Brucella melitensis. Seventeen antigenic proteins and their appropriate epitopes were selected with immunoinformatic tools and surveyed in terms of toxicity, allergenicity, and homology. Then, their presentation and identification by MHC cells and other immune cells were checked with valid tools such as molecular docking, and a multi-epitope protein was modeled, and after optimization, mRNA was analyzed in terms of structure and stability. Ultimately, the immune system's reaction to this novel vaccine was evaluated and the results disclosed that the designed mRNA construct can be an effective and promising vaccine that requires laboratory and clinical trials.

The Effects of Probiotics, Prebiotics, and Synbiotics on Wound Infection: A Systematic Review.

INTRODUCTION: This systematic review aimed to summarize the currently available evidence on the effect of oral probiotic therapy on infected wound healing among patients who underwent surgery. MATERIALS AND METHODS: An electronic search was conducted for articles published during 2010- 2022 in Embase, PubMed/Medline, Scopus, Web of Science, and Google Scholar using the keywords "probiotics," "prebiotics," "synbiotics," and "wound infection." The titles and abstracts of 2625 articles were screened, and 22 publications that fulfilled the inclusion criteria were included. RESULTS: The current review provides evidence of the beneficial effects of probiotics on wound infection, significantly reducing the duration of antibiotic usage and the length of hospital stay for patients, with no serious side effects reported. Wound infections following various surgeries, such as abdominal wound surgery, colorectal cancer resection, periampullary neoplasms treatment, liver and bile duct resection, pancreaticoduodenectomy, esophagostomy, dental wound surgery, plastic surgery, and burns, are shown to be positively affected by probiotic usage. Although, in some cases, the improvements were not statistically significant, overall, the administration of probiotics appears to be satisfactory in this regard. CONCLUSION: Probiotics demonstrate the ability to prevent the growth of pathogens and maintain wound space sterility by recruiting M2 macrophages, which produce anti-inflammatory markers and enhance the activity of phagocytic cells. Additionally, probiotics can reduce bacterial translocation from their niche to other areas and inhibit the production of bacterial mediators that lead to bacterial invasion.

Effectiveness of photodynamic therapy on the treatment of chronic periodontitis: a systematic review during 2008-2023.

Objective: This study investigated the effect of photodynamic therapy on chronic periodontitis patients and then evaluated the microbial, immunological, periodontal, and clinical outcomes. The significant effects of photodynamic therapy obtained by in vitro and in vivo studies have made it a popular treatment for periodontal diseases in recent years. Photodynamic therapy is a novel bactericidal strategy that is stronger, faster, and less expensive than scaling and root planing. Method: This study registered on PROSPERO (CRD42021267008) and retrieved fifty-three randomized controlled trials by searching nine databases (Medline, Embase, Scopus, Open Gray, Google Scholar, ProQuest, the Cochrane Library, Web of Science, and ClinicalTrials.gov) from 2008 to 2023. Of 721 records identified through database searches following title and full-text analysis, and excluding duplicate and irrelevant publications, 53 articles were included in this systematic review. Fifty of the 53 eligible studies fulfilled all the criteria in the Joanna Briggs Institute's (JBI's) Checklist for RCTs; the remaining articles met 9-12 criteria and were considered high quality. Results: The present study showed that photodynamic therapy in adjunct to scaling and root planing has the potential to improve periodontal parameters such as clinical attachment loss or gain, decrease in bleeding on probing, and probing pocket depth. In addition, photodynamic therapy decreases the rate of periodontal pathogens and inflammation markers, which, in turn, reduces the progression of periodontitis. Conclusion: Photodynamic therapy is considered a promising, adjunctive, and low-cost therapeutic method that is effective in tissue repair, reducing chronic periodontitis, reducing inflammation, and well-tolerated by patients.

Epidemiology of first- and second-line drugs-resistant pulmonary tuberculosis in Iran: Systematic review and meta-analysis.

