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The overall theme of this dissertation is the application of mass spectrometry approaches to investigate infectious diseases. Chapter 1 contains background information regarding host-pathogen interactions, importance of clinical samples, and advances in mass spectrometry sample preparation, database curation, and data analysis techniques that familiarize the reader with the tools used during these studies. The following chapters describe primary author works completed by the author of this dissertation.Chapter 2 describes the discovery and characterization of microproteins produced by Staphylococcus aureus. The microproteins were discovered using a peptidogenomic approach and further validated with in-vitro and in-vivo assays. One of the novel microproteins is chemically and structurally similar to previously described virulence factors but appears to have a distinct mechanism of action. The other novel microprotein drives a dissociation phenotype reminiscent of exfoliative toxins. Elucidating the structural and biophysical mechanisms driving the interplay of these microproteins may provide a deeper understanding of host-pathogen interaction.Chapter 3 describes the application of multi-omics approaches to differentiate two similarly presenting enterococcal bacteremia subtypes and provides a global level view of the host immune and metabolic dysregulation. Using high resolution proteomics and metabolomics profiling of clinical serum samples we define a panel of over twenty biomarkers for further validation while also providing a number of targets of clinical importance.

Breast milk feeding is an important late-onset sepsis reduction strategy in the Neonatal Intensive Care Unit (NICU). However, multiple studies have reported transfer of bacteria-contaminated breast milk to infants. We describe a case of culture-positive breast milk resulting in persistent Enterococcus bacteremia in an infant. Beyond the development of an infant’s innate and specific immunity as well as colonization of the gastrointestinal (GI) tract with commensal organisms, the risk of bacterial translocation from the GI tract into the bloodstream is shaped and modified by maternal health, birth history, and an infant’s NICU course. While freezing and/or pasteurizing breast milk reduces or eliminates its bacterial load, it also diminishes its immunologic and nutritional benefits.

Objectives This study aimed to investigate the faecal carriage of enterococci harbouring oxazolidinone resistance genes among healthy humans in Switzerland and to genetically characterize the isolates. Methods A total of 399 stool samples from healthy individuals employed in different food-processing plants were cultured on a selective medium containing 10 mg/L florfenicol. Resulting enterococci were screened by PCR for the presence of cfr, optrA and poxtA. A hybrid approach combining short-read and long-read WGS was used to analyse the genetic context of the cfr, optrA and poxtA genes. Results Enterococcus faecalis (n = 6), Enterococcus faecium (n = 6), Enterococcus gallinarum (n = 1) and Enterococcus hirae (n = 2) were detected in 15/399 (3.8%) of the faecal samples. They carried cfr + poxtA, optrA, optrA + poxtA or poxtA. Four E. faecalis harbouring optrA and one E. faecium carrying poxtA were resistant to linezolid (8 mg/L). In most optrA-positive isolates, the genetic environments of optrA were highly variable, but often resembled previously described platforms. In most poxtA-positive isolates, the poxtA gene was flanked on both sides by IS1216E elements and located on medium-sized plasmids. Conclusions Faecal carriage of Enterococcus spp. harbouring cfr, optrA and poxtA in healthy humans associated with the food-production industry demonstrates the possibility of spread of oxazolidinone resistance genes into the community. Given the importance of linezolid as a last-resort antibiotic for the treatment of serious infections caused by Gram-positive pathogens, the detection of the oxazolidinone resistance determinants in enterococci from healthy humans is of concern for public health.

Aims This study aimed to investigate the physiological responses of two gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and two gram-positive bacteria (Enterococcus faecalis and Bacillus sphaericus) to ultraviolet (UV) and chlorine disinfection. Methods and Results Bacterial inactivation by UV and chlorine disinfection were evaluated with a plate count method for culturability, FCM and PMA-qPCR for membrane integrity and DyeTox13-qPCR for enzymatic activity, respectively. Both UV and chorine disinfection caused complete loss of culturability while membrane integrity remained intact after UV disinfection. Both DyeTox13-qPCR and PMA-qPCR showed high ΔCt values up to 8.9 after chlorine disinfection, indicating that both methods were able to distinguish non-treated from chlorine-treated cells. Although PMA-qPCR could not differentiate membrane integrity of cells on UV exposure, DyeTox13-qPCR showed significant differences in ΔCt values of 5.05 and 10.4 for gram-negative (E. coli) and gram-positive (Enterococcus) bacteria, respectively. However, DyeTox13-qPCR for gram-negative bacteria displayed relatively small differences in ΔCt values compared with gram-positive bacteria. Conclusion UV and chlorine disinfection led to changes in physiological state of gram-negative and gram-positive bacteria. Particularly, UV disinfection could induce active but non-culturable (ABNC) for gram-negative bacteria and dormant cell for gram-positive bacteria where intact cells no longer showed the enzymatic activity. Significance and Impact of the Study UV and chlorine are commonly used to disinfect water, food and fomites to inactivate pathogenic bacteria. However, a viable but non-culturable (VBNC) state of bacteria induced by disinfection may underestimate the health risks because of the potential resuscitation of VBNC cells. This study highlighted that bacteria could undergo different physiological (ABNC or dormant) states during UV and chlorine disinfection. In addition, viability PCR techniques could provide insight into the changes in physiological states during disinfection processes.

To compare deep infection rate and causative organisms in open fractures of the lower extremity from agricultural trauma with similar injuries in nonagricultural trauma.Retrospective.Two tertiary care institutions.Open lower extremity fractures sustained between 2003 and 2018 caused by agriculture-related trauma in adult patients were reviewed. A nonagriculture open fracture control group (NAG) was identified for comparison. Patient demographics and injury characteristics were assessed. Outcomes included occurrence of deep infection and causative organisms.One hundred seventy-eight patients were identified in the agriculture (AG) (n = 89) and control (NAG) (n = 89) groups. Among patients with agricultural injury, farm machinery was the most common mechanism in 69 (77.5%) of them. Open injuries of the foot (38.2%) and tibial shaft injuries (25.8%) were the most common in the AG and NAG groups, respectively. Deep infection was seen in 21% of patients in the AG group compared with 10% in the NAG group (P0.05). In the AG group, anaerobic infection occurred in 44% of patients with deep infection compared with 9.1% in the NAG group (P0.05). The most common anaerobic organisms included enterococci, Pseudomonas aeruginosa, and Clostridium perfringens.This study supports that open fractures due to agricultural trauma have a high infection rate, with anaerobic infection occurring at higher rates than in injuries due to nonagricultural trauma. Prophylactic treatment with antibiotics directed against anaerobes is indicated in these injuries.Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Patients with vancomycin-resistant Enterococcus (VRE) colonization should be managed in an isolation room with contact precautions. We herein report a patient whose colorectal carriage of VRE was successfully decolonized using concomitant bowel irrigation with polyethylene glycol, probiotics, and oral antimicrobials, linezolid and orally-administered daptomycin, for release from isolation and contact precautions. We therefore would like to suggest a potential strategy for managing patients with VRE colonization.

Background The treatment of polymicrobial periprosthetic joint infection (PJI) confronted distinct challenges. No reports have assessed the efficacy of local antibiotic delivery combined with 1-stage exchange in polymicrobial PJI. Methods Between January 2013 and December 2018, we retrospectively analyzed the data of 126 patients, including 19 polymicrobial PJIs and 107 monomicrobial PJIs, who underwent single-stage revision using intra-articular antibiotic infusion. The risk factors, microbiology, infection control rate, and clinical outcomes were compared between the 2 groups. Results Higher body mass index, presence of a sinus tract, and prior revisions were the risk factors for polymicrobial PJI. Isolation of Staphylococcus epidermidis, Streptococcus, Enterococcus, and Gram-negative pathogens was highly associated with polymicrobial PJI. Of the 19 polymicrobial PJIs, only 2 patients occurred infection recurrence, which is similar with the result of 6 of 107 patients in the monomicrobial PJI (P = .225). The Harris Hip Score of the polymicrobial group showed no difference from that of the monomicrobial group (78 vs 80; P = .181). Nevertheless, the polymicrobial group exhibited inferior Hospital for Special Surgery knee score relative to the monomicrobial group (77 vs 79; P = .017). Conclusion With rational and targeted use of antibiotics, single-stage revision can effectively control polymicrobial infections, and achieve favorable outcomes similar to that in monomicrobial patients. However, this regimen is still needed to be further confirmed, especially in the infections with different microbial species simultaneously. Additionally, obese patients with a sinus tract and those who had prior revisions had a greater risk of polymicrobial PJI.

Lactic Acid Bacteria being a reservoir of antimicrobial resistant genes, possibly pose a menace to human and animal health. Therefore, the purpose of this study was to assess the Horizontal Gene Transfer (HGT) of Macrolide-Lincosamide-Streptogramin (MLS) resistance from Lactic Acid Bacterial isolates of idli batter, chicken and sheep intestine viz., Lactobacillus fermentum (I4.16), Enterococcus hairae (C2C) and Enterococcus faecalis (SH7aab) respectively. These isolates being multidrug resistant were used as donor to analyse its transferability of MLS resistant gene to recipients Enterococcus faecalis JH2-2, Lactococcus lactis (T3.11) and Acinetobacter. Among the conjugation protocol used in the study, filter-mating method showed the efficient transfer frequency to obtain transconjugants. For all the conjugation the transconjugants obtained showed the acquisition of MLS resistance. The transfer frequency per recipient ranged between 1.4 × 10−4 to 3.7 × 10−5. The Minimum Inhibitory Concentration of erythromycin and clindamycin increased to 3–4 folds in the recipients after respective conjugation. Altogether, the results procured in this study indicates that the HGT between bacterial strains of food materials develop a vibrant gene pool that confers antibiotic resistance onto native gut microbiota even in the lack of pathogens. This probability of HGT among microbial pool should be considered as a criterion when Lactic Acid Bacteria are screened as starter cultures and probiotics in food industries.

Much evidence suggests a role for human milk oligosaccharides (HMOs) in establishing the infant microbiota in the large intestine, but the response of particular bacteria to individual HMOs is not well known. Here twelve bacterial strains belonging to the genera Bifidobacterium, Enterococcus, Limosilactobacillus, Lactobacillus, Lacticaseibacillus, Staphylococcus and Streptococcus were isolated from infant faeces and their growth was analyzed in the presence of the major HMOs, 2'-fucosyllactose (2'FL), 3-fucosyllactose (3FL), 2',3-difucosyllactose (DFL), lacto-N-tetraose (LNT) and lacto-N-neo-tetraose (LNnT), present in human milk. Only the isolated Bifidobacterium strains demonstrated the capability to utilize these HMOs as carbon sources. Bifidobacterium infantis Y538 efficiently consumed all tested HMOs. Contrarily, Bifidobacterium dentium strains Y510 and Y521 just metabolized LNT and LNnT. Both tetra-saccharides are hydrolyzed into galactose and lacto-N-triose (LNTII) by B. dentium. Interestingly, this species consumed only the galactose moiety during growth on LNT or LNnT, and excreted the LNTII moiety. Two β-galactosidases were characterized from B. dentium Y510, Bdg42A showed the highest activity towards LNT, hydrolyzing it into galactose and LNTII, and Bdg2A towards lactose, degrading efficiently also 6'-galactopyranosyl-N-acetylglucosamine, N-acetyl-lactosamine and LNnT. The work presented here supports the hypothesis that HMOs are mainly metabolized by Bifidobacterium species in the infant gut., This work is part of the Grants AGL2017-84165-C2 (1-R and 2-R) and PID2020-115403RB (C21 and C22) funded by the Spanish Ministry of Science and Innovation (MICIN)/Spanish State Research Agency (AEI)/10.13039/501100011033, and by "ERDF A way of making Europe".

Hurricane-caused stormwater runoffs transport diverse terrestrial pollutants, adversely impact microbiological water quality, and introduce fecal and other pathogens to coastal water environments. This study investigated the genotypic diversity, phylogenetic composition, antibiotic resistance patterns, and virulence gene repertoire of the Enterococcus population in the Hilo Bay coastal water after the immediate impact of Hurricane Lane. DNA fingerprinting of Enterococcus isolates exhibited large genotypic diversity, while 16S rRNA gene sequencing identified four major species, including E. faecalis (34.7%), E. faecium (22.4%), E. hirae (22.4%), and E. durans (18.4%). Four common enterococcal virulence genes (cylA, esp, asa1, and gelE) were detected in the Enterococcus population, with significant portions of E. durans (33.3%), E. faecalis (41.2%), E. faecium (36.4%), and E. hirae (27.3%) isolates possessing two or more virulence genes. Considerable antibiotic resistance to rifampin, erythromycin, tetracycline, and nitrofurantoin was detected in the Enterococcus population, with one E. durans isolate showing vancomycin resistance. The results indicate considerable health implications associated with Enterococcus spp. in the hurricane-impacted tropical coastal water, illustrating the needs for more comprehensive understanding of the microbiological risks associated with storm-impacted coastal water. HIGHLIGHTS The study investigated the Enterococcus population in a tropical coastal water immediately after the impact of a major hurricane.; Genotypic diversity and phylogenetic composition of the Enterococcus population were determined.; A significant portion of the Enterococcus population contains various virulence factors.; Considerable antibiotic resistance was detected in the Enterococcus population.

Recently, among hospital strains of microorganisms, an increase in the number of antiseptic-resistant strains of opportunistic pathogens has been registered, which significantly affects the effectiveness of these drugs. It is important to study their antimicrobial efficacy to justify rational use. The aim is to conduct a comparative study of the antimicrobial efficacy of antiseptics of decamethoxine, chlorhexidine, polyhexanide. During study we examined the antimicrobial activity against 186 clinical strains of microorganisms (Acinetobacter baumannii, Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus spp., Enterobacter spp.) isolated from patients with infectious complications in the postoperative period. The minimum inhibitory (MIC) and bactericidal concentrations (MBC) of 0.02 % and 0.1 % decamethoxine, 0.05 % chlorhexidine bigluconate, 0.1 % polyhexanide were determined; antimicrobial efficacy of drugs was evaluated by the index of antiseptic activity by conventional methods. The study found high antimicrobial properties of decamethoxine, chlorhexidine, which had a high bactericidal effect on clinical strains of S. aureus, Enterococcus spp., Enterobacter spp. Proved the benefits of antimicrobial activity of the drug based on decamethoxine (p

The co-occurrence of heavy metals, antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) from hospital effluents spreading into the river receiving systems and evaluating associated risks are topics of scientific interest and still under-studied in developing countries under tropical conditions. To understand the selectors of the ARGs, we examined the occurrence of heavy metals (Cr, Co, Ni, Cu, Cd, Pb and Zn), associated ARB (β-lactam-resistant Escherichia coli, β-lactam-resistant Enterobacteriaceae, and carbapenem-resistant Enterobacteriaceae) and ARGs (blaOXA, blaCTX-M, blaIMP, blaTEM) in water and sediments from two sub-urban rivers receiving urban and hospital effluent waters in the Democratic Republic of the Congo (DRC). High abundances of ARB and ARGs were observed in all sediment samples. All the metal contents correlated negatively with grain size (− 0.94 ≤ r ≤ − 0.54, p r ≤ 0.79, p Enterococcus except for Ni and Cd (0.43 ≤ r ≤ 0.67, p r = − 0.44, p r ≤ 1.0, p

The aim of the work is to evaluate ability of gentian violet and malachite green to inhibit 2 Brucella test strains and 8 strains of unwanted organisms and the influence of autoclaving on their activity. The study also aims to evaluate variability of inhibition in different batches of colorants and necessity in adjustment of their concentration.Materials and methods. The study included 3 imported lots of gentian violet and malachite green. Inhibitors were put into nutrient medium containing pancreatic hydrolysates of gelatin and fsh meal, yeast extract, sodium chloride, glucose, sodium pyrosulfate, and agar. The same medium without colorants was used as a control medium. Effect of the colorants was studied with the help of test strains of Brucella abortus 19 ВА, B. melitensis Rev I, Enterococcus faecium VKM B-602, Escherichia coli ATCC 25922, Proteus vulgaris HX 19 222, Pseudomonas aeruginosa 22/99, Serracia plymuthica 1, Shigella flexneri 1a 8516, Staphylococcus aureus ATCC 25923, Yersinia enterocolitica C-187.Results and discussion. We have determined biological parameters of nutrient media containing gentian violet (5,0; 2,5 1,25 mg/L) and malachite green (2.0; 1.0; 0.5 mg/L) when cultivating brucella. Gentian violet is able to inhibit Brucella greatly at concentration of 5 mg/L. S. aureus ATCC 25923 did not show any growth on the media containing malachite green or gential violet (5.0 and 2.5 mg/L). Malachite green inhibited the growth of enterococcus more actively than gentian violet. However, it inhibited swarming growth of Proteus less successfully than gentian violet. Other unwanted organisms were not sensitive to such concentrations of colorants at all. We have demonstrated the necessity to combine colorants with other selective agents, as well as advisability to put gentian violet into sterile media, while malachite green – into the media before its autoclaving. Adjustments to the concentration of gentian violet should be made when producing nutrient medium, as variations in inhibiting activity in different batches of this colorant were revealed.

To assess the value of procalcitonin (PCT) as an early biomarker for predicting urosepsis caused by Gram-negative (GN) bacteria, Gram-positive (GP) bacteria and fungi following mini-percutaneous nephrolithotomy (mPCNL) and flexible ureteroscopy (FURS).A total number of 356 patients with positive preoperative UC (urine cultures) who underwent mPCNL and FURS between June 2017 and January 2021 were retrospectively analyzed. Univariable analysis and multivariable logistic regression analysis were conducted to compare the predictors for urosepsis caused by different organisms. Furthermore, the nomogram was established as a predicted model for urosepsis.Among 356 positive UC, 265 (74.4%) were positive for GN bacteria, 77 (21.4%) for GP bacteria and 14 (3.9%) for fungal pathogens. Escherichia coli (48.9%) were the predominant pathogens and Enterococcus (54/77) were the most common GP bacteria. Multivariate logistic regression analysis showed that positive nitrite (OR 3.31, 95% CI 1.20-9.14; P = 0.021), operative time 90 min (OR 3.10, 95% CI 1.10-8.75, P = 0.033) and postoperative PCT 0.1 ng/mL (OR 56.18, 95% CI 15.20-207.64, P 0.001) were associated with postoperative urosepsis originated in GN infections, while urosepsis caused by GP bacteria and fungi was not associated with PCT 0.1 ng/mL (P = 0.198), only stone burden 800 mmFor patients with positive preoperative UC, postoperative PCT 0.1 ng/mL was an independent risk factor of post-PCNL and post-FURS urosepsis caused by GN bacteria rather than GP bacteria and fungi.

Background A major focus of research on the gut microbiota of poultry has been to define signatures of a healthy gut and identify microbiota components that correlate with feed conversion. However, there is a high variation in individual gut microbiota profiles and their association with performance. Population level samples such as dust and pooled excreta could be useful to investigate bacterial signatures associated with productivity at the flock-level. This study was designed to investigate the bacterial signatures of high and low-performing commercial meat chicken farms in dust and pooled excreta samples. Poultry house dust and fresh pooled excreta were collected at days 7, 14, 21, 28 and 35 of age from 8 farms of two Australian integrator companies and 389 samples assessed by 16S ribosomal RNA gene amplicon sequencing. The farms were ranked as low (n = 4) or high performers (n = 4) based on feed conversion rate corrected by body weight. Results Permutational analysis of variance based on Bray–Curtis dissimilarities using abundance data for bacterial community structure results showed that company explained the highest variation in the bacterial community structure in excreta (R2 = 0.21, p = 0.001) while age explained the highest variation in the bacterial community structure in dust (R2 = 0.13, p = 0.001). Farm performance explained the least variation in the bacterial community structure in both dust (R2 = 0.03, p = 0.001) and excreta (R2 = 0.01, p = 0.001) samples. However, specific bacterial taxa were found to be associated with high and low performance in both dust and excreta. The bacteria taxa associated with high-performing farms in dust or excreta found in this study were Enterococcus and Candidatus Arthromitus whereas bacterial taxa associated with low-performing farms included Nocardia, Lapillococcus, Brachybacterium, Ruania, Dietzia, Brevibacterium, Jeotgalicoccus, Corynebacterium and Aerococcus. Conclusions Dust and excreta could be useful for investigating bacterial signatures associated with high and low performance in commercial poultry farms. Further studies on a larger number of farms are needed to determine if the bacterial signatures found in this study are reproducible.

Background Pharmacokinetic-pharmacodynamic (PK/PD) targets of vancomycin therapy have been recognized for methicillin-resistant Staphylococcus aureus infections but not for other gram-positive bacterial infections. Therefore, we investigated whether vancomycin concentration targets such as the trough level and ratio of the area under the curve to minimum inhibitory concentration (AUC/MIC) are associated with the treatment outcome in enterococcal bacteremia. Methods A retrospective cohort analysis enrolled patients with bacteremia caused by vancomycin-susceptible Enterococcus faecium and Enterococcus faecalis who were treated with vancomycin from January 2007 to December 2017 at a tertiary hospital located in Seoul, South Korea. Patients without vancomycin concentrations were excluded from the study. The primary outcome was 28-day all-cause mortality. Results A total of 37 patients were enrolled—26 with E. faecium infection and 11 with E. faecalis infection. The 28-day all-cause mortality rate was 21.6 %. In univariate analysis, vancomycin trough level (≤ 15 µg/mL; p = 0.042), age (p = 0.044), and septic shock (p = 0.049) were associated with 28-day mortality but not AUC24/MIC (> 389; p = 0.479). In multivariate analysis, vancomycin trough concentration (≤ 15 µg/mL; p = 0.041) and younger age (p = 0.031) were associated with 28-day mortality in patients with enterococcal bacteremia. Conclusions In this study, a vancomycin trough level of 15 µg/mL or lower was associated with 28-day mortality in enterococcal bacteremia. However, relatively large prospective studies are needed to examine the efficacy of vancomycin PK/PD parameters in patients with enterococcal bacteremia.

Antimicrobial resistance (AMR) is a major health crisis globally. Migratory birds could be a potential source for antibiotic resistant (ABR) bacteria. Not much is known about their role in the transmission of ABR in Bangladesh. In this study, a total of 66 freshly dropped fecal materials of migratory birds were analyzed. Bacterial isolation and identification were based on cultural properties, biochemical tests, and polymerase chain reaction (PCR). The disk diffusion method was employed to evaluate antibiogram profiles. By PCR, out of 66 samples, the detection rate of Enterococcus spp. (60.61%; 95% confidence interval: 48.55-71.50%) was found significantly higher than Salmonella spp. (21.21%; 95% CI: 13.08-32.51%) and Vibrio spp. (39.40%; 95% CI: 28.50-51.45%). Enterococcus isolates were frequently found resistant (100-40%) to ampicillin, streptomycin, meropenem, erythromycin, and gentamicin; Salmonella isolates were frequently resistant (72-43%) to chloramphenicol, tetracycline, ampicillin, streptomycin, and erythromycin; and Vibrio spp. isolates were frequently resistant (77-31%) to vancomycin, ampicillin, erythromycin, tetracycline, and streptomycin. In addition, 60% (95% CI: 44.60-73.65%) Enterococcus spp., 85.71% (95% CI: 60.06-97.46%) Salmonella spp., and 76.92% (95% CI: 57.95-88.97%) Vibrio spp. isolates were multi-drug resistant (MDR) in nature. Three isolates (one from each bacterium) were found resistant against six classes of antibiotics. The bivariate analysis revealed strong associations (both positive and negative) between several antibiotic pairs which were resistant to isolated organisms. To the best of our knowledge, this is the first study in detecting MDR Enterococcus spp., Salmonella spp., and Vibrio spp. from migratory birds travelling to Bangladesh. Frequent detection of MDR bacteria from migratory birds travelling to Bangladesh suggests that these birds have the potential to carry and spread ABR bacteria and could implicate potential risks to public health. We recommend that these birds should be kept under an AMR surveillance program to minimize the potential risk of contamination of the environment with ABR as well as to reduce their hazardous impacts on health.

Purpose. To evaluate the effectiveness of bacteriocin of Enterococcus italicusONU 547 and essential oils individually and in combination against indicatorstrains of opportunistic pathogens. Methods. The antagonistic activity of essential oils and bacteriocin was determined by the optical density of the bacterial suspension of test strains (Salmonella enterica NCTC 6017, Escherichia coli АТСС 25922, Pseudomonas aeruginosa АТСС 27853, Pseudomonas putida KT 2440, Enterococcus faecalis АТСС 29212, Klebsiella pneumoniae АТСС 10031,Staphylococcus aureus АТСС 25923). The index of fractional inhibitory activity(FIC) was calculated by adding the FIC values of bacteriocin E. italicus ONU 547and the studied essential oils. The results. The maximum antimicrobial effect was caused by the essential oils of Anisum officinalis and Melissa officinalis, which suppressed the growth of test strains more than 50.0%. When using bacteriocin of E. italicus ONU 547 suppression of viability of indicator strains did not exceed 30.0%. Experimental combinations of essential oils and bacteriocin caused 4 types of consequences: synergy effect; additive effect; antagonistic effect; interactiveeffect (no interaction effect). In most cases, the combined action of bacteriocinand essential oils caused an additive effect. Conclusions. This study demonstrated the potential of using different combinations of natural antimicrobial compounds. The obtained results provide grounds for further development and optimization ofcombinations of essential oils and probiotic strains of microorganisms for use in food and pharmaceutical biotechnology.

Background and Rationale: Enterococci have long been recognised as low virulence bacteria occurring as commensals in the human intestine. However in the last two decades they emerged as one of the leading causes of nosocomial infections with the development of resistance to antibiotics. So appropriate identification and characterization and antimicrobial susceptibility testing of Enterococcal species is necessary for management and prevention of these infections. Materials and Methods: 150 isolates of Enterococcal species were obtained from various clinical samples. Characterisation was done by standard Microbiological methods and antibiotic susceptibility testing was done by Kirby- Bauer disc diffusion method and Vancomycin MIC tested by E- test. Results: Out of 150 isolates from various clinical samples like urine 93(62%), pus 45(30%), blood 7(4.6%) and other body fluids 5(3%), E.faecalis 131(87.3%) was the predominant isolate followed by E.faecium 14(9.3%), E.avium 2(1.3%), E.raffinosus 2(1.3%) and E.durans 1(0.6%). All isolates were sensitive to Vancomycin, Teicoplanin and Linezolid. Sensitivity to High level Gentamicin was 92%. Rate of resistance to Penicillin 150(100%), Tetracycline 95(63.3%), Ciprofloxacin 103(68.6%) and Ampicillin 67(44.6%). Conclusions: Even though no Vancomycin resistant strains were isolated from our study, there is incidence of Vancomycin resistant Enterococci are emerging as potent pathogen. So methods for characterization, antimicrobial susceptibility testing and MIC of Vancomycin should be done routinely for Enterococcal species. Keywords: Enterococcus, Efaecalis, Efaecium, High level Gentamicin, Vancomycinresistant Enterococci

Objective:We compared the rates of hospital-onset secondary bacterial infections in patients with coronavirus disease 2019 (COVID-19) with rates in patients with influenza and controls, and we investigated reports of increased incidence of Enterococcus infections in patients with COVID-19.Design:Retrospective cohort study.Setting:An academic quaternary-care hospital in San Francisco, California.Patients:Patients admitted between October 1, 2019, and October 1, 2020, with a positive SARS-CoV-2 PCR (N = 314) or influenza PCR (N = 82) within 2 weeks of admission were compared with inpatients without positive SARS-CoV-2 or influenza tests during the study period (N = 14,332).Methods:National Healthcare Safety Network definitions were used to identify infection-related ventilator-associated complications (IVACs), probable ventilator-associated pneumonia (PVAP), bloodstream infections (BSIs), and catheter-associated urinary tract infections (CAUTIs). A multiple logistic regression model was used to control for likely confounders.Results:COVID-19 patients had significantly higher rates of IVAC and PVAP compared to controls, with adjusted odds ratios of 4.7 (95% confidence interval [CI], 1.7–13.9) and 10.4 (95 % CI, 2.1–52.1), respectively. COVID-19 patients had higher incidence of BSI due to Enterococcus but not BSI generally, and whole-genome sequencing of Enterococcus isolates demonstrated that nosocomial transmission did not explain the increased rate. Subanalyses of patients admitted to the intensive care unit and patients who required mechanical ventilation revealed similar findings.Conclusions:COVID-19 is associated with an increased risk of IVAC, PVAP, and Enterococcus BSI compared with hospitalized controls, which is not fully explained by factors such as immunosuppressive treatments and duration of mechanical ventilation. The mechanism underlying increased rates of Enterococcus BSI in COVID-19 patients requires further investigation.

Introduction. Intestinal dysbiosis against the background of type 1 diabetes mellitus (DM) results in the development and unfavourable clinical course of chronic diseases, in particular of ENT-organs. Objective of the study — to investigate the species composition and population level of microflora of the large intestine in patients with DM type 1 depending on the disease duration and age of patients. Material and methods. With the use of modern bacteriological and mycological methods, we have studied species composition and population level of the microbiota of the large intestine in 50 patients with type 1 DM of the following age groups: 15–20 years (n = 10); 21–35 years (n = 14); 36–60 years (n = 26). Results. In patients with DM type 1, there occurs a significant deficiency of autochthonous anaerobic bifido- and lactobacteria in the contents of the large intestine. With the age of the patient, this deficiency increases, a clear picture of reducing the role of bifidobacteria in the large intestine microbiocenosis is being predicted. A similar situation is emerging in bacteria Lactobacillus, Peptostreptococcus and Enterococcus. There is an increase of the biological role in the microbiocenosis of bacteroides, pathogenic (E.coli Hly+, enteropathogenic E.coli) and opportunistic (Proteus, Enterobacter, Citrobacter) enterobacteria, clostridia, staphylococci and yeast-like fungi of the genus Candida. Conclusions. With age, there is an increase in the negative processes of changes in species composition and population level, constancy index, Berger-Parker dominance, detection rate, coefficient of quantification dominance and importance. There occurs a deficiency and reduction in the role in microbiocenosis of bacteria of the genus Bifidobacterium, Lactobacillus, Peptostreptococcus and bacteria of the genus Enterococcus.

The black soldier fly larvae (BSFL) have been successfully applied to treat various organic wastes. However, the impacts of heavy metals on antibiotic resistance in the BSFL guts are poorly understood. Here, we investigated the effect of copper (exposure concentrations of 0, 100 and 800 mg/kg) on the antibiotic and metal resistance profiles in BSFL guts. A total of 83 antibiotic resistance genes (ARGs), 18 mobile genetic elements (MGEs) and 6 metal resistance genes (MRGs) were observed in larval gut samples. Exposure to Cu remarkably reduced the diversity of ARGs and MGEs, but significantly enhanced the abundances of gut-associated ARGs and MRGs. The levels of MRGs copA, czcA and pbrT were dramatically strengthened after Cu exposure as compared with CK (increased by 2.8–13.5 times). Genera Enterococcus acted as the most predominant potential host of multiple ARG, MGE and MRG subtypes. Meanwhile, high exposure to Cu aggravated the enrichment of potential pathogens in BSFL guts, especially for Escherichia, Enterococcus and Salmonella species. The mantel test and procrustes analysis revealed that the gut microbial communities could be a key determinant for antibiotic and metal resistance. However, no significant positive links were observed between MGEs and ARGs or MRGs, possibly suggesting that MGEs did not play a crucial role in shaping the ARGs or MRGs in BSFL guts under the stress of Cu. These findings extend our understanding on the impact of heavy metals on the gut-associated antibiotic and metal resistome of BSFL.

Urinary tract infection (UTI) is a prevalent disease among children. This study is an attempt to find the bacterial agents of UTI and antibiotic resistance in children. A descriptive cross-sectional study was carried out on 1316 clinical samples of children at Abuzar Hospital in Ahvaz that had positive urine culture. The strains were determined through biochemical tests and differential culture media. The pattern of antibiotic resistance of the studied strains was determined by the disk diffusion method. Out of the 1316 children surveyed, 821 were girls and 495 were boys. The most isolated strains from urine cultures were Escherichia coli (57.52%) followed by Enterococcus (12.15%). E. coli isolates demonstrated the highest resistance to ampicillin (57.06%) and amikacin was recognized as the most effective antibiotic with a sensitivity of 91.94%. E. coli was the most common causative agent of UTI in children. Amikacin was recognized as the appropriate choice against urinary tract pathogens. Because, in different regions and over time, the frequency distribution of antibiotic resistance varies, it is recommended to carry out periodic monitoring of antibiotic resistance for infection control.

Aim: To focus on the frequency of ICU-acquired infections in Sars Co-V2 Corona Virus disease (COVID 19) patients. Method: A retrospective observational study carried out in two tertiary care hospitals treating COVID 19 cases, Services Institute of Medical Sciences and Bahria International Hospital, Lahore. Data was collected from the medical records of the COVID 19 ICUs of both hospitals from May 1, 2020 to April30, 2021. All charts were reviewed for the evidence of positive cultures. The treatment given prior to positive cultures, after the availability of culture results and outcomes were also recorded. Results: A total of 432 records were reviewed and 400 cases were included while 32 cases were excluded because of incomplete data. The frequency of infections per 1,000 days of ICU stay was calculated in 90 (22.5%) patients. Gram-negative bacteria accounted for 68 cases (75.5%) with Pseudomonas in 44 cases (48.8%), Acinetobacter in 23/90 (25.5%) while 17 cases (18.8%) had gram positive infection with Enterococcus in 14/18 (77.77%) or 14/90 (15.55%), MRSA in 4/18 (22.22%) 4/90 (4.44%), while 5/90 (5.5%) had more than 2 isolates at same time. Among these 3 had both pseudomonas and Acinetobacter while 2 patients had Pseudomonas and Stenotrophomonas Maltophilia. Conclusion: There seems to be an increase in the infection rate among critically sick COVID 19 patients admitted in ICU. Use of steroids and Tocilizumab seems to play a role through their immunomodulatory effects. Keywords: Tocilizumab, Secondary infections

Sufu is a common solid-state traditional fermented food made from soybean. Huase sufu is a typical type found in several provinces of China, especially in Hubei. However, little is known about the bacterial community. High-throughput sequencing technology revealed that the dominant taxa at phylum level were: Firmicutes, Proteobacteria and Bacteroides, and at the genus level were: Pseudomonas, Lactococcus, Acinetobacter, etc. Additionally, LEfSe revealed that compared with the bacterial community of red sufu and white sufu, the biomarker genera for both huase sufu were Enterococcus, and Myroides. Moreover, there were twenty-eight hubs for the huase sufu samples, and four of them were dominant genera: Citrobacter, Myroides, Vagococcus, and Enterococcus. These results provide a new insight into our understanding of the bacterial diversity of huase sufu, and will facilitate the isolation, screening, and development potential bacterial strains for production of huase sufu. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10068-021-00963-3.

AIMS The objective of this study was to isolate multifunctional bacteriocin-producing strains; to characterize the expressed bacteriocin for the control of Listeria monocytogenes and vancomycin-resistant Enterococcus; to evaluate the safety of studied strains; and to explore their antifungal activity. METHODS AND RESULTS Two Pediococcus strains were isolated from silage samples obtained from an organic farm in Belogradchik, Bulgaria. The strains were identified by 16S rRNA sequencing analysis and characterized as bacteriocins producers. Strong antimicrobial activity was detected against more than 74 different strains of Listeria monocytogenes, 27 different vancomycin-resistant Enterococcus strains. In addition, studied strains were able to inhibit the growth of strains of Alternaria alternate, Aspergillus flavus, Aspergillus niger, Cladosporium sphaerospermum, Penicillium chrysogenum and Penicillium expansum. Some aspects of the antimicrobial mode of action were evaluated, including killing curves and aggregation properties. Both strains generated positive PCR results for the presence of pediocin PA-1, but not for other bacteriocins evaluated in this screening process. Metabolomic analysis of the cell-free supernatants from both strains was performed in order to explain the observed antifungal activity against different moulds. According to PCA and PLS-DA score plot, P. acidilactici ST3522BG and P. pentosaceus ST3633BG were clearly clustered from control (MRS). Increases in the production of benzoic acid, 2-hydroxyisocaproic acid, β-phenyl-lactic acid, α-hydroxybutyric acid and 1,3-butanediol were recorded, these metabolites were previously described as antifungal. CONCLUSIONS Pediococcus acidilactici ST3522BG and P. pentosaceus ST3633BG were evaluated as producing bacteriocin strains with high specificity against Listeria and vancomycin-resistant Enterococcus species. In addition, both investigated Pediococcus strains were evaluated as producer of effective antifungal metabolites with potential for the inhibition of mycotoxin-producing moulds. SIGNIFICANCE AND IMPACT OF THE STUDY To the best of our knowledge, this report is a pioneer in the evaluation of Pediococcus strains isolated from silage with highly specific bacteriocinogenic antimicrobial activity against Listeria spp. and vancomycin-resistant Enterococcus spp., and antifungal activity against mycotoxin-producing moulds.

In this study, the antimicrobial effect of exopolysaccharide (EPS) extracted from Enterococcus strains [E. durans K48 (MT437,248), E. faecium R114 (MT437,249) and E. faecium T52 (MT437,250)] isolated from Kishk was applied against some foodborne pathogenic bacteria using well diffusion and microdilution methods. The antioxidant activity of EPS was also evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay and ferric reducing antioxidant power (FRAP) method. The cytotoxicity effect of EPS on human Gingival Fibroblast (HGF) cell line was also assessed. The results obtained by antimicrobial test showed that the most resistant bacteria to the examined EPS was Listeria monocytogenes, and the most susceptible were Staphylococcus aureus and E. faecalis. The results showed that the DPPH inhibitory percentage of EPS (25 mg/mL) from E. durans K48, E. faecium R114, and E. faecium T52 was 53%, 58% and 64%, respectively. EPS from E. faecium T52 displayed the highest reducing power, but statistically, there was no significant difference between the reducing power of EPS T52 and EPS R114 (P ≥ 0.05). The lowest toxicity percentage of EPS k48, EPS T52, and EPS R114 on normal human cell line at a concentration of 0.2 mg/mL was 10%, 15%, and 13%, respectively, which was statistically significant (P < 0.05). The obtained results in the present study indicate that EPS from the examined LAB strains with no in vitro cytotoxicity can be a potential source of natural antioxidant and antibacterial agent to be used in food and pharmaceutical industries., This work was financially supported by a Grant (No. 47333) from Ferdowsi University of Mashhad (Research affairs), Iran.

A survey is presented concerning original research articles published in well-reputed scientific journals on the isolation of lactic acid bacteria (LAB) from cheeses worldwide, where researchers evaluated the bacteriocin production by such isolates in searching for novel functional peptides that can exhibit potential for biotechnological applications. Seventy-one articles were published in the period of study, with contributions being American (45%), Asiatic (28%), and European (21%), being Brazil-USA-Mexico, Turkey-China, and France-Italy the countries that contributed the most for each said continent, respectively. Most of the isolated LAB belong to the genera Enterococcus (35%), Lactobacillus (30%), Lactococcus (14%), and Pediococcus (10%), coming from soft (64%), hard (27%), and semi-hard (9%) cheeses, predominantly. Also, scholars focused mainly on the food biopreservation (81%) and pharmaceutical field (18%) potential applications.

Background The impact of enterococci in human health has been growing for the last decades, mainly due to their resistance to several antimicrobial agents. Human consumption of contaminated meat, especially poultry, has been identified as a possible route of transmission. The aim of the present study was to evaluate and compare the antimicrobial resistance profiles and virulence genes of enterococci isolated from Portuguese conventional and free-range broiler farms. Results Antibiotic susceptibility testing showed high frequencies of resistance to tetracycline in both farming systems. Resistance to erythromycin and gentamicin were detected in about half of the isolates. Resistance to penicillin was the less frequently observed and no vancomycin resistant isolates were identified. The majority of the enterococcal isolates, from either farming systems, were resistant to more than one antibiotic, and no statistical associations were found, except for penicillin resistance which associated with the genetic clusters. No differences were found between farming systems regarding the prevalence of tet(M), erm(B), aac (6′)-Ie-aph (2″)-Ia and pbp5 genes, nevertheless pbp5 prevalence was associated with the different genetic clusters. Hemolytic activity was identified in 26.47% of all isolates and gelatinase activity in 50%. The gelE gene was identified in the majority of the isolates, whereas esp and agg genes were rarely detected. The cylA determinant was not detected in any of the isolates. Conclusions Overall, results suggest that similar resistance patterns and virulence genes can be found in both farming systems, though enterococci in free-range conditions should be less prone to acquire further resistance genes.

Background/aims Acute cholangitis (AC) is a potentially life-threatening bacterial infection, and timely antimicrobial treatment, faster than that achieved with bacterial cultures, is recommended. Although the current guidelines refer to empirical antimicrobial treatment, various kinds of antimicrobial agents have been cited because of insufficient analyses on the spectrum of pathogens in AC. Enterococcus spp. is one of the most frequently isolated Gram-positive bacteria from the bile of patients with AC, but its risk factors have not been extensively studied. This study aimed to analyze the risk factors of AC caused by Enterococcus faecalis and Enterococcus faecium. Methods Patients with AC who were hospitalized in a Japanese tertiary center between 2010 and 2015 were retrospectively analyzed. Patients' first AC episodes in the hospital were evaluated. Results A total of 266 patients with AC were identified. E. faecalis and/or E. faecium was isolated in 56 (21%) episodes of AC. Prior endoscopic sphincterotomy (EST), the presence of a biliary stent, prior cholecystectomy, and past intensive care unit admission were more frequently observed in AC patients with E. faecalis and/or E. faecium than in those without such bacteria. Prior EST was identified as an independent risk factor for AC caused by E. faecalis and/or E. faecium in the multivariate analysis. Conclusions Given the intrinsic resistance of E. faecalis and E. faecium to antibiotics, clinicians should consider empirical therapy with anti-enterococcal antibiotics for patients with prior EST.

Glycerol phosphate (GroP)-based teichoic acids (TAs) are antigenic cell-wall components found in both enterococcus and staphylococcus species. Their immunogenicity has been explored using both native and synthetic structures, but no details have yet been reported on the structural basis of their interaction with antibodies. This work represents the first case study in which a monoclonal antibody, generated against a synthetic TA, was developed and employed for molecular-level binding analysis using TA microarrays, ELISA, SPR- analyses, and STD-NMR spectroscopy. Our findings show that the number and the chirality of the GroP residues are crucial for interaction and that the sugar appendage contributes to the presentation of the backbone to the binding site of the antibody

Aim: This report highlights the use of doxycycline therapy other than the more standard regimen that includes an aminoglycoside in the management of enterococcal infection in patients with renal impairment without causing further damages to the kidney due to aminoglycoside therapy. Presentation of Case: A case of enteroccocal septicemia in a 29-year-old woman who was admitted on account of acute kidney injury secondary to pregnancy induced hypertension in the setting of pre-eclampsia. She was referred from another centre where she had emergency caesarean section done on account of severe pre-eclampsia at 36 weeks gestational age. Blood culture yielded Enterococcus species. When other antibiotic regimen failed, she was started on doxycycline. Patient had good clinical response and was discharged 7 days after commencement of doxycycline. Discussion: Enteroccoci have emerged as important agent of human disease largely because of their resistance to antimicrobial agents. They are important nosocomial pathogens capable of causing serious and potentially life-threatening infections, including sepsis. The incidence of enteroccocal infections, mainly hospital-acquired, has increased over the past 2 decades and isolates with novel mechanism of resistance to antimicrobial agents are more and more frequent. Furthermore, they have great capacity for transmitting these resistances to other species and even to other genera. Conclusion: Doxycycline is a safe and effective alternative antibiotic for the treatment of enterococcal sepsis in patients with impaired renal status.

Background and Aim: Wild birds raised in urban environments may be exposed to many negative factors, including biological and chemical toxic elements. The aim of the study was to assess the occurrence of bacteria and parasites in wild birds, based on the example of the peregrine falcon (Falco peregrinus) as a potential indicator of bacterial drug resistance genes. Toxicological contamination was also analyzed to determine the impact of urbanized areas on this predatory species, in terms of its health, welfare, and survival in urban environments. Materials and Methods: The samples consisted of down feathers and fresh feces obtained from seven falcon chicks (during obligatory veterinary examination) reared in two nests located in the Lublin region (Lublin and Pulawy). Bacteria and parasites were isolated directly from feces by classical microbiological methods, polymerase chain reaction, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MS). The down feathers and feces of birds were used for toxicological testing by plasma inductively coupled plasma MS to assess the concentrations of selected heavy metals (cadmium [Cd], lead [Pb], arsenic [As], zinc [Zn], and copper [Cu]). Results: The study revealed the presence of a diverse microbiome in the falcon chicks, among which Escherichia coli, Enterococcus spp., and Staphylococcus spp. bacteria and parasites of the genus Caryospora were dominant. The presence of drug resistance genes was also confirmed among the pathogens. The toxicological analysis found high concentrations of toxic heavy metals, including Cd, Pb, As, and Zn, in the downy feathers and feces of peregrine chicks. Conclusion: Predatory free-living birds living in urban environments not only can be infected with various pathogens but may also show contamination with heavy metals, which could influence their natural resistance, condition, and welfare.

We assessed the prevalence, distribution, and antibiotic resistance patterns of Escherichia coli and Enterococcus spp. isolated from raw and treated wastewater of a major wastewater treatment plant...

–: The present study investigated the phylogeny based on 16S rRNA gene sequences of psychrotrophic bacteria isolated from refrigerated raw cow milk collected in an arid area of Algeria. During cold storage of milk at 4°C, 29 bacterial morpho-physiotypes were selected among 177 isolates and were identified by partial 16S rRNA gene sequencing. The results of the phylogenetic analysis showed five clusters regrouping six genera namely Stenotrophomonas, Acinetobacter, Chryseobacterium, Lactobacillus, Aeromonas and Enterococcus. Enterococcus constituted the largest cluster composed of 9 taxa with E. faecalis being the predominant species and it was the most subclustered group. The comparative genomic analysis based on 16S rRNA gene sequence of E. faecalis isolates, with related strains from different geographies and climates was performed. The observations of the genetic variation showed that seven E. faecalis strains (MH569850, MH569851, MH569854, MH569856, MH569857, MH569859 and MH569860) registered similarities of sequences less than 97%, which lead to the hypothesis that the isolates could represent a novel species of the genus Enterococcus. The minor richness of the milk microbiota analyzed in this arid region may account for the intervention of environmental factors influencing the selection and the evolution of the microflora.

OBJECTIVE To evaluate and compare the susceptibilities of bacteria found in outpatient cultures to fosfomycin and other main antibiotics commonly available in clinical practice. STUDY DESIGN A retrospective cross-sectional study was conducted using 2,673 positive urine cultures collected between 2014 and 2017 at private laboratories located in the cities of Niteroi and Sao Goncalo. Susceptibilities to fosfomycin and other antibiotics were tested using the McNemar test with the level of significance set at 5 %. RESULTS Out of the 2,673 samples tested, 94.1 % were susceptible to fosfomycin. Escherichia coli was responsible for 68.8 % of the positive samples, and susceptibility to fosfomycin was observed in 97.9 % of these cases. Susceptibility to fosfomycin in Klebsiella spp. represented 86.6 % of cases, Enterococcus spp., 94.9 % and Proteus mirabilis, 83.3 %. The highest rate of susceptibility for E. coli was observed with fosfomycin, with the only exception being imipenem (p < 0.001). Klebsiella spp. showed a similar profile, except that there was no difference between susceptibilities to fosfomycin and gentamicin (p = 0.91). Susceptibility of Enterococcus spp. to fosfomycin was like that of nitrofurantoin and ampicillin. Finally, the susceptibility of P. mirabilis to fosfomycin was greater than it was for trimethoprim-sulfamethoxazole and nitrofurantoin. CONCLUSIONS The microbiological profile established here shows substantial sensitivity to fosfomycin in the urine samples analysed. In most cases, there was a sensitivity profile that was favourable to the use of fosfomycin or at least comparable to the other antibiotics studied.

Purpose To estimate the association of cefuroxime and moxifloxacin in relation to the occurrence of endophthalmitis following phacoemulsification cataract surgery. Design Retrospective clinical cohort study. Methods We studied patients with noncomplex phacoemulsification cataract surgery in Kaiser Permanente Northern California during 2014-2019. Data were obtained for acute, postoperative endophthalmitis within 90 days of phacoemulsification, including culture and antibiogram results, intracameral and topical antibiotic agent, and dose. In a post hoc analysis, we also examined preoperative anterior chamber depth (ACD) and postoperative anterior chamber volume (ACV). Results Of 216,141 surgeries, endophthalmitis occurred in 0.020% of moxifloxacin-injected eyes and 0.013% of cefuroxime eyes (relative risk 1.62 with 95% CI 0.82-3.20, P = .16). Of the 34 (0.016%) cases of endophthalmitis, cefuroxime 1 mg was injected into 13 eyes and moxifloxacin 0.1% into 21 eyes. Organisms with antibiograms were identified in 12 (35%) cases. Of these, bacteria recovered from cefuroxime-injected eyes were resistant to cefuroxime in all cases (4/4), with Enterococcus comprising half of these. In eyes injected with moxifloxacin 0.1%, 6 out of 7 organisms were sensitive to moxifloxacin injected with 0.1 mL and in 1 eye injected with 1 mL. Streptococcus was the most common organism recovered (6/9) in moxifloxacin-injected eyes. Preoperative ACD and postoperative calculated ACV were higher in eyes injected with moxifloxacin. Conclusions Endophthalmitis cases with positive cultures were generally related to organism resistance in cefuroxime eyes but to sensitive organisms in moxifloxacin eyes. Moxifloxacin doses may have been insufficient in eyes with larger ACV.

This study aimed to determine the in vivo effectiveness of the ethanolic extract of Piper betle L. leaves against Staphylococcus aureus-infected wounds in mice and its antimicrobial properties on clinical isolates of multiple drug-resistant bacterial pathogens. Twenty mice were divided into four groups. Wounds were created in all mice under anesthesia by excision from the dorsal skin down to the subcutaneous fat and inoculating with S. aureus. After 24 h, the wound of each mouse was treated once daily by application of the respective cream. Group I was treated with mupirocin antibacterial cream; Group II received a cream base containing no active ingredient; Groups III and IV were treated with 2.5% and 5.0% concentrations of P. betle cream, respectively. Further, an in vitro study was performed by adding undiluted, 1:50 and 1:100 dilutions of the four studied creams in normal saline containing 1.5 × 108 CFU/mL of the following bacteria: antimicrobial-susceptible S. aureus, Escherichia coli, Pseudomonas aeruginosa, methicillin-resistant S. aureus, extended-spectrum β-lactamase-producing Escherichia coli, vancomycin-resistant Enterococcus, metallo-βlactamase-producing P. aeruginosa and carbapenem-resistant Klebsiella pneumoniae. The mice in Groups III and IV had significantly faster wound contraction and significantly shorter reepithelialization time than Group II (p 0.05). P. betle creams inhibited all studied bacterial strains at full concentration and at a dilution of 1:50. The inhibitory effect was more significant than Groups I and II (p 0.05) when compared with Group I. Cream formulations derived from P. betle ethanolic extract have great potential as antimicrobial agents for the treatment of wound infection. Further clinical tests are recommended to determine the safety and efficacy of these formulations in other mammalian species.

Background: Of all enterococci species, the most renowned clinically as multidrug-resistant pathogens are Enterococcus faecium and Enterococcus faecalis. Vancomycin-resistant Enterococcus (VRE) species are the principal cause of opportunistic hospital-acquired infections, due to numerous resistance mechanisms. Methods: In this study, the prevalence and antibiotic resistance profiles of VRE according to clinical sources from three selected hospitals in Southwest-Nigeria were investigated. Altogether, 431 samples (urine, rectal, and wound swabs - caesarian section (CS), automobile accidents, and other skin lesions and abrasions) were collected from three selected hospitals in Osun State, Nigeria. Established techniques were employed for the recovery of enterococci and screening for VRE while antibiotic susceptibility tests were carried out by disc diffusion technique. Results: Altogether, 208 (48.3%) enterococci strains were recovered from which 85 (40.9%) were VRE. E. faecium predominated at 71.8% (61/85) and E. faecalis at 28.2% (24/85) as determined by phenotypic characterization. VRE isolates exhibited 100%, 97.6%, and 92.9% resistance to ampicillin, clindamycin, and quinupristin-dalfopristin (Q/D) respectively. The least resistance in-vitro was to tigecycline (27.1%). None of the antibiotics exhibited 100% activity against all the isolates. vanA resistant phenotype was prevalent at 65.9%. E. faecium from all study locations displayed higher levels of resistance than E. faecalis. Multiple antibiotic resistance (MAR) indices in all VRE isolates were ≥0.2, all being multidrug-resistant. Conclusions: The high prevalence rate along with the high level of multidrug resistance observed in the present study is worrisome and poses a continuous threat in the therapy of illnesses triggered by VRE as vancomycin was perceived as a drug of choice to curb enterococcal infections.

A contaminação de fórmulas infantis pode ocorrer quando os manipuladores cometem falhas operacionais ou falhas na adequação do ambiente de preparo. O objetivo da pesquisa foi avaliar a eficácia dos procedimentos operacionais padronizados executados na área de produção de fórmulas lácteas de um Hospital. Realizou-se uma pesquisa aplicada, descritiva e explicativa com avaliação do fluxo operacional e das condições físico funcionais, análise do comportamento dos manipuladores e pesquisas microbiológicas de Coliformes totais, Escherichia coli, Bactérias aeróbias mesófilas, Bacillus cereus, Yersinia enterocolitica, Listeria monicytogenes, Clostridium perfrigens, Clostridium Sulfito Redutor, Staphylococcus coagulase positiva, Salmonella spp., Enterococcous spp, Enterobacter sakazakii, Pseudomonas aeruginosa e fungos em superfícies de fórmulas infantis e água. Os procedimentos operacionais padronizados são executados em todas as etapas do processo, entretanto, foram observadas falhas humanas. Na avaliação físico-uncional, 92% estavam em conformidade; na pesquisa microbiológica de superfícies, 12% de resultados deram presenças para Enterococcus spp., Coliformes totais, Escherichia coli e Bactérias heterotróficas aeróbias mesófilas. Nas fórmulas infantis, 8,33% dos resultados mostraram presença para Coliformes totais, Bactérias heterotróficas aeróbias mesófilas e Fungos. Os procedimentos implantados asseguram a qualidade sanitária das fórmulas, mas se verificou a necessidade de treinamento dos manipuladores. Palavras-chave: Doenças Transmitidas por Alimentos. Fórmulas Infantis. Segurança Alimentar e Nutricional. Risco Sanitário. Abstract Infant formulas contamination may occur when handlers commit operational failures or failures in the environment adequacy. The objective of this research was evaluate the effectiveness of standard operating procedures performed in the production area of milk formulations of a Hospital. An applied, descriptive and explanatory research was conducted with evaluation of operational flow and physical functional conditions, analysis of the manipulators’s behavior and microbiological investigations of MPN of total Coliforms, Escherichia col and Enterococcus spp., Count of Bacillus cereus/g, Clostridium sulfite reducer, molds and yeasts, Staphylococcus coagulase positive, aerobic mesophilic bacteria and Cronobacter sakazakii, research of Yersinia enterocolitica, Listeria monocytogenes, Salmonella spp and Pseudomonas aeruginosa on surfaces, infant formulas and water. Standard operating procedures were performed at all the process stages, however, human failures have been observed. In the physical functional evaluation, 92% was in compliance; on the surface microbiological analysis, 12% of the results present Enterococcus spp., Total Coliforms, Escherichia coli and aerobic mesophilic bacteria. In infant formulas, 8.33% results showed presence for Total Coliforms, aerobic mesophilic bacteria and Fungi. The implanted procedures assured the formulas sanitary quality, but the necessity of the manipulators’s training was verified. Keywords: Foodborne Diseases. Infant Formulas. Food and Nutrition Security. Health Risk.

In infancy most common and a serious disease is known as Urinary tract infection (UTI). The aim of the current study is to evaluate the frequency and antibiotic resistant among infant presenting with UTI in Lahore General hospital, Lahore-Pakistan. The current observational study comprised 100 (n=100) cases diagnosed with UTI. The study was conducted at Lahore General Hospital, Pakistan, between March 2019 and January 2020. Data were collected and recorded on specified proformas that had information on demographics, biochemical analysis, and complaints, as well as the antibiotic used and blood cultures. The most common gram-negative bacilli (GNB) causing UTI was E. coli constitute about 72% followed by Klebsiella (11%), Enterobacter (7%) and Enterococcus (4%). Most of the isolated pathogens are highly resistant to ampicillin, cotrimoxazole, and cephalexin (72%–95%), have intermediate sensitivity to third- generation cephalosporins, and high sensitivity to amikacin, nitrofurantoin and ciprofloxacin. Similarly, the other pathogens showed different degree of occurrence and resistance against empirically used antibiotics. The most prevalent UTI causative organism among children was E. coli. The insulated microorganisms were highly resistant to ampicillin, and highly sensitive to amikacin.

Lactic acid bacteria (LAB) are among the most prevalent microorganisms forming the autochthonous microbiota of fruit. This study aimed to select LAB isolates with probiotic aptitudes from apple, banana, grape, and orange through evaluation of in vitro safety, technological, and functional-related properties. The ability of most promising selected isolates to survive in commercial apple and orange juice, meat stew, vegetable puree, and UHT milk during 28 days of refrigeration storage was evaluated. Ninety-three isolates identified preliminarily as LAB were recovered from fruit and 66 of these isolates passed safety tests. Most of these isolates were pre-identified as belonging to Lactobacillus or Enterococcus genus based on MALDI-ToF MS profiling. These 66 isolates were categorized into three homogeneous groups based on a preliminary cluster analysis run with data from experiments to measure technological characteristics. Nine LAB isolates were selected as the most promising for probiotic use based on a principal component analysis run with data from experiments to measure probiotic-related properties. Four of these isolates were sensitive to different antibiotics and identified (16S-rRNA gene sequencing) as Lactobacillus brevis (recently reclassified as L. brevis) or Lactobacillus spp. These 4 selected isolates had high viable counts and high percentages of physiologically active cells in apple and orange juice, beef stew, vegetable puree, and UHT milk during refrigeration storage. The results showed that apple, banana, orange, and grape are potential sources of LAB with aptitudes to be exploited for a possible probiotic use and distinguished abilities to survive in different food matrices. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s42770-021-00543-x.

Bioaerosols have gained importance in atmospheric sciences in the past few decades. Their exposure upsurges the health problems in sensitive population and is also known to participate in atmospheric chemistry. The present study assesses the monthly distribution of bioaerosol load at four different microenvironments inside an academic institute in Kanpur situated in Indo-Gangetic Plain (IGP). The study duration was from November 2017 to April 2018. The measured total bioaerosol concentrations were highest during April (418–610 CFU/m3) at all sites followed by the post-monsoon month of November (369–577 CFU/m3). The winter period showed low concentrations with lowest concentration obtained in January (251–419 CFU/m3). The indoor–outdoor (I/O) bioaerosol ratio was mostly less than one for bacteria depending on microenvironment, but for fungi it was always less than one. The Gram-positive bacteria (GPB) comprised 70–80% of total bacterial concentration, while Gram-negative bacteria (GNB) contributed 20–30% to bacterial concentration in ambient air. The bacterial genera were mostly dominated by Bacillus, Staphylococcus, Micrococcus, Streptococcus, and Enterococcus, while the fungal genera of Aspergillus, Penicillium, Rhizopus, Cladosporium, Basidiobolus, and Epidermophyton were seen in the campus. The statistical analysis showed a weak positive correlation of bioaerosol concentration with meteorological parameters: temperature and relative humidity (RH).

This study aimed to isolate lactic acid bacteria (LABs) of technological interest from Moroccan camel milk and select starter or adjunct culture for dairy product manufacturing. The phenotypic and biochemical identification of 47 isolates revealed the existence of ten Lactococcus lactis, eleven Lactobacillus plantarum, three Lactobacillus brevis, two Lactobacillus paracasei, eleven Enterococcus spp., seven Lactococcus spp. and two Lactobacillus spp. Our strains showed a fast acidifying ability (ΔpH ranged between 0.69 ± 0.01 and 1.22 ± 0.05 after 6 h), high proteolytic and autolytic activities (1.93 ± 0.02 to 9.9 ± 0.022 mM glycine and 15.21 ± 2.21% to 83.24 ± 1% respectively), and an important lipolytic and free radical scavenging capacity. Furthermore, they were able to use citrate, to produce exopolysaccharide, and they exhibited antibacterial activity against Gram-negative and Gram-positive pathogenic bacteria and had no hemolytic activity. This study has shown that Moroccan camel milk represents a rich biotope of interesting LABs for dairy products industry.

Objective: This study aimed to search for Enterococcus faecalis in children's deep carious dentine and characterize their virulence traits.Material and Methods: Eight isolates from 15 carious molars identified by 16S rDNA species-specific PCR as E. faecalis were included. These eight isolates were subject to identification by MALDI-TOF and characterized regarding: (i) bacterial aggregation and biofilm formation on polystyrene and glass, with/without saliva, as single or dual-species (associated to Streptococcus mutans); (ii) environmental pH measurement before and after 24 h incubation; (iii) acidogenicity; (iv) gelatinase production; (v) macrophage adherence; and (vi) toxicity towards Caenorhabditis elegans. Statistical analyses were performed using two-way ANOVA/Tukey or Fisher's exact tests.Results: All isolates initially identified as E. faecalis by PCR were correctly identified as Lactobacillus by MALDI-TOF, being designated as Lactobacillus misidentified as Enterococcus (LME). These isolates produced biofilm in the presence of saliva and in the dual-species assays. Bacterial aggregation was only observed in the dual-species model. After 24 h, environmental pH dropped from 7.5 to 4.5 for seven of eight isolates, and to 4.0 in all dual-species models. LME isolates were acidogenic, none of them produced gelatinase or adhered to macrophages, but all presented toxicity towards C. elegans.Conclusions: No E. faecalis were identified in the children's caries lesions. All LME isolates presented important virulence traits, including biofilm formation and high acidogenicity, which cause enamel demineralization, that might increase the risk of dental caries in children carrying LME. Thus, the correct identification and in-depth virulence characterization of microorganisms isolated from dental caries are important to understand the dynamics of this disease.

Background:We analyzed 2017 healthcare facility-onset (HO) vancomycin-resistant Enterococcus (VRE) bacteremia data to identify hospital-level factors that were significant predictors of HO-VRE using the Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN) multidrug-resistant organism and Clostridