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Objective: This study aimed to identify glycopeptide resistance genes and virulence factors in vancomycin-resistant Enterococcus species and to investigate the influence of the microbiota and hospital environment on glycopeptide resistance. Materials and Methods: A total of 107 enterococcal isolates were collected from patients' rectal swab cultures and environmental samples taken for surveillance purposes. Multiplex Polymerase Chain Reaction (PCR) analysis was conducted to investigate specific virulence genes (esp, hyl, asa1, cyl, and galE) and glycopeptide resistance genes (vanA, vanB, van C1-C2, van D, vanE, and vanG). Additionally, perirectal swab cultures were obtained from patients without vancomycin-resistant enterococcal colonization to investigate the presence of glycopeptide resistance genes in their microbiota. Results: Seven isolates (6.5%) were identified as infectious agents. The most common vancomycin resistance genes were vanA (23.3%), followed by vanA + vanB (14%) and vanB + vanD (14%), respectively. The Random Amplified Polymorphic DNA Polymerase Chain Reaction (RAPD-PCR) method showed that patient surveillance and environmental isolates were clonally related. Moreover, microbiota analysis of patients without vancomycin-resistant enterococcal colonization revealed Clostridium spp. in two patients and Lactobacillus spp. in one patient, with the vanG gene found in the microbiota of only one (2.5%) patient. Conclusion: The detection of genes responsible for dissemination indicates that colonized isolates also have the potential for infection, and the hospital environment plays a primary role in the acquisition of vancomycin-resistant enterococci. [ABSTRACT FROM AUTHOR]

The present study was performed to explore the bactericidal effect of ozone micronano bubbles (OMNBs) against Pseudomonas aeruginosa, Escherichia coli (as gram-negative bacteria), Enterococcus faecalis, and Staphylococcus aureus (gram-positive bacteria). The effects of conventional ozonation (CO) or macrobubbles were also investigated for comparison. Three rates of ozone (10, 5, and 1.7 g/h) in both forms (OMNB and CO) were employed in different time contacts. Samples were collected at different contact times. The most significant bactericidal effect of OMNB was observed in P. aeruginosa and S. aureus at 5 g/h ozone, which killed 100% of these bacteria after 8 and 5 min, respectively, whereas the kill times by CO at the same rates were 120 min for P. aeruginosa and 90 min for S. aureus, E. coli, and E. faecalis showed the same pattern of kill time, 60 and 60 min by CO and 3 and 2 min by OMNB, respectively. Results showed that the removal efficiency was significantly increased compared to the ordinary ozonation at the same ozone rates. According to the results of this study, disinfection of water contaminated with these bacteria can be effectively performed using OMNBs to accelerate and increase the efficiency of the disinfection process. The results may open a new horizon to disinfect medical and food processing instruments and surfaces more effectively without remaining residuals and harm to the environment. [ABSTRACT FROM AUTHOR]

Aims Enterocins K1 and EJ97 have specific antimicrobial activity against Enterococcus faecium and Enterococcus faecalis , respectively. The aim of this study was to investigate the utility of these enterocins for in vivo treatment of systemic enterococcal infections. Methods and results The antimicrobial effect in blood was analysed and compared against the effect in saline. Colony forming unit counts revealed that the enterocins killed all the bacteria within 1 hour. Additionally, the bactericidal effect against E. faecalis was more rapid in blood, indicating a possible synergy between EntEJ97 and blood. Importantly, no enterocin resistant mutants emerged in these experiments. Injecting the enterocins intraperitoneally in an in vivo mouse model and using fluorescence and minimum inhibitory concentration determination to estimate concentrations of the peptides in plasma, indicate that the enterocins exist in circulation in therapeutic concentrations. Alanine aminotransferase detection, and haemolysis analysis indicates that there is no detectable liver damage or haemolytic effect after injection. Conclusions The study revealed that EntK1 and EntEJ97 are able to kill all bacteria ex vivo in the presence of blood. In vivo experiments determine that the enterocins exist in circulation in therapeutic concentrations without causing liver damage or haemolysis. Future experiments should test these peptides for treatment of infection in a relevant in vivo model. [ABSTRACT FROM AUTHOR]

Bloodstream infections (BSIs) account for 18% of bacterial infections in the first year after solid organ transplantation (SOT). Enterococcus accounts for up to 20% of BSIs in this population, with vancomycin‐resistant enterococcus (VRE) posing a particular risk. This is a retrospective, case‐control study of adult liver and kidney transplant recipients between 01/01/2016 and 06/30/2021 that characterizes the epidemiology and outcomes of enterococcal BSIs in liver and kidney transplantations at a single institution. Subjects with an enterococcal BSI within the first 6 months post‐transplant were compared to those with non‐enterococcal BSIs in the same period. We identified 26 subjects with enterococcal BSIs and 28 controls with non‐enterococcal BSIs (n = 54; 10.3%). Cases were mostly liver transplant recipients (n = 20; 77%) with a median MELD at transplant of 33 (range 14–43); controls included 14 KT recipients (50%). Groups differed significantly (all p <.05) by factors including perioperative transfusion requirements, need for reoperation, and number of interventions post‐transplant. Cases had a median time of 25.5 days to infection and controls 100.5 days (p <.0001). There were no differences in 1‐year mortality between the groups. Enterococcus faecium was the predominant species of Enterococcus (n = 23; 88.5%), with a majority (91.3%) of the isolates being VRE. In our liver and kidney transplants, enterococcal BSIs occurred early among liver transplant recipients. The high incidence of VRE among E. faecium isolates in this population warrants further investigation into the optimal approach to empiric antimicrobials for bacteremia in the early post‐transplant period. [ABSTRACT FROM AUTHOR]

Introduction: Prevalence of antibiotic resistance (AR) during the coronavirus 2019 (COVID-19) pandemic was higher than pre-pandemic times. This study determined the prevalence and patterns of AR among Gram-positive and negative bacteria before, during and after COVID-19 in Saudi Arabia and identified the associated factors. Methodology: A retrospective cross-sectional study was employed to identify patients with positive AR bacteria between March 2019 and March 2022. The bacterial isolates and patients' data were identified from laboratory and medical records departments retrospectively. Binary logistic regression analysis was performed to identify the factors associated with AR and deaths. Multinominal logistic regression was applied to confirm the factors associated with AR classification. Results: AR Gram-negative bacteria decreased during and after the pandemic. However, S. aureus showed a negligible increase in resistance rate after pandemic, while E. faecium, recorded a higher-than-average resistance rate during the pandemic. The prevalence of pan drug resistance (PDR) during the pandemic (85.7%) was higher than before (0%) and after (14.3%), p = 0.001. The length of stay and time were significant predictors for AR classification. The odds of multi drug resistance (MDR) development to PDR during the pandemic were 6 times higher than before and after (OR = 6.133, CI =, p = 0.020). Age, nationality, COVID-19 infection, smoking, liver disease, and type and number of bacteria were associated with death of patients with positive AR. Conclusions: Further studies are recommended to explore the prevalence of PDR and to justify the increased rates of E. faecium AR during the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Purpose: To examine the occurrence of virulence factors in Enterococcus faecium strains isolated from urinary tract infections (UTIs) and perform genotyping of the isolated strains using RAPD-PCR. Method: A total of seventy-five (75) E. faecium strains isolated from UTIs underwent molecular and biochemical testing for verification. Sensitivity testing and identification of virulence factors were conducted using antimicrobial tests. Results: Enterococcus faecium was detected in 53.57 % (75 out of 140) of urine samples in individuals suspected of having urinary tract infections. Additionally, all isolated strains demonstrated the ability to produce biofilm, with biofilm reactions observed in every E. faecium isolate. The strains exhibited either a strong (80 %), moderate (13.33 %) or weak (6.67 %) biofilm reaction. The highest antibiotic resistance in E. fascium isolates was related to penicillin and cotrimoxazole (83.33 and 80 %, respectively) while the lowest resistance was related to nitrofurantoin (26.67 %). The ebp C and ebp B were reported at 93.33 and 92 %, respectively, for E. faecium. The prevalence of ccf, cpd, cob and ebpA in E. fascium isolates was reported at 6.66, 13.33, 6.66, and 86.66 %, respectively. The RAPD-PCR analysis revealed the presence of 20 distinct molecular clusters, determined based on a similarity threshold of over 80 %. Conclusion: This study demonstrates the spread of multidrug-resistant E. faecium strains isolated from urinary tract infections (UTI). Being a quick and cost-effective method, RAPD typing has been used to show clonal relatedness and to trace possible sources of organisms for epidemiological purposes. [ABSTRACT FROM AUTHOR]

Background: Asymptomatic bacteriuria (ASB) during pregnancy can lead to symptomatic urinary tract infection (UTI), with increased fetal and maternal morbidity and mortality. We evaluated the incidence, clinical and microbiological profile, and outcome of ASB in pregnant women attending our antenatal clinic. Materials and Methods: This prospective study was conducted on 3769 pregnant women in a routine antenatal clinic at a tertiary care center. Participants were divided into two groups, ASB and non-bacteriuria. Data were collected in a standard proforma and analyzed using the software Statistical Package for the Social Sciences (SPSS) v. 20. Results: The incidence of ASB was 3.29% (124/3769). Majority of the women were in the age group of 21-30 years (78.76%, n = 89). Escherichia coli (61.06%) was the most common organism isolated. Maternal anemia (30.08% and 2.93% in the ASB and non-bacteriuria groups, respectively), low birth weight (LBW; 42.5% and 27.98% in the ASB and non-bacteriuria groups, respectively), intrauterine death (4.4% and 1.4% in the ASB and non-bacteriuria groups, respectively), and preterm delivery (37.2% and 22.31% in the ASB and non-bacteriuria groups, respectively) were were associated with ASB (P = 0.001). Conclusion: ASB was associated with maternal anemia, preterm delivery, intrauterine death, and LBW. Early detection and treatment of ASB may result in favorable maternal outcome. [ABSTRACT FROM AUTHOR]

Both geraniol and the products of its transformation, thanks to their beneficial properties, find a variety of applications in cosmetics. Due to their antioxidant and moisturizing properties, these compounds can be added to skin care products such as face creams, lotions, oils, and masks. In addition, these compounds show some antibacterial and antifungal properties, making them suitable for application in skin care products to help fight against bacteria or fungi. This study determined the antimicrobial activity of geraniol and the compounds which were formed during its transformation in relation to selected Gram-positive bacteria, and the preliminary assessment was made whether these compounds can act as ingredients of preparations with potential antimicrobial activity in the treatment of various human diseases (for example diseases of the skin, digestive system, or urinary tract). In addition, this work presents studies on the microbiological purity of cream samples obtained with different contents of geraniol and its transformation products (contents of the tested compounds: 0.5%, 1.5%, 2.5%, 4%, 8%, and 12%). Antibacterial activity tests were performed using the disc diffusion method against Gram-positive cocci, including the reference strains Staphylococcus aureus ATCC 29213 and Enterococcus faecalis ATCC 29212, and against the clinical strains Staphylococcus aureus MRSA, Staphylococcus epidermidis, Enterococcus faecalis VRE VanB, Enterococcus faecium VRE VanA, and Enterococcus faecium VRE VanB. The most active ingredient against bacteria of the Staphylococcus genus was citral, followed by linalool and then geraniol. During our tests, in the case of bacteria of the Enterococcus genus, citral also showed the highest activity, but linalool, ocimenes, and geraniol showed a slightly lower activity. Moreover, this study examined the microbiological purity of cream samples obtained with various contents of geraniol and its transformation products. In the tests of the microbiological purity of cream samples, no growth of aerobic bacteria and fungi was found, which proves the lack of microbiological contamination of the obtained cosmetic preparations. On this basis, it was assessed that these compounds have preservative properties in the prepared creams. The addition of the analyzed compounds also had influence on the durability of the creams and had no effect on the change in their consistency, did not negatively affect the separation of phases during storage, and even had a positive effect on organoleptic sensations by enriching the smell of the tested samples. [ABSTRACT FROM AUTHOR]

Background: The incidence of comorbidity between type 2 diabetes mellitus (T2DM) and metabolic-associated fatty liver disease (MAFLD) is high, and patients tend to be younger. When people develop metabolic diseases such as T2DM and MAFLD, the original homeostasis of the gut microbiota in the body is disrupted, and gut flora drift occurs. This study investigated the relationship between the number of gut flora and MAFLD in young-onset T2DM. Methods: This retrospective study analyzed 44 adolescent T2DM patients who were divided into a non-MAFLD group and a MAFLD group. Anthropometric measurements, clinical and biochemical markers, inflammatory markers, thyroid function assessments, and stool specimens were collected. Real-time PCR was performed to quantify several important gut flora constituents at the genus level. Student's t-test and the chi-square test were applied for group comparisons, and binary regression models were used to explore the relationship between gut flora and MAFLD in young-onset T2DM. Results: Among the 44 subjects, 26 (59.1%) were diagnosed with MAFLD, and 18 (40.9%) were not. Compared with the non-MAFLD group, body mass index (BMI), abdominal circumference, and levels of blood uric acid and thyroid stimulating hormone (TSH) in the MAFLD group were significantly increased, and age level and high-density lipoprotein cholesterol (HDL-C) were significantly decreased (p < 0.05). Compared with the non-MAFLD group, the abundance of Faecalibacterium prausnitzii and Bifidobacterium in the MAFLD group was significantly reduced, and the abundance of Enterococcus and Lactobacillus was significantly increased (p < 0.05). In the multivariate regression analysis, Faecalibacterium prausnitzii and Bifidobacterium were independent protective factors for MAFLD in young-onset T2DM, after excluding confounding factors. Conclusion: In young-onset T2DM, there was a difference in gut flora between patients with MAFLD and those without MAFLD. Faecalibacterium prausnitzii and Bifidobacterium were independent protective factors for MAFLD in young-onset T2DM. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance is presently one of the leading causes of death worldwide. The surveillance of different environments, namely, wastewater treatment plants (WWTPs), as hotspots of antibiotic-resistant bacteria, has become crucial under the One Health approach. This study aimed to characterize, phenotypically and genotypically, antibiotic-resistant bacteria along a WWTP receiving domestic and industrial sewage. Four sampling sites, representing distinct treatment points of the WWTP, were selected for sampling bacterial isolation in selective media supplemented, or not, with antibiotics, and subsequent antimicrobial susceptibility testing. Antibiotic resistance encoding genes were screened by molecular methods. A total of 50 bacterial isolates were obtained, 50% of which were affiliated with the genus Enterococcus. The antimicrobial susceptibility testing revealed antibiotic phenotypic resistance in isolates obtained from all the four treatment points of the wastewater samples, with resistance to tetracycline (32.5%) and ampicillin (25%) being the most common. Three isolates were found to be multidrug resistant and were affiliated with the genera Citrobacter, Shigella and Klebsiella. Molecular screening revealed the presence of tet(M), blaTEM, blaSHV and blaCTX-M, as well as class 1 integrons carrying dfrA25, ANT(3″)-IIa and aadA6 genes. This study highlights the relevance of bacterial isolation and their antimicrobial susceptibility evaluation in WWTP systems since antibiotic-resistant strains were found from the raw influent to the final effluent discharged into the environment, denoting the need for surveillance and containment measures. [ABSTRACT FROM AUTHOR]

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the assessment of the application for renewal of the authorisation of Cylactin® as a zootechnical feed additive for cats and dogs. The active agent of the additive is Enterococcus lactis NCIMB 10415 and the micro‐encapsulated formulation, Cylactin® LBC ME5 PET, was assessed. The applicant has provided evidence that the additive currently on the market complies with the existing conditions of authorisation. The Panel concluded that the additive remains safe for cats and dogs. Regarding user safety, the additive was not shown to be skin and eye irritant, but it should be considered a respiratory sensitiser. No conclusions can be drawn on the skin sensitisation. There is no need for assessing the efficacy of the additive in the context of the renewal of the authorisation. [ABSTRACT FROM AUTHOR]

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of Enterococcus lactis DSM 22502 as a technological feed additive for all animal species. The applicant provided evidence that the additive currently on the market complies with the existing conditions of authorisation. There is no new evidence that would lead the FEEDAP Panel to reconsider its previous conclusions regarding the safety and efficacy of the additive. The FEEDAP Panel concluded that E. lactis remains safe for all animal species, consumers and environment under the authorised conditions of use. Regarding the user safety, the Panel concluded that the additive is not irritating to the skin or eyes. No conclusions can be drawn on the potential of the additive to cause skin sensitisation, but it is considered to be a respiratory sensitiser. There is no need for assessing the efficacy of the additive in the context of the renewal of the authorisation. [ABSTRACT FROM AUTHOR]

Chronic wounds, defined as those which remain open and inflamed for greater than six weeks, are a major area of clinical concern. Resulting in thousands of amputations per year and billions of dollars spent globally in treatment, chronic wounds are notoriously difficult to successfully treat. Two hallmarks of chronic wounds are that they are thought to harbor biofilm-associated bacteria and tend to be polymicrobial. While the research literature has repeatedly demonstrated the effects of biofilms on wound persistence and the changes to the efficacy of antibiotics, few studies have demonstrated what effect the polymicrobial condition has on the antibiotic tolerance of bacteria. To further explore this, four species of clinically relevant wound pathogens (Pseudomonas aeruginosa, Acinetobacter baumanii, Staphylococcus aureus, and Enterococcus faecalis) were tested in mono- and polymicrobial conditions using the current gold-standard methods for determining antibiotic susceptibility. Noticeable differences in antibiotic tolerance were observed in the polymicrobial condition, including both increased and decreased susceptibility, depending on the antibiotic used. Our data demonstrate that the current clinical methods used for testing antibiotic susceptibility can generate results that are not representative of the infection environment, which may contribute to treatment failure and persistence of polymicrobial infections. [ABSTRACT FROM AUTHOR]

In this study, various functional and probiotic attributes of the Enterococcus faecium 9 N‐2 strain isolated from village‐style white cheese were characterized, while also assessing its safety. To achieve this, we conducted an in vitro analysis of several key probiotic properties exhibited by the 9 N‐2 strain. Notably, this strain demonstrated robust resilience to low pH, high bile salt concentrations, lysozyme, pepsin, pancreatin, and phenol. Furthermore, this strain displayed exceptional auto‐aggregation capabilities and moderate co‐aggregation tendencies when interacting with Escherichia coli. The cell‐free supernatant derived from strain 9 N‐2 exhibited significant antimicrobial activity against the tested pathogens. The strain exhibited resistance to gentamicin, meropenem, and bacitracin, while remaining susceptible to vancomycin and various other antibiotics. Furthermore, it was found that E. faecium 9 N‐2 possessed the capacity to produce the phytase enzyme. When all the results of this study are evaluated, it is thought that 9 N‐2 strain has superior probiotic properties, and therefore it can be used as probiotic in food, medicine, and animal feed in the future. In addition, further in vivo tests should be performed to fully understand its effects and mechanisms of action and to confirm its safety and probiotic effects. Further research and clinical trials are also needed to identify new strains with potential probiotic properties. [ABSTRACT FROM AUTHOR]

Mucus is an integral polydisperse molecule around the epithelium layer throughout the gastrointestinal tract and acts as a nutrition source for gut microbiota. In the present study, three Enterococcus strains, i.e., Enterococcus faecium KS2, Enterococcus faecium KS3, and Enterococcus gallinarum KS4, having mucin degrading ability, were isolated from human feces and identified by metagenomic technique. The cultures exhibited halos when grown in a mucin-containing medium, whereas quantitative data indicated a decrease in oligosaccharide concentration ranging between 28.74 and 73.05%, further confirming its degradation behavior. The physiological properties revealed that E. gallinarum KS4 lacks virulence, whereas E. faecium KS2 and E. faecium KS3 had the virulence factors. All identified isolates could tolerate pH 2.0 for up to three hours and exhibited survivability ranging between 75 and 111%. They also exhibited more than 70% survivability after eight hours against 0.5% (w/v) bile concentration. Antibiotic susceptibility data revealed that the KS2 strain showed susceptibility against 12 out of 26 antibiotics, including tetracycline, chloramphenicol, gentamicin, and kanamycin. At the same time, KS3 did not show susceptibility against ceftazidime, cefixime, and nalidixic, while E. gallinarum KS4 strain was susceptible to all tested antibiotics except cefixime and nalidixic. The study highlights mucin degrading behavior of human-derived Enterococcus strains and physiological traits specifically depicted E. faecium KS2 and KS3 as opportunistic pathogens. However, E. gallinarum KS4 showed promising functional attributes and required to be corroborated using a suitable in-vivo model. [ABSTRACT FROM AUTHOR]

Emergence and spread of antibiotics resistance among bacteria poses a serious concern for human health and disease therapy. In addition to this, novel pathogens are also surfacing rapidly. Discovery and development of newer, potent antimicrobial and therapeutic agents is constantly r equired. Soil is perplexing at different climatic conditions thereby providing variable source for the production of antibiotic producing microorganisms. Bacteriocin is a proteinaceous substance produced by bacteria which inhibits the growth of closely or exactly related bacterial strains. It is natural, safe secondary metabolite and its development and need for better antibiotic spectrum is always in high demand. In the present investigation, the bacteriocin producing microorganisms were isolated from the local rhizospheric soil samples. The isolates were subject to antibacterial susceptibility test against the common pathogenic bacteria i.e., Pseudomonas, Aeromonas, Bacillus and Escherichia coli by agar well diffusion method. The prominent zone of inhibition shown by isolate strains was recorded. Out of the 11 isolates, 5 isolated bacterial strains displayed significant inhibitory activity against the pathogenic bacteria. For further identification, biochemical tests were performed for these strains. These bacterial strains were identified with high similarity to Streptococcus sp., Enterococcus and Gemella berger. This investigation indicates that these bacteria have great potential for the production of antimicrobial property and this can be further characterized and utilized to control the growth of microbes in the future. [ABSTRACT FROM AUTHOR]

Bacterial infections are common after liver transplantation (LT) and cause serious morbidity and mortality. In our center, prolonged selective digestive decontamination (SDD) is the standard of care, which may lead to a reduced number and severity of bacterial infections. The aim of the current study was to investigate bacterial infection rates, the causative pathogens, localization, and the possible influence of SDD within the first year after LT. A retrospective single-center cohort study was performed. Patients within their first year after LT between 2012 and 2017 were included. Patients received SDD for 3 weeks immediately after LT. The type of infection, bacterial subtype, CSI classification, severity, and potential interventions were recorded. One hundred eighty-six patients were included in the study. Seventy-eight patients (41.9%) had a bacterial infection within the first year after LT. The most common types of infection were cholangitis (25.8%) and secondary infected abdominal fluid collections (25.3%). The most common bacteria were Gram-positive enterococcal- (36.5%) and Gram-negative enterobacterial species (34.2%). 35.5% of the infections occurred within the first month after LT, mainly caused by Gram-positive bacteria (76.7%). Cholangitis and infected abdominal fluid are the most common types of infection within one year after LT, mainly caused by enterococcal- and enterobacterial species. Within the first month after LT, infections were mostly caused by Gram-positive bacteria, which could be a consequence of protocol use of SDD. The results can be used for the choice of empirical antibiotic therapy based on the most common types of bacteria and the time frame after LT. [ABSTRACT FROM AUTHOR]

Statement of the Problem: Endodontic efforts are focused on eliminating intracanal pathogens. Applying intracanal medicament for infected teeth is beneficial for achieving better antibacterial effects in endodontic treatments. Different intracanal medicaments should be assessed and compared for this purpose. Purpose: The aim of this study was to assess the antibacterial efficacy of Citrullus colocynthis seed extract comparing to Ca(OH)2 on teeth contaminated with Enterococcus faecalis. Materials and Method: In this in vitro study, a novel strain of Enterococcus faecalis (Enterococcus spp. ATCC 19433) yielded from the root canal treated tooth with persistent apical periodontitis. The canals of 78 human single-rooted extracted teeth were contaminated with mentioned strain and treated with Citrullus colocynthis essential oil and Ca(OH)2 for 1, 7, and 14 days. To determine the chemical composition of the oils, gas chromatographymass spectrometry (GC–MS) was applied. The percentage reduction from baseline c.f.u./mL values was estimated. Results: Oleic acid, benzoic acid, and gallic acid were the major contents of Citrullus colocynthis essential oil. The c.f.u./mL count decreased considerably as contact duration rose for both medicaments. After 7 days, a statistically significant difference was identified between the medicaments. Citrullus colocynthis showed higher antimicrobial efficacy. However, after 14 days, no substantial difference was found. Conclusion: Citrullus colocynthis essential oil, displayed great antimicrobial efficacy against Enterococcus faecalis higher than Ca(OH)2 over the first week contact period. [ABSTRACT FROM AUTHOR]

Enterococcus faecalis is the most common enterococcal species associated with infective endocarditis and 1 of the most commonly detected bacteria in cases of secondary/persistent endodontic infection (SPEI). Antimicrobial resistance is a global public health concern. This review aimed to answer the following research question: "Is there a change in the antibiotic resistance profile in clinical strains of E. faecalis over the years?". P (population) - patients with SPEI, I (intervention) –endodontic retreatment, C (comparison) -not included, O (outcome) - profile of Enterococci resistance and susceptibility to systemic antibiotics used. Two authors independently performed study selection, data extraction, and risk of bias assessment. The literature search was conducted using the following electronic databases: PubMed, Scopus, EMBASE, Web of Science, and Medline. Clinical studies in which Enterococci strains were isolated to assess their antimicrobial resistance were included. Eleven clinical trials were included. Overall, E. faecalis isolated from teeth with SPEI presented an intermediate resistance to 16 antibiotics. In recent years, E. faecalis showed a little resistance to amoxicillin (without clavulanate) and benzylpenicillin. Erythromycin and rifampicin presented an increase in the intermediate-resistance status between the first and the last studies. E. faecium presented intermediate-resistance results. The most effective drugs remain the combination of amoxicillin and clavulanate, followed by amoxicillin and benzylpenicillin. In patients allergic to penicillin derivatives, moxifloxacin and azithromycin may be indicated with caution. The antibiotics with the highest pattern of resistance against E. faecalis are clindamycin, gentamicin, metronidazole, and rifampicin and are therefore, contraindicated in cases of SPEI. Very few clinical studies using a microbiological approach in teeth with endodontic failure have been carried out to improve the efficacy of prophylactic regimens. However, as bacteria periodically develop resistance to the main drugs used, regular studies should be carried out on the action of these drugs in infection control. [ABSTRACT FROM AUTHOR]

Background. Honey is a nutritious food made by bees from nectar and sweet deposits of flowering plants and has been used for centuries as a natural remedy for wound healing and other bacterial infections due to its antibacterial properties. Honey contains a diverse community of bacteria, especially probiotic bacteria, that greatly affect the health of bees and their consumers. Therefore, understanding the microorganisms in honey can help to ensure the quality of honey and lead to the identification of potential probiotic bacteria. Methods. Herein, the bacteria community in honey produced by Apis cerana was investigated by applying the next-generation sequencing (NGS) method for the V3≥V4 hypervariable regions of the bacterial 16S rRNA gene. In addition, lactic acid bacteria (LAB) in the honey sample were also isolated and screened for in vitro antimicrobial activity. Results. The results showed that the microbiota of A. cerana honey consisted of two major bacterial phyla, Firmicutes (50%; Clostridia, 48.2%) and Proteobacteria (49%; Gammaproteobacteria, 47.7%). Among the 67 identified bacterial genera, the three most predominant genera were beneficial obligate anaerobic bacteria, Lachnospiraceae (48.14%), followed by Gilliamella (26.80%), and Enterobacter (10.16%). Remarkably, among the identified LAB, Lactobacillus kunkeei was found to be the most abundant species. Interestingly, the isolated L. kunkeei strains exhibited antimicrobial activity against some pathogenic bacteria in honeybees, including Klebsiella spp., Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa and Staphylococcus aureus. This underscores the potential candidacy of L. kunkeei for developing probiotics for medical use. Taken together, our results provided new insights into the microbiota community in the A. cerana honey in Hanoi, Vietnam, highlighting evidence that honey can be an unexplored source for isolating bacterial strains with potential probiotic applications in honeybees and humans. [ABSTRACT FROM AUTHOR]

Background: Bloodstream infections (BSI) caused by a wide range of bacterial and fungal pathogens are associated with high rates of morbidity and mortality. Based on an estimate in 2017, the number of BSI incidences in Ontario is 150 per 100,000 population. The epidemiology of BSIs may be affected by many factors, including the social and travel restrictions and increased rates of hospitalizations in Ontario during the coronavirus disease 2019 (COVID-19) pandemic. Objectives: This study aimed to assess the changes in the microbiology of BSIs in Ontario during the COVID-19 pandemic compared to the pre-pandemic period. Methods: Retrospective blood culture data (n=189,106) from LifeLabs Ontario (July 2018 to December 2021) were analyzed. Blood culture positivity rates for common bacterial pathogens were compared between pre-COVID-19 (July 2018 to March 2020) and COVID-19 (April 2020 to December 2021) periods in community and hospital settings, using the chi-square test for significance. Results: During the COVID-19 period, blood culture positivity rates in the community remained the same, while hospital rates increased by approximately threefold (p=0.00E-00). In the community, the isolation rates of most bacterial species remained unchanged, except for an increase in Enterococcus spp. and a decrease in Salmonella spp. The rates of antibiotic-resistant organisms (AROs) also significantly decreased in the community. In hospitals, all bacterial species, including AROs, showed significant increases in isolation rates during the COVID-19 period. Conclusion: The study revealed shifts in the microbiology of BSIs and suggests changes in the epidemiology of BSIs during the COVID-19 pandemic in Ontario, both in hospitals and in the community. [ABSTRACT FROM AUTHOR]

This study aimed to assess the prevalence of Staphylococcus aureus and Enterococcus sp. among pregnant women who visit the General Hospital in Delta Central Senatorial District, Nigeria. Samples were collected from the vaginal and rectum areas of pregnant women attending the General Hospitals of Abraka, Oghara, Udu, Ughelli North and Ughelli South. Bacteriological and biochemical analyses were conducted to isolate, characterize, and identify the bacteria. Two types of bacteria were found; Enterococcus sp. and Staphylococcus sp. The study result showed that Staphylococcus aureus (13.7%) was more prevalent than other isolates and was found in samples obtained from Udu General Hospital. In comparison, Ughelli South General Hospital had the lowest prevalence for S. aureus (7.9%). Samples from Oghara General Hospital had the highest prevalence for Enterococcus sp. (3.7%) while the lowest prevalence for Enterococcus sp. (1.1%) was obtained from Ughelli South General Hospital. S. aureus (51.6%) was found to be the most prevalent bacterium, while Enterococcus sp. (11.1%) was the least prevalent. The bacterial load from the vaginal swab samples was higher than that of rectum swab samples, which suggests that pregnant women attending these hospitals may have infections. The total bacterial count among pregnant women was highest in samples obtained from Udu General Hospital (5.4±0.5), followed by Abraka (5.0±0.6), Oghara (4.8±0.2), and Ughelli North (4.5±0.15), and while the least count was recorded from samples obtained from Ughelli South General Hospital (3.0±0.2). This study helps manage and plan future medical treatments. Pregnant women should be screened early in their pregnancies, between the 12th and 16th weeks, which is the second trimester, and treated appropriately to avoid complications that arise from untreated infections. [ABSTRACT FROM AUTHOR]

Beer stability, influenced by physical, chemical, and biological factors, poses a considerable challenge for breweries. Biological stability, as a major concern, is effectively managed through practices such as good hygiene, pasteurization, and filtration. Microbiological contamination, often recognizable by increased turbidity or off-flavours, is influenced by temperature, with optimal conditions promoting the growth of specific microorganisms. Lower temperatures slow down flavour changes and chemical reactions in beer, impacting its non-biological stability. This case study explores the impact of storage temperature on autolysis off-flavour development in 10 different unfiltered and unpasteurized beers. The results showed that autolysis off-flavour occurred at both low and higher storage temperatures and that its dependence on the temperature was minimal. This unexpected fact was discovered mainly due to uncovered significant contamination of the commercial beers tested (wild yeasts, lactic acid bacteria, enterococci and coliform bacteria). For this reason, the concentration of cells in the beer appeared as a more influential factor in the development of off-flavours, including autolysis, than the storage temperature. The partial results need to be studied in more detail, nevertheless, we felt it was important to publish the revelation of a strong contamination of beers purchased from regular stores for our experiments. At this point it can already be concluded that the low storage temperature did not help to prevent the development of the contamination and the associated sensory deterioration of the beers. [ABSTRACT FROM AUTHOR]

Oral diseases are one of the biggest public health problems worldwide, caused by opportunistic pathogens such as Streptococcus mutans and Enterococcus faecalis. Cyperus articulatus (priprioca) is a plant conventionally used in traditional medicine in the Amazon region. However, little is known about the possible dentistry-related uses of extracts from the rhizomes and solid waste generated by the extraction of essential oils from this vegetable. This study aimed to investigate the chemical composition of volatile compounds and antimicrobial activity through the Minimum Inhibitory Concentration test (MIC and assessment of the toxicity by Hens Egg Test-Chorion Allantoic Membrane (HET-CAM) of the ethanolic extracts from Cyperus articulatus intact rhizomes and solid waste. We identified sesquiterpenes as the main constituents, strong antimicrobial activity of the ethanolic extract of intact rhizomes against S. mutans (MIC = 0.29 mg/mL), moderate antimicrobial activity against E. faecalis of the extract obtained from the solid waste (MIC = 1.17 mg/mL), and absence of toxicity for both tested extracts. The absence of irritation and the antibacterial activity of the ethanolic extract from C. articulatus rhizomes and solid waste reveal its potential for use in the alternative control of bacteria that cause oral infections and may present economic viability as a raw material for dental products. [ABSTRACT FROM AUTHOR]

Listeria monocytogenes is a foodborne pathogen that contaminates food-processing environments and persists within biofilms on equipment, thus reaching final products by cross-contamination. With the growing demand for clean-label products, the search for natural antimicrobials as biopreservants, such as bacteriocins, has shown promising potential. In this context, this study aimed to evaluate the anti-listerial action of bacteriocins produced by Enterococcus lactis LBM BT2 in an alternative medium containing sugarcane molasses (SCM). Molecular analyses were carried out to characterize the strain, including the presence of bacteriocin-related genes. In the kinetic study on SCM medium E. lactis, LBM BT2 showed biomass and bacteriocin productions similar to those observed on a sucrose-based medium (control), highlighting the potential of the sugarcane molasses as a low-cost substrate. Stability tests revealed that the molecule remained active in wide ranges of pH (4–10) and temperature (60–100 °C). Furthermore, the proteolytic treatment reduced the biomolecule's antimicrobial activity, highlighting its proteinaceous nature. After primary purification by salting out and tangential flow filtration, the bacteriocin-like inhibitory substance (BLIS) showed bacteriostatic activity on suspended L. monocytogenes cells and against biofilm formation at a concentration of 0.625 mg/mL. These results demonstrate the potential of the produced BLIS as a biopreservative in the food industry. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has strained healthcare systems globally. Shortages of hospital beds, reassignment of healthcare workers to COVID-19-dedicated wards, an increased workload, and evolving infection prevention and control measures have potentially contributed to the spread of multidrug-resistant bacteria (MDRB). To determine the impact of the COVID-19 pandemic at the University Medical Center Ljubljana, a tertiary teaching hospital, we analyzed the monthly incidence of select bacterial species per patient from 2018 to 2022. The analysis was performed for all isolates and for MDRB isolates. The data were analyzed separately for isolates from all clinical samples, from blood culture only, and from clinical and surveillance samples. Our findings revealed an increased incidence density of patients with Enterococcus faecium, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa isolates from clinical samples during the COVID-19 period in the studied hospital. Notably, the incidence density of MDRB isolates—vancomycin-resistant E. faecium, extended-spectrum betalactamase-producing K. pneumoniae, and betalactam-resistant P. aeruginosa—from clinical samples increased during the COVID-19 period. There were no statistically significant differences in the incidence density of patients with blood culture MDRB isolates. We observed an increase in the overall MDRB burden (patients with MDRB isolates from both clinical and surveillance samples per 1000 patient days) in the COVID-19 period in the studied hospital for vancomycin-resistant E. faecium, carbapenem-resistant K. pneumoniae, and betalactam-resistant P. aeruginosa and a decrease in the methicillin-resistant S. aureus burden. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance is a critical challenge due to the overuse of conventional antimicrobials, and alternative solutions are urgently needed. This study investigates the efficacy of compounds derived from lactic acid bacteria (LAB) fermentation combined with antibiotics against multidrug-resistant pathogens isolated from clinical cases in a hospital setting. Strains of Escherichia coli, Klebsiella pneumoniae, and Enterococcus faecium and faecalis were isolated and selected from blood, respiratory, and urine samples. They were tested against the fermentation products from the Ingulados LAB collection (BAL5, BAL6, BAL8, BAL13, and BAL16), recognized for their antimicrobial efficacy against veterinary pathogens. The activity against multidrug-resistant (MDR) pathogens was evaluated initially, followed by synergy tests using checkerboard assays and subsequent analysis. Bioinformatic assessments and supernatant treatments were performed to characterize the nature of the compounds responsible for the antimicrobial activity. Notably, BAL16 exhibited significant growth inhibition against multidrug-resistant E. faecium. Synergy tests highlighted its combined activity with tetracycline through FICI and surface analysis and bioinformatic analysis unveiled the protein fraction containing bacteriocins as the underlying mechanism. This study highlights BAL16 fermentation products potential as valuable antimicrobial agents against MDR E. faecium infections, attributed to bacteriocins. Further in-depth studies are necessary for complete bacteriocin characterization. [ABSTRACT FROM AUTHOR]

From traditional Gifu ayu-narezushi, Leuconostoc, Latilactobacillus, and Enterococcus were isolated as dominant genera. Isolated strains of Leuconostoc mesenteroides showed high growth inhibition activity against Staphylococcus aureus and Escherichia coli. The isolated strain, Enterococcus lactis EC52, could produce 1-aminobutyric acid (GABA). These results indicated that Enterococcus lactis and Leuconostoc mesenteroides were lactic acid bacteria, which have GABA-producing and antimicrobial activities, respectively, in traditional Gifu ayu-narezushi. [ABSTRACT FROM AUTHOR]

Objective: The use of essential oils for the preparation of different nanoemulsions (NEa, NEb and NEc) and detect their biological activities. Methods: Nanoemulsiona were prepared by mixing the essential oil (10%) of Coriandrum seed of Coriandrum sativum, Ginger roots of Zingiber officinale, or Achillea leaves of Achillea clavennae), sterile water, and surfactants (Brij 30, Span 20, Triton X-100, Tween 60) in addition to the 0.1M Tris-HCl buffer (pH 7.22). The three prepared nanoemulsions were examined and characterized. Their antibacterial activities were examined against some multidrug-resistant Gram-positive and negative bacteria. Results: The maximum activity was recorded by NEb against Serratia marcescens, Staphylococcus aurous, Micrococcus luteus, Enterococcus faecalis, Streptococcus pyogenes, and Staphylococcus saprophyticus while lower activity was obtained against Klebsiella pneumonia and Escherichia coli. The minimum inhibitory concentrations (MICs) of the NEb ranged from 40--60 µl/ml of the nutrient broth. NEb affects the cell counts and morphology of S. marcescens and destroys the bacterial cells by reducing cell respiration and enhancing the cell permeability and leakage of protein, DNA, and potassium of the bacterial cell membrane. NEb recorded no toxicity against Artimia salina and HaCaT cell line. It decreases biofilm formation by 51%, bacterial infection, and cell attachment. Conclusion: This study suggests that NEs have great antibacterial activity against some human pathogens and process different modes of action, thus they can be used effectively to treat different bacterial infections. [ABSTRACT FROM AUTHOR]

The human body hosts complex communities of microorganisms, collectively known as the "microbiota," predominantly in the lower intestine. This microbiota, which consists of bacteria, viruses, and fungi, plays a vital role in the breakdown of various nutrients and maintenance of homeostasis. The microbiome, which represents the collective genetic content of these microorganisms, is intricately associated with human health and disease. Healthcare-associated infections (HCAIs), a major public health problem, contribute to high morbidity and mortality. Exposure to antibiotics, a primary risk factor for diseases, disrupts the microbiota and compromises its protective role. Age-related changes in the microbiota affect the onset and progression of various diseases by affecting the functional capacity and fitness of the host. Inanimate surfaces in built environments contribute to HCAIs by serving as potential reservoirs for microorganisms. Promising results have been observed with fecal microbiota transplantation (FMT) for treating Clostridium difficile infection, which is often associated with healthcare facilities. FMT prevents disease recurrence by restoring a healthy colonic microbiota and breaking the dysbiotic cycle. Furthermore, microbiota-based interventions have the potential to control emerging multidrug-resistant pathogens such as vancomycin-resistant enterococci and carbapenem-resistant Enterobacteriaceae. [ABSTRACT FROM AUTHOR]

This article evaluates a modified protocol for bacterial identification and antimicrobial susceptibility testing from positive blood culture bottles. The authors developed a modified protocol that includes an additional lysis step to improve accuracy. The study compared the modified protocol to the original and found that the modified protocol had a higher correct identification rate. The results suggest that the modified protocol may be a more effective method for direct identification and antimicrobial susceptibility testing. The study acknowledges limitations but highlights the potential benefits of the modified protocol. [Extracted from the article]

This study aimed to investigate the effects of commercial tattoo inks used in corneal tattooing on conjunctival microbiota. This prospective case control study consisted of 125 participants divided in the following three groups: 35 patients with corneal tattoos, 40 patients with corneal leukoma, and 50 healthy subjects. Corneal tattooing was performed in all the cases in this study using a tattoo pen machine and commercial tattoo ink. A total of 500 cultures were taken from 250 eyes of 125 individuals on chocolate and sheep blood agar. Bacteriological samples were taken from the inferior eyelid conjunctiva using a sterile cotton swab. Without any contact elsewhere, the swabs were smeared on bedside chocolate agars and 5% sheep blood agar. In tattooed eyes, bacterial growth was detected in 42.9% of the chocolate and sheep blood agar samples. In other healthy eyes of patients with corneal tattoos, 54.5% bacterial growth on chocolate agar and 57.1% on sheep blood agar were detected. No statistical difference was detected in the conjunctival microbiota of chocolate and sheep blood agar (p = 0.254, p = 0.134, respectively) in the tattooed eyes compared to the other eye of the individual. No statistically significant difference was found in terms of bacterial growth in tattooed, leukoma, or healthy eyes on chocolate and sheep blood agar (p = 0.408, p = 0.349). The growth rate of Staphylococcus epidermidis decreased by 33.3% (from 12 to 8) on chocolate agar in 35 tattooed eyes, and it decreased by 28.5% (from 14 to 10) on sheep blood agar, while gram-negative bacteria Brevundimonas diminuta, Acinetobacter lwoffii, and Psychrobacter faecalis were detected in three patients. Corneal tattooing using commercial dye does not affect conjunctival microbiota. In the past 3 years, 120 patients have been tattooed with commercial tattoo ink in Istanbul Medeniyet University Göztepe Training and Research Hospital. No complications related to infection were found in the 3-year follow-up. The gram-negative bacteria detected in the healthy control group and tattooed eyes were bacteria found on normal skin or in the respiratory tract. Although some gram-negative bacteria do not cause infection, careful eye examination, follow-up, and culture are required in suspicious cases. [ABSTRACT FROM AUTHOR]

Background and Objectives: Enterococcus faecalis (E. faecalis) is a primary pathogen responsible for dental abscesses, which cause inflammation and pain when trapped between the crown and soft tissues of an erupted tooth. Therefore, this study aims to use specific phages as an alternative method instead of classical treatments based on antibiotics to destroy multidrug-resistant E. faecalis bacteria for treating dental issues. Materials and Methods: In the current study, twenty-five bacterial isolates were obtained from infected dental specimens; only five had the ability to grow on bile esculin agar, and among these five, only two were described to be extensive multidrug-resistant isolates. Results: Two bacterial isolates, Enterococcus faecalis A.R.A.01 [ON797462.1] and Enterococcus faecalis A.R.A.02, were identified biochemically and through 16S rDNA, which were used as hosts for isolating specific phages. Two isolated phages were characterized through TEM imaging, which indicated that E. faecalis_phage-01 had a long and flexible tail, belonging to the family Siphoviridae, while E. faecalis_phage-02 had a contractile tail, belonging to the family Myoviridae. Genetically, two phages were identified through the PCR amplification and sequencing of the RNA ligase of Enterococcus phage vB_EfaS_HEf13, through which our phages shared 97.2% similarity with Enterococcus phage vB-EfaS-HEf13 based on BLAST analysis. Furthermore, through in silico analysis and annotations of the two phages' genomes, it was determined that a total of 69 open reading frames (ORFs) were found to be involved in various functions related to integration excision, replication recombination, repair, stability, and defense. In phage optimization, the two isolated phages exhibited a high specific host range with Enterococcus faecalis among six different bacterial hosts, where E. faecalis_phage-01 had a latent period of 30 min with 115.76 PFU/mL, while E. faecalis_phage-02 had a latent period of 25 min with 80.6 PFU/mL. They were also characterized with stability at wide ranges of pH (4–11) and temperature (10–60 °C), with a low cytotoxic effect on the oral epithelial cell line at different concentrations (1000–31.25 PFU/mL). Conclusions: The findings highlight the promise of phage therapy in dental medicine, offering a novel approach to combating antibiotic resistance and enhancing patient outcomes. Further research and clinical trials will be essential to fully understand the therapeutic potential and safety profile of these bacteriophages in human populations. [ABSTRACT FROM AUTHOR]

Increasing antimicrobial resistance in Enterococcus faecium necessitates the search for novel treatment agents, such as bacteriocins. In this study, we conducted an in vivo assessment of five bacteriocins, namely Lacticin Z, Lacticin Q, Garvicin KS (ABC), Aureocin A53 and Microbisporicin (NAI-107), against vanB-resistant Enterococcus faecium using a Galleria mellonella model. Our in vitro experiments demonstrated the efficacy of all five bacteriocins against vanB-resistant E. faecium with only NAI-107 demonstrating in vivo efficacy. Notably, NAI-107 exhibited efficacy across a range of tested doses, with the highest efficacy observed at a concentration of 16 µg/mL. Mortality rates in the group treated with 16 µg/mL NAI-107 were lower than those observed in the linezolid-treated group. These findings strongly suggest that NAI-107 holds promise as a potential alternative therapeutic agent for treating infections caused by resistant E. faecium and warrants further investigation. [ABSTRACT FROM AUTHOR]

Background: Dysbiotic biliary bacterial profile is reported in cancer patients and is associated with survival and comorbidities, raising the question of its effect on the influence of anticancer drugs and, recently, the suggestion of perichemotherapy antibiotics in pancreatic cancer patients colonized by the Escherichia coli and Klebsiella pneumoniae. Objective: In this study, we investigated the microbial communities that colonize tumours and which bacteria could aid in diagnosing pancreatic and biliary cancer and managing bile-colonized patients. Methods: A retrospective study on positive bile cultures of 145 Italian patients who underwent cholangiopancreatography with PC and EPC cancer hospitalized from January 2006 to December 2020 in a QA-certified academic surgical unit were investigated for aerobic/facultative-anaerobic bacteria and fungal organisms. Results: We found that among Gram-negative bacteria, Escherichia coli and Pseudomonas spp were the most frequent in the EPC group, while Escherichia coli, Klebsiella spp, and Pseudomonas spp were the most frequent in the PC group. Enterococcus spp was the most frequent Gram-positive bacteria in both groups. Comparing the EPC and PC, we found a significant presence of patients with greater age in the PC compared to the EPC group. Regarding Candida spp, we found no significant but greater rate in the PC group compared to the EPC group (11.7% vs 1.96%). We found that Alcaligenes faecalis was the most frequent bacteria in EPC than the PC group, among Gram-negative bacterial species. Conclusions: Age differences in gut microbiota composition may affect biliary habitats in our cancer population, especially in patients with pancreatic cancer. Alcaligenes faecalis isolated in the culture of bile samples could represent potential microbial markers for a restricted follow-up to early diagnosis of extra-pancreatic cancer. Finally, the prevalence of Candida spp in pancreatic cancer seems to trigger new aspects about debate about the role of fungal microbiota into their relationship with pancreatic cancer. [ABSTRACT FROM AUTHOR]

Background: In most of Europe and especially in Germany, there is currently a concerning rise in the number of hospital-acquired infections due to vancomycin-resistant Enterococcus faecium (VREfm). Therefore, there is a need to improve our understanding of the way VREfm spreads in hospitals. In this study, we investigated the molecular epidemiology of VREfm isolates from the first appearance at our university hospital in 2004 until 2010. There is only very scarce information about the molecular epidemiology of VREfm from this early time in Germany. Methods: Our analysis includes all available first VREfm isolates of each patient at our tertiary care center collected during the years 2004–2010. If available, additional consecutive VREfm isolates from some patients were analyzed. We used multilocus sequence typing (MLST) and core genome multilocus sequence typing (cgMLST) for the analysis and description of nosocomial transmission pathways as well as the detection of outbreaks. Results: VREfm isolates from 158 patients and 76 additional subsequent patient isolates were included in the analysis. Until 2006, detections of VREfm remained singular cases, followed by a peak in the number of VREfm cases in 2007 and 2008 with a subsequent decline to baseline in 2010. MLST and cgMLST analysis show significant changes in the dominant sequence types (STs) and complex types (CTs) over the study period, with ST192 and ST17 being responsible for the peak in VREfm cases in 2007 and 2008. The four largest clusters detected during the study period are comprised of these two STs. Cluster analysis shows a focus on specific wards and departments for each cluster. In the early years of this study (2004–2006), all analyzed VREfm stemmed from clinical specimens, whereas since 2007, approximately half of the VREfm were detected by screening. Of the 234 VREfm isolates analyzed, 96% had a vanB and only 4% had a vanA resistance genotype. Conclusions: This retrospective study contributes significant knowledge about regional VREfm epidemiology from this early VREfm period in Germany. One remarkable finding is the striking dominance of vanB-positive VREfm isolates over the entire study period, which is in contrast with countrywide data. Analysis of cgMLST shows the transition from sporadic VRE cases at our institution to a sharp increase in VRE numbers triggered by oligoclonal spread and specific outbreak clusters with the dominance of ST192 and ST17. [ABSTRACT FROM AUTHOR]

Enterococcus faecalis is a bacterium which accompanies us from the first days of our life. As a commensal it produces vitamins, metabolizes nutrients, and maintains intestinal pH. All of that happens in exchange for a niche to inhabit. It is not surprising then, that the bacterium was and is used as an element of many probiotics and its positive impact on the human immune system and the body in general is hard to ignore. This bacterium has also a dark side though. The plasticity and relative ease with which one acquires virulence traits, and the ability to hide from or even deceive and use the immune system to spread throughout the body make E. faecalis a more and more dangerous opponent. The statistics clearly show its increasing role, especially in the case of nosocomial infections. Here we present the summarization of current knowledge about E. faecalis, especially in the context of its relations with the human immune system. [ABSTRACT FROM AUTHOR]

Bioactive peptides (BPs) are molecules of paramount importance with great potential for the development of functional foods, nutraceuticals or therapeutics for the prevention or treatment of various diseases. A functional BP-rich dairy product was produced by lyophilisation of bovine milk fermented by the autochthonous strains Lactococcus lactis subsp. lactis ZGBP5-51, Enterococcus faecium ZGBP5-52 and Enterococcus faecalis ZGBP5-53 isolated from the same artisanal fresh cheese. The efficiency of the proteolytic system of the implemented strains in the production of BPs was confirmed by a combined high-throughput mass spectrometry (MS)-based peptidome profiling and an in silico approach. First, peptides released by microbial fermentation were identified via a non-targeted peptide analysis (NTA) comprising reversed-phase nano-liquid chromatography (RP nano-LC) coupled with matrix-assisted laser desorption/ionisation-time-of-flight/time-of-flight (MALDI-TOF/TOF) MS, and then quantified by targeted peptide analysis (TA) involving RP ultrahigh-performance LC (RP-UHPLC) coupled with triple-quadrupole MS (QQQ-MS). A combined database and literature search revealed that 10 of the 25 peptides identified in this work have bioactive properties described in the literature. Finally, by combining the output of MS-based peptidome profiling with in silico bioactivity prediction tools, three peptides (75QFLPYPYYAKPA86, 40VAPFPEVFGK49, 117ARHPHPHLSF126), whose bioactive properties have not been previously reported in the literature, were identified as potential BP candidates. [ABSTRACT FROM AUTHOR]

Background Enterococcus intestinal domination (EID), a state of dysbiosis wherein enterococci comprise ≥30% abundance within the microbiota, has been associated with Enterococcus bacteremia, graft-versus-host disease, and mortality in the allogeneic hematopoietic stem cell transplant (allo HCT) population. The acute leukemia (AL) chemotherapy population includes patients receiving intensive chemotherapy, but not all patients go on to have an allo HCT. The impact of EID on outcomes including mortality in the AL chemotherapy population is unknown. Methods Microbiota composition from weekly stool samples was analyzed using 16S ribosomal RNA gene sequencing. Patients were analyzed in 2 cohorts: AL chemotherapy cohort and allo HCT cohort. α -diversity and richness were calculated. Kaplan-Meier analysis was used to analyze mortality. Results A total of 929 stool samples were collected from 139 patients. Both allo HCT and AL cohorts had a decline in α-diversity and richness over the course of treatment that tended not to return to baseline months later. EID was observed in at least 1 sample in 36% of allo HCT patients and 49% of AL patients. Patients with observed EID had lower α-diversity over time. Similar to the HCT cohort, AL patients with EID had reduced overall survival. We identified 4 other genera that were commonly found in ≥30% relative abundance within the microbiota, but none were associated with mortality. In fact, in allo HCT, Bacteroides abundance ≥30% was associated with improved survival. Conclusions EID is associated with increased all-cause mortality in HCT and AL cohorts. Unlike EID, relative abundance ≥30% by other genera is not associated with increased all-cause mortality. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the chemical composition and antimicrobial and antioxidant activities of the essential oil from dried seeds of Xylopia aethiopica. The essential oil was obtained by hydrodistillation and analyzed by GC/FID and GC/MS. The essential oil yield was 1.35%. Forty-nine compounds were identified in the essential oil with 1,8-cineole (16.3%), β-pinene (14.8%), trans-pinocarveol (9.1%), myrtenol (8.3%), α-pinene (5.9%), and terpinen-4-ol (5.6%) as major components. The antimicrobial activity of this essential oil was studied using disk diffusion and broth microdilution methods on four bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa) and one fungus (Candida albicans). The essential oil exhibited excellent activity against S. aureus, E. faecalis, and C. albicans and moderate activity against E. coli. Among all strains tested, C. albicans showed the best sensitivity with a MIC of 50 mg/mL. The antioxidant activity was examined using a DPPH-free radical scavenging assay. The essential oil of X. aethiopica showed low antioxidant activity (IC50 = 784.604 ± 0.320 mg/mL) compared to that of ascorbic acid and the reference compound (IC50 = 0.163 ± 0.003 mg/mL). The results indicate that consumption of X. aethiopica seeds can reduce the virulence of food-borne pathogens and their resistance to antibiotics. [ABSTRACT FROM AUTHOR]

Enterococci, known for their resilience, are commonly found in food, the environment, and the gastrointestinal tracts of humans and animals. In recent research, six strains of enterococcus were isolated from bat guano. These include Enterococcus mundtii SRBG1, Enterococcus gallinarum SRBG3, Enterococcus faecium SRBG2, Enterococcus casseliflavus EC1, and Enterococcus devriesei CAU 1344. Identification was done using 16S DNA analysis. Each strain underwent evaluation for its technological properties (such as tolerances to various NaCl concentrations and temperatures, as well as amylolytic, β-galactosidase, lipolytic, and proteolytic activities, and EPS production) and selected probiotic properties (including safety profile, resistance to 0.3 percent bile salts and gastric juice with a pH of 2.5, lysozyme tolerance, and antibacterial and antibiofilm activities against four foodborne pathogens). The results were analyzed using Principal Component Analysis. This analysis revealed that E. mundtii SRBG1 and E. gallinarum SRBG3, followed by E. faecium SRBG2, were most closely associated with a broad range of technological characteristics and were subsequently used for fermenting skimmed milk. The rheological properties of the samples indicated a shear-thinning or non-Newtonian behavior. Furthermore, during storage of the fermented milk at 4 °C over periods of 1, 7, 14, and 21 days, there were no significant changes in bacterial count (at around 7 log10 CFU/mL) and pH when fermented with the three evaluated strains. [ABSTRACT FROM AUTHOR]

Background: Tranexamic acid (TXA) is an antifibrinolytic agent applied in orthopedic surgery and has been proven to reduce post-surgery infection rates. We previously showed that TXA also had an additional direct antimicrobial effect against planktonic bacteria. Therefore, we aimed to evaluate whether it has a synergistic effect if in combination with antibiotics. Materials and Methods: Three ATCC and seven clinical strains of staphylococci were tested against serial dilutions of vancomycin and gentamicin alone and in combination with TXA at 10 and 50 mg/ml. The standardized microtiter plate method was used. Minimal inhibitory concentrations (MICs) were calculated by standard visualization of well turbidity (the lowest concentration at which complete absence of well bacterial growth was observed by the researcher) and using the automated method (the lowest concentration at which ≥80% reduction in well bacterial growth was measured using a spectrophotometer). Results: Tranexamic acid-10 mg/ml reduced the MIC of vancomycin and gentamicin with both the standard method (V: 1-fold dilution, G: 4-fold dilutions) and the automated turbidity method (vancomycin: 8-fold dilutions, gentamicin: 8-fold dilutions). TXA-50 mg/ml reduced the MIC of gentamicin with both the standard turbidity method (6-fold dilutions) and the automated turbidity method (1-fold dilutions). In contrast, for vancomycin, the MIC remained the same using the standard method, and only a 1-fold dilution was reduced using the automated method. Conclusion: Ours was a proof-of-concept study in which we suggest that TXA may have a synergistic effect when combined with both vancomycin and gentamicin, especially at 10 mg/ml, which is the concentration generally used in clinical practice. [ABSTRACT FROM AUTHOR]

Background: An innovative intracanal medication formulation was introduced in the current study to improve the calcium hydroxide (Ca(OH)2) therapeutic capability against resistant Enterococcus faecalis (E. faecalis) biofilm. This in-vitro study aimed to prepare, characterize, and evaluate the antibacterial efficiency of Ca(OH)2 loaded on Gum Arabic (GA) nanocarrier (Ca(OH)2-GA NPs) and to compare this efficiency with conventional Ca(OH)2, Ca(OH)2 nanoparticles (NPs), GA, and GA NPs. Materials and methods: The prepared nanoparticle formulations for the tested medications were characterized using Transmission Electron Microscope (TEM) and Fourier-Transform Infrared Spectroscopy (FTIR). 141 human mandibular premolars were selected, and their root canals were prepared. Twenty-one roots were then sectioned into 42 tooth slices. All prepared root canals (n = 120) and teeth slices (n = 42) were divided into six groups according to the intracanal medication used. E. faecalis was inoculated in the samples for 21 days to form biofilms, and then the corresponding medications were applied for 7 days. After medication application, the residual E. faecalis bacteria were assessed using CFU, Q-PCR, and SEM. Additionally, the effect of Ca(OH)2-GA NPs on E. faecalis biofilm genes (agg, ace, and efaA) was investigated using RT-PCR. Data were statistically analyzed at a 0.05 level of significance. Results: The synthesis of NPs was confirmed using TEM. The results of the FTIR proved that the Ca(OH)2 was successfully encapsulated in the GA NPs. Ca(OH)2-GA NPs caused a significant reduction in the E. faecalis biofilm gene expression when compared to the control (p < 0.001). There were significant differences in the E. faecalis CFU mean count and CT mean values between the tested groups (p < 0.001) except between the Ca(OH)2 and GA CFU mean count. Ca(OH)2-GA NPs showed the least statistical E. faecalis mean count among other groups. SEM observation showed that E. faecalis biofilm was diminished in all treatment groups, especially in the Ca(OH)2-GA NPS group when compared to the control group. Conclusions: Ca(OH)2 and GA nanoparticles demonstrate superior anti-E. faecalis activity when compared to their conventional counterparts. Ca(OH)2-GA NPs showed the best antibacterial efficacy in treating E. faecalis biofilm. The tested NP formulations could be considered as promising intracanal medications. [ABSTRACT FROM AUTHOR]

Background: Although multidrug-resistant bacteria (MDR) are common in patients undergoing prolonged weaning, there is little data on their impact on weaning and patient outcomes. Methods: This is a retrospective analysis of consecutive patients who underwent prolonged weaning and were at a university weaning centre from January 2018 to December 2020. The influence of MDR colonisation and infection on weaning success (category 3a and 3b), successful prolonged weaning from invasive mechanical ventilation (IMV) with or without the need for non-invasive ventilation (NIV) compared with category 3c (weaning failure 3cI or death 3cII) was investigated. The pathogen groups considered were: multidrug-resistant gram-negative bacteria (MDRGN), methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus spp. (VRE). Results: A total of 206 patients were studied, of whom 91 (44.2%) showed evidence of MDR bacteria (32% VRE, 1.5% MRSA and 16% MDRGN), with 25 patients also meeting the criteria for MDR infection. 70.9% of the 206 patients were successfully weaned from IMV, 8.7% died. In 72.2% of cases, nosocomial pneumonia and other infections were the main cause of death. Patients with evidence of MDR (infection and colonisation) had a higher incidence of weaning failure than those without evidence of MDR (48% vs. 34.8% vs. 21.7%). In multivariate analyses, MDR infection (OR 4.9, p = 0.004) was an independent risk factor for weaning failure, along with male sex (OR 2.3, p = 0.025), Charlson Comorbidity Index (OR 1.2, p = 0.027), pH (OR 2.7, p < 0.001) and duration of IMV before admission (OR 1.01, p < 0.001). In addition, MDR infection was the only independent risk factor for death (category 3cII), (OR 6.66, p = 0.007). Conclusion: Patients with MDR infection are significantly more likely to die during the weaning process. There is an urgent need to develop non-antibiotic approaches for the prevention and treatment of MDR infections as well as clinical research on antibiotic stewardship in prolonged weaning as well as in ICUs. [ABSTRACT FROM AUTHOR]

The vaginal epithelial barrier, which integrates mechanical, immune, chemical, and microbial defenses, is pivotal in safeguarding against external pathogens and upholding the vaginal microecological equilibrium. Although the widely used metronidazole effectively curtails Gardnerella vaginalis, a key pathogen in bacterial vaginosis, it falls short in restoring the vaginal barrier or reducing recurrence rates. Our prior research highlighted Lactobacillus crispatus CCFM1339, a vaginally derived Lactobacillus strain, for its capacity to modulate the vaginal epithelial barrier. In cellular models, L. crispatus CCFM1339 fortified the integrity of the cellular monolayer, augmented cellular migration, and facilitated repair. Remarkably, in animal models, L. crispatus CCFM1339 substantially abated the secretion of the barrier disruption biomarker E-cadherin (from 101.45 to 82.90 pg/mL) and increased the anti-inflammatory cytokine IL-10 (35.18% vs. the model), consequently mitigating vaginal inflammation in mice. Immunological assays in vaginal tissues elucidated increased secretory IgA levels (from 405.56 to 740.62 ng/mL) and curtailed IL-17 gene expression. Moreover, L. crispatus CCFM1339 enhanced Lactobacilli abundance and attenuated Enterobacterium and Enterococcus within the vaginal microbiome, underscoring its potential in probiotic applications for vaginal barrier regulation. [ABSTRACT FROM AUTHOR]

In hospital environments, droplets generated by urination within shared toilets may represent a route of dissemination for bacteria such as vancomycin-resistant Enterococcus faecium (VREfm), which contributes significantly to the burden of hospital-acquired infections. We investigated the potential activity of a foam in preventing the generation of droplets containing Enterococcus spp. during urination. A uniform layer of foam was deposited in the inner walls and at the bottom of an experimental toilet contaminated with suspensions of Enterococcus strains (including a VREfm strain). Human urination was simulated, and colonies of Enterococcus were recovered through a toilet lid where agar plates had been placed. Results showed that the foam was able to suppress production of droplets containing Enterococcus spp. generated by a liquid hitting inner toilet walls. Conversely, Enterococcus colonies were recovered in absence of foam. Moreover, the foam did not show antibacterial activity. We propose a new non-antimicrobial approach aimed at limiting transmission of multidrug-resistant bacteria, particularly in healthcare settings. [ABSTRACT FROM AUTHOR]

Aim The poultry industry represents an important economic sector in Tunisia. This study aims to determine the antimicrobial resistance phenotypes and genotypes and virulence factors of enterococci collected from chicken caecum in Tunisia. Methods and results Forty-nine composite chicken caecum samples were recovered in 49 different Tunisian farms (December 2019–March 2020). Each composite sample corresponds to six individual caecum from each farm. Composite samples were plated on Slanetz–Bartley agar both supplemented (SB-Van) and not supplemented (SB) with vancomycin and isolates were identified by matrix-assisted laser desorption/ionization time-of-flight. Antibiotic resistance and virulence genes were tested by Polymerase Chain Reaction (PCR) and sequencing and multilocus-sequence-typing of selected enterococci was performed. One hundred sixty seven enterococci of six different species were recovered. Acquired linezolid resistance was detected in 6 enterococci of 4/49 samples (8.1%): (A) four optr A-carrying Enterococcus faecalis isolates assigned to ST792, ST478, and ST968 lineages; (B) two poxt A-carrying Enterococcus faecium assigned to ST2315 and new ST2330. Plasmid typing highlighted the presence of the rep 10, rep 14, rep 7, rep 8, and pLG1 in these strains. One vancomycin-resistant E. faecium isolate (typed as ST1091) with van A gene (included in Tn 1546) was detected in SB-Van plates. The gelE, agg, esp , and hyl virulence genes were found in linezolid- and vancomycin-resistant enterococci. High resistance rates were identified in the enterococci recovered in SB plates: tetracycline [74.8%, tet (M) and tet (L) genes], erythromycin [65.9%, erm (B)], and gentamicin [37.1%, aac(6′)-Ie–aph(2″)-Ia ]. Conclusion The detection of emerging mechanisms of resistance related to linezolid and vancomycin in the fecal enterococci of poultry farms has public health implications, and further surveillance should be carried out to control their dissemination by the food chain. [ABSTRACT FROM AUTHOR]

Background: Enterococcus faecalis is a common cause of healthcare-associated infections. Its resistance to linezolid, the antibiotic of last resort for vancomycin-resistant enterococci, has become a growing threat in healthcare settings. Methods: We analyzed the data of E. faecalis isolates from 26 medical institutions between 2018 and 2020 and performed univariate and multivariate logistic regression analyses to determine the independent predictors for linezolid-resistant E. faecalis (LREFs). Then, we used the artificial neural network (ANN) and logistic regression (LR) to build a prediction model for linezolid resistance and performed a performance evaluation and comparison. Results: Of 12,089 E. faecalis strains, 755 (6.25%) were resistant to linezolid. Among vancomycin-resistant E. faecalis, the linezolid-resistant rate was 24.44%, higher than that of vancomycin-susceptible E. faecalis (p < 0.0001). Univariate and multivariate regression analyses showed that gender, age, specimen type, length of stay before culture, season, region, GDP (gross domestic product), number of beds, and hospital level were predictors of linezolid resistance. Both the ANN and LR models constructed in the study performed well in predicting linezolid resistance in E. faecalis, with AUCs of 0.754 and 0.741 in the validation set, respectively. However, synthetic minority oversampling technique (SMOTE) did not improve the prediction ability of the models. Conclusion: E. faecalis linezolid-resistant rates varied by specimen site, geographic region, GDP level, facility level, and the number of beds. At the same time, community-acquired E. faecalis with linezolid resistance should be monitored closely. We can use the prediction model to guide clinical medication and take timely prevention and control measures. [ABSTRACT FROM AUTHOR]

Drug resistance represents one of the great plagues of our time worldwide. This largely limits the treatment of common infections and requires the development of new antibiotics or other alternative approaches. Noteworthy, the indiscriminate use of antibiotics is mostly responsible for the selection of mutations that confer drug resistance to microbes. In this regard, recently, ozone has been raising interest for its unique biological properties when dissolved in natural oils. Ozonated oils have been reported to act in a non-specific way on microorganisms hindering the acquisition of advantageous mutations that result in resistance. Here, we focused on the antimicrobial effect of two commercial olive (OOO) and sunflower seeds (OSO) oils. Nuclear magnetic resonance spectroscopy and thermal analysis showed the change in the chemical composition of the oils after ozonation treatment. Different ozonated oil concentrations were then used to evaluate their antimicrobial profile against Candida albicans, Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Escherichia coli by agar diffusion and broth dilution methods. Cytotoxicity was also evaluated in keratinocytes and epithelial cells. Overall, our results revealed that both OOO and OSO showed a potent microbicidal effect, especially against C. albicans (IC50 = OOO: 0.3 mg/mL and OSO: 0.2 mg/mL) and E. faecalis (IC50 = OOO: 0.4 mg/mL and OSO: 2.8 mg/mL) albeit exerting a certain effect also against S. aureus and E. coli. Moreover, both OOO and OSO do not yield any relevant cytotoxic effect at the active concentrations in both cell lines. This indicates that the ozonated oils studied are not toxic for mammalian cells despite exerting a potent antimicrobial effect on specific microorganisms. Therefore, OOO and OSO may be considered to integrate standard therapies in the treatment of common infections, likely overcoming drug resistance issues. [ABSTRACT FROM AUTHOR]