Drug resistance among Mycobacterium tuberculosis (MTB) strains is a growing concern in developing countries. We conducted a comprehensive search for relevant studies in Iran on PubMed, Scopus, and Embase until June 12, 2020. Our study focused on determining the prevalence of antibiotic resistance in MTB isolates, with subgroup analyses based on year, location, and drug susceptibility testing (DST) methods. Statistical analyses were performed using STATA software. Our meta-analysis included a total of 47 articles. Among new TB cases, we found the following prevalence rates: Any-resistance to first-line drugs: 31 % (95 % CI, 24-38), mono-drug resistance: 15 % (95 % CI, 10-22), and multidrug resistance to first-line drugs: 6 % (95 % CI, 4-8). There was a significant variation in the rate of MDR among new TB cases based on the year of publication, location, and DST methods (P < 0.0001). We observed substantial variability in multidrug-resistant TB rates among new cases across the studies. Stratified analyses revealed that publication years and DST methods significantly affected resistance rates. Studies from southern and central Iran reported higher any-drug resistance rates, suggesting regional differences. Among retreatment cases, the prevalence rates were as follows: Any resistance: 68 % (95 % CI 58-78), mono-resistance: 19 % (95 % CI 7-34), multidrug resistance: 28 % (95 % CI 15-43). Our study revealed that the prevalence of drug-resistant TB (DR-TB) among TB cases in Iran is higher than the global average. Particularly, MDR-TB among retreatment TB cases is a significant public health issue.

Prevalence of linezolid resistance in Streptococcus pneumoniae isolates: a systematic review and meta-analysis.

Aim: This study aimed to understand the current level of linezolid (LNZ) resistance in Streptococcus pneumoniae isolates reported over the past 10 years. Material & methods: An electronic search was conducted for the following keywords: ((Streptococcus pneumoniae [title/abstract]) OR (Pneumococcus [title/abstract]) OR (Pneumococci [title/abstract]) AND (linezolid [title/abstract]) OR (Zyvox [title/abstract])) OR (Zyvoxid [title/abstract])). Result: Out of all the studies, 80 had a cross-sectional design, while 11 followed a cohort approach. The prevalence of LNZ resistance among S. pneumoniae isolates ranged from 0% to 4.86%. Discussion: Urgent, high-powered, randomized, controlled trials with participants from endemic regions are needed to gain a comprehensive understanding of the impact on and significance of LNZ treatment to patients.

The effects of Fasciola hepatica recombinant proteins (peroxiredoxin and cathepsin L1) on Crohn's disease experimental model.

The immunomodulatory potential of the excretory-secretory (E/S) proteins of the helminths has been shown in previous investigations. This study evaluated the effects of the recombinants and excretory-secretory proteins of the Fasciola hepatica on induced colitis in Balb/c mice. The F. hepatica Recombinant proteins, Cathepsin L1 and Peroxiredoxin, and E/S proteins were intraperitoneally injected into the three mice groups as the case groups, while the control groups received PBS. Colitis was induced in mice by intraluminal administration of the 2, 4, 6-Trinitrobenzenesulfonic acid solution (TNBS). After 8 h, the case groups received the second dosage of the treatments, and it was repeated 24 h later. The immunological, pathological, and macroscopic changes were evaluated 3 days after colitis induction. The macroscopic evaluation revealed significantly lower inflammatory scores in the mice treated with recombinant Peroxiredoxin (rPRX) and recombinant Cathepsin L1 (rCL1). Despite the macroscopic observation, the pathological finding was insignificant between the groups. IFN-γ secretion was significantly lower in splenocytes of the groups that received rPRX, rCL1, and E/S than the controls. IL-10 showed significantly higher levels in groups treated with rPRX and rCL1 than controls, whereas the level of IL-4 was not statistically significant. Excretory-secretory proteins of the F. hepatica showed immunomodulatory potency and the main effects observed in this study were through the reduction of inflammatory cytokine and inflammation manifestation as well as induction of anti-inflammatory cytokines.

Novel toxin-based mRNA vaccine against Clostridium perfringens using in silico approaches.

Clostridium perfringens is a bacterium that causes gastrointestinal diseases in humans and animals. The several powerful toxins such as alpha toxin (CPA), beta toxin (CPB), enterotoxin (CPE), Epsilon toxin (ETX), and theta toxin, play a major role in its pathogenesis. Traditional vaccine development methods are time-consuming and costly. In silico approaches offer an alternative strategy for designing vaccines by analyzing biological data and predicting immunogenic peptides. In this study, computational tools were utilized to design a RNA vaccine targeting C. perfringens toxins. Toxin protein sequences were retrieved and their linear B-cell, MHCI, and MHCII binding epitopes were predicted. Allergenicity, toxigenicity, and IFN-γ induction were assessed to select non-allergenic, non-toxic, and IFN-γ-inducing epitopes. Molecular docking was performed to identify epitopes that fit within the binding cleft of MHC alleles. A final peptide vaccine construct was designed with selected epitopes separated by a linker sequence. The antigenicity and physicochemical properties of the vaccine were evaluated. Immune response simulation showed enhanced secondary and tertiary immune responses, increased levels of immunoglobulins, cytotoxic T lymphocytes, helper T lymphocytes, macrophage activity, and elevated levels IFN-γ and interleukin-2. Docking analysis was done to assess interactions between the vaccine structure and Toll-like receptors. Codon optimization was performed, and a final RNA vaccine construct was designed. The secondary structure of the RNA vaccine was predicted and validated. Overall, this study demonstrates the potential of in silico approaches for designing an RNA vaccine against C. perfringens toxins, contributing to improved prevention and control of associated diseases.

Evaluation of Genetic Content of the CRISPR Locus in Listeria monocytogenes Isolated From Clinical, Food, Seafood and Animal Samples in Iran.

CRISPR arrays, which are organized to fight against non-self DNA elements, have shown sequence diversity that could be useful in evolution and typing studies. In this study, 55 samples of L. monocytogenes isolated from different sources were evaluated for CRISPR sequence polymorphism. The CRISPR loci were identified using CRISPR databases. A single PCR assay was designed to amplify the target CRISPRs using an appropriate universal primer. Sequencing results were analyzed using CRISPR databases and BLASTn, and the CRISPR locus was present in all the strains. Three hundred repeats including 55 terminal repeats were identified. Four types of consensuses direct repeat (DR) with different lengths and sequences were characterized. Sixty repeat variants were observed which possessed different polymorphisms. Two hundred and fifty spacers were identified from which 35 consensus sequences were determined, indicating the high polymorphism of the CRISPR spacers. The identified spacers showed similarities to listeria phage sequences, other bacterial phage sequences, plasmid sequences and bacterial sequences. In order to control the bacterial outbreaks, a robust and precise system of subtyping is required. High levels of polymorphism in the CRISPR loci in this study might be related to the origin and time of the samples' isolation. However, it is essential to assess, on a case-by-case basis, the characteristics of any given CRISPR locus before its use as an epidemiological marker. In conclusion, the results of this study showed that the use of sequence content of CRISPR area could provide new and valuable information on the evolution and typing of the L. monocytogenes bacterium.

Clinical efficacy of probiotics in prevention of infectious diseases among hospitalized patients in ICU and non-ICU wards in clinical randomized trials: A systematic review.

Background and Aims: The present study aimed to review probiotics' clinical efficacy in preventing infectious diseases among hospitalized patients in ICU and non-ICU wards. Methods: A search of Medline, EMBASE, The Cochrane Library, Science Direct, Open Grey, and Google Scholar was conducted for eligible publications from 2002 to 2020 following the requirements outlined in the PRISMA guideline. The search strategy was based on the combination of the following terms: "probiotics," "prebiotics," "synbiotics," and "cross-infection." The logical operators "AND" (or the equivalent operator for the databases) and "OR" (e.g., probiotics OR prebiotics OR synbiotics) were used. Results: The results indicated that the probiotic consumption caused a significant reduction in antibiotic-associated diarrhea (AAD) and Clostridioides difficile infection (CDI) in 2/8 randomized clinical trials (RCTs) investigating AAD/CDI. Also, 5/12 clinical trials highlighted the considerable effects of probiotics on the reduction or prevention of ventilator associated pneumoniae (VAP), so the mean prevalence of VAP was lower in the probiotic group than in the placebo group. The total rate of nosocomial infections among preterm infants was nonsignificantly higher in the probiotic group compared to the control group. Conclusion: This systematic review shows that the administration of probiotics has moderate preventive or mitigating effects on the occurrence of VAP in ICU patients, CDI, AAD, and nosocomial infections among children. Consequently, applying antibiotics along with the proper probiotic species can be advantageous.

Worldwide Prevalence of Colistin Resistance among Enterobacteriaceae: a Systematic Review and Meta-Analysis.

BACKGROUND: The aim of the present meta-analysis is to estimate the prevalence of colistin resistance among the Enterobacteriaceae family. METHODS: Articles from various databases (Medline, Scopus, Web of Science, and Embase) examining colistin resistance among Enterobacteriaceae in human, animal, and environmental specimens were searched from 2016 to 2021 using related keywords. The Cochran's Q-test and I2 were applied to evaluate heterogeneity and a random-effects model was used to assess the pooled prevalence. The meta-regression method was applied to determine heterogeneity among the studies. RESULTS: Of 5,145 articles, 60 articles with a sample size of 404,856 was included. The pooled estimate for prevalence of bacterial resistance were 9.13% (95% CI: 6.96 to 11.56; I-squared = 99.4%) in total, 8.34% (95% CI: 5.87 to 11.16; I-squared = 99.3%) for Klebsiella spp. subgroup and 3.44% (95% CI: 2.46 to 4.57; I-squared = 98.4%) for E. coli subgroup. The pooled prevalence for human and animal settings were 9.07% (95% CI: 6.77 to 11.67; I-squared = 99.3%) and 9.73% (95% CI: 484 to 16.02; I-squared = 99.4%), respectively. The continent (coefficient: 3.51; 95% CI: 0.08 to 6.94, p: 0.045) and bacterial type (coefficient: 0.03; 95% CI: 0.01 to 0.05 p: 0.042) had significant effects on heterogeneity among studies. CONCLUSION: The results of this study showed that the prevalence of colistin resistance in Enterobacteriaceae was similar between animals and humans, with the highest colistin resistance found in Klebsiella strains.

Clinical Efficacy of Probiotics on Oral Health: A Systematic Review of Clinical Trials.

INTRODUCTION: Periodontal diseases and dental caries are the two most common dental diseases caused by the dental plaque. OBJECTIVE: The aim of the present study was to review the clinical efficacy of probiotics for oral health in randomized controlled trials. METHODS: An electronic search was conducted in December 2021 in Embase, Medline, The Cochrane Library, ProQuest, and Google Scholar using the following keywords: "mouthwash" and "probiotics". The titles and abstracts of 3,775 articles were screened and 24 publications that fulfilled the inclusion criteria were included. RESULTS: A total of 24 clinical trials were reviewed, including 1612 participants receiving either probiotics or mouth treatments. The results of this review indicated that individuals receiving probiotic products have a significant reduction (65% reduction; p < 0.05) in the count of Streptococcus mutants in their mouths. It was also found that probiotic products were more effective or equal in effect compared to chlorhexidine in reducing oral pathogens, gingival index, and plaque index scores. On the other hand, the consumption of xylitol mouthwash was shown to cause an improvement in salivary parameters. Considering their safety and effectiveness, the use of probiotic products, such as kefir and mouthwashes, has been recommended against cariogenic bacteria and periodontal diseases. CONCLUSION: Probiotics are considered a safe alternative to conventional therapies, such as chlorhexidine and fluoride. Co-administration of chlorhexidine, fluoride, and probiotics seems to be a perfect package.

In silico Study of the Proteins Involved in the Persistence of Brucella spp.

BACKGROUND: One of the major problems with Brucella infections is its tendency to become chronic and recurrent, providing a hindrance to the management of this infection. It has been proposed that chronicity is greatly affected by a phenomenon called persistence in bacteria. Several mechanisms are involved in bacterial persistence, including the type II toxin-antitoxin system, the SOS and oxidative and stringent responses. METHODS: In this in silico study, these persistence mechanisms in Brucella spp. were investigated. RESULTS: The structure and the interactions between modules involved in these systems were designed, and novel peptides that can interfere with some of these important mechanisms were developed. CONCLUSION: Since peptide-based therapeutics are a new and evolving field due to their ease of production, we hope that peptides developed in this study, as well as the information about the structure and interactions of modules of persistence mechanisms, can further be used to design drugs against Brucella persister cells in the hope of restraining the chronic nature of Brucellosis.

Development of innovative multi-epitope mRNA vaccine against Pseudomonas aeruginosa using in silico approaches.

The rising issue of antibiotic resistance has made treating Pseudomonas aeruginosa infections increasingly challenging. Therefore, vaccines have emerged as a viable alternative to antibiotics for preventing P. aeruginosa infections in susceptible individuals. With its superior accuracy, high efficiency in stimulating cellular and humoral immune responses, and low cost, mRNA vaccine technology is quickly replacing traditional methods. This study aimed to design a novel mRNA vaccine by using in silico approaches against P. aeruginosa. The research team identified five surface and antigenic proteins and selected their appropriate epitopes with immunoinformatic tools. These epitopes were then examined for toxicity, allergenicity and homology. The researchers also checked their presentation and identification by major histocompatibility complex cells and other immune cells through valuable tools like molecular docking. They subsequently modeled a multi-epitope protein and optimized it. The mRNA was analyzed in terms of structure and stability, after which the immune system's response against the new vaccine was simulated. The results indicated that the designed mRNA construct could be an effective and promising vaccine that requires laboratory and clinical trials.

Brain Abscess Caused by Nocardia asteroides in a Diabetic Patient: A Rare Case Report.

Nocardial brain abscess is usually associated with immunodeficiency, but can sometimes emerge in healthy individuals. This infection can be acquired through inhalation or direct inoculation of the bacteria, followed by dissemination to various organs, including the brain, through blood circulation. Mortality rate due to nocardial cerebral abscess is three times higher than that associated with cerebral abscess caused by other types of bacteria. Moreover, patients with Nocardia asteroides-associated brain abscess show poorer prognosis compared to patients with brain abscess caused by other Nocardia species, which is probably due to the high tendency of N. asteroides to become resistant to numerous antibiotics. It is, therefore, of paramount importance to diagnose and treat N. asteroides cerebral abscess in patients as soon as possible. The current paper is a rare report of a brain abscess caused by N. asteroides in a diabetic patient who failed to respond to multiple antibiotics (trimethoprim/sulfamethoxazole and amikacin), but improved by receiving imipenem and linezolid, and was finally successfully treated by surgical operation and long-term antibiotic therapy (imipenem and linezolid).

The Influence of Probiotics Consumption on Management of Prediabetic State: A Systematic Review of Clinical Trials.

Prediabetes consists of the intermediary stage between normal glucose regulation and overt diabetes mellitus and develops when blood glucose levels are higher than normal but not high enough to confirm a type 2 diabetes mellitus diagnosis (T2DM). Recent evidence suggests that probiotics could be promising approaches to improve this state. In this study, we performed a systematic review to compile the results of clinical trials investigating the effects of pro-/pre-/synbiotics on prediabetes subjects from 2010 to 2020. The article search was carried out in Medline, Embase, Scopus, Web of Science, The Cochrane Library, Clinical trials.gov, ProQuest, Open Grey, and Google Scholar. Search filters were developed using 2 parameters: "prestate diabetes" and "probiotics." Of the 418 studies that were screened, 15 original articles reached the inclusion criteria. Pooling data from these trials showed positive and significant effects of probiotics in the reduction of hyperglycemia, insulin concentration levels, lipid profile, and BMI (Body mass index). Administration of probiotics may provide beneficial and healthful effects in the clinical management of patients with prediabetes and metabolic syndrome. Different probiotics compositions have shown beneficial and noticeable effects on glucose homeostasis, lipid profiles, BMI, and inflammatory markers in subjects with prediabetes, metabolic syndrome, and healthy individuals and could be advantageous in recomposing the gut microbiota back into the normal state during the prediabetic state.

In Vitro and In Silico Investigation of some Type II TA Genes in H. Pylori.

BACKGROUND: In addition to antibiotic resistance, the entry of Helicobacter pylori into the persistence phase leads to recurrent and chronic infections, as well as the development of antibiotic resistance in persister cells. METHODS: In this study, after genetic confirmation of H. pylori in 20 biopsy specimens, the prevalence of the type II TA systems mazEF, relEB, yafQ/dinJ was investigated. Also, the most common system observed in the study in terms of structure, evolution, and molecular interaction was evaluated by bioinformatics tools. RESULTS: The results of the PCR test on 20 biopsy samples were positive for ureA and glmM genes. Moreover, yafQ/ dinJ was the only module positive in half of the samples (10 samples) in the PCR technique. The toxin residues and their interactions with the cognate antitoxin residues are revealed by docking analysis results. Furthermore, the multiple sequence alignment (MSA) of the YafQ toxin showed that this toxin has a low polymorphism among H. pylori species. The evolutionary study showed that the yafQ toxin had the highest sequence similarity among the bacteria Helicobacter cetorm (60% similarity) and Muricauda olearia (57.35 % similarity). CONCLUSIONS: Collectively, the data of the present study indicate that the YafQ/DinJ is the dominant type II TA system and has the highest frequency among the studied systems in H. pylori, and further studies are required to elucidate its exact role in this bacterium.

Inhibitory Effects of Carvacrol on Biofilm Formation and Expression of Biofilm Related Genes in Clinical Isolates of Enterococcus faecalis.

BACKGROUND: Nowadays, novel antimicrobial strategies are being developed which focus on debilitating, rather than killing the microorganisms. In this regard, anti-biofilm therapy is one of the important ways to combat bacterial infections. Therefore, the aim of the current study was to evaluate the anti-biofilm activity of Carvacrol against E. faecalis by means of its effects on biofilm formation as well as on the gene expression levels of the two biofilm related genes, Epa and Esp. METHODS: A total of 40 clinical strains of E. faecalis were collected from three hospitals in Tehran, Iran during 2020. These isolates were confirmed by biochemical and genotypic methods. Antibacterial and anti-biofilm activity of Carvacrol essence were determined according the standard protocol. Finally, expression level of the biofilm related genes (Epa and Esp) were evaluated before and after the treatment with Carvacrol. RESULTS: A total of 14 isolates were considered as strong biofilm producers and were used for analysis. Carvacrol essence showed the best antibacterial activity at 2,500 µg/mL concentration against all the isolates, the biofilm formation capacity was decreased by Carvacrol essence, and it was statistically significant (p < 0.05). Expression levels of the Esp gene were decreased in 5 isolates while increased in 3 isolates following the Carvacrol treatment. Ex-pression levels of the EpaI gene was significantly decreased (p < 0.05) in 4 isolates following the Carvacrol treatment. CONCLUSIONS: In conclusion, the results presented in this study suggest that carvacrol extract exhibits significant antimicrobial and anti-biofilm properties against E. faecalis, even against vancomycin resistant isolates.

Effects of Pro/Prebiotics Alone over Pro/Prebiotics Combined with Conventional Antibiotic Therapy to Treat Bacterial Vaginosis: A Systematic Review.

Background: Bacterial vaginosis (BV), caused by an imbalance in the vaginal microbiota, can be treated and prevented by probiotics. Pregnant women with BV can experience premature labor and spontaneous abortions. Probiotics and prebiotics promote the proliferation of beneficial microorganisms, alter the composition of the vaginal microbiota, and prevent intravaginal infections in postmenopausal women. In addition to reducing infection symptoms, pre/probiotics can also help prevent vaginal infections. Materials and Methods: A systematic review was conducted on studies from 2010 to 2020 to determine the efficacy of pre/probiotics on the treatment of BV in pregnant and nonpregnant women. The databases Medline, Scopus, Embase, and Google Scholar were systematically searched using the following keywords: "bacterial vaginosis," "probiotics," "prebiotics," and "synbiotics." Results: A total of 1,871 articles were found in the initial search, and 24 clinical trials were considered eligible. In studies comparing the effects of pre/probiotics and placebos with or without antibiotic therapy in patients with BV, significant differences in clinical outcomes were observed. Probiotics reduced the levels of IL-1ß and IL-6, as well as the overall Nugent score and Amsel's criteria for restitution of a balanced vaginal microbiota. In addition, probiotics can reduce the vaginal colonization of Group B streptococci among pregnant women. In subjects treated with probiotics, BV cure rates were higher than those in subjects treated with antibiotics. There were no additional adverse events. Conclusion: Pre/probiotic regimens, when used for BV treatment, are usually safe and can exhibit long-term and short-term benefits. In order to prove the benefits of pre/probiotics in BV treatment, additional high-quality research is required.

Effect of Chlorhexidine (CHX) and Hydrogen Peroxide (H2O2) on the Biofilm Formation of Enterococcus faecalis.

BACKGROUND: Biofilm makes bacteria resistant to antimicrobial agents and facilitates the transmission of infectious diseases in hospitals. Disinfectant compounds are frequently used to control surface contamination. This study was designed to investigate the effect of chlorhexidine (CHX) and hydrogen peroxide (H2O2) on biofilm formation of Enterococcus faecalis. METHODS: This study was performed on 40 E. faecalis clinical isolates. After the determination of MIC, the effect of different concentrations of CHX and H2O2 on the biofilm formation was evaluated. Also, the relative expression level of the studied biofilm genes, following exposure to sublethal concentration of CHX and H2O2, was assessed using quantitative reverse transcription PCR (qRT-PCR). RESULTS: The frequency of the asa1, efaA, epaI, and esp biofilm genes were 80%, 92.5%, 100%, and 75%, respectively. Various concentrations of CHX increased the biofilm mass in E. faecalis. Also, the combination of CHX and H2O2 at sub-minimal inhibitory concentrations, significantly elevated the expression of asa1, epaI, and esp genes. CONCLUSIONS: The results of this study showed that the improper use of disinfectants can increase the ability of biofilm formation in E. faecalis and may cause selective pressure leading to the emergence of biocide-resistant microorganisms.

The effect of probiotics on gestational diabetes and its complications in pregnant mother and newborn: A systematic review and meta-analysis during 2010-2020.

This study was aimed to evaluate the effect of probiotics consumption on gestational diabetes (GD) and its complications in pregnant mother and newborn. The study was registered on PROSPERO (CRD42021243409) and all the enrolled articles were collected from four databases (Medline, Scopus, Embase, and Google Scholar) as randomized controlled trials (RCTs) from 2010 to 2020. A total of 4865 study participants from 28 selected studies were included in this review. The present meta-analysis showed that the consumption of probiotics supplementation has the potential to decrease GD-predisposing metabolic parameters such as blood glucose level, lipid profile, inflammation, and oxidative markers which may reduce GD occurrence among pregnant women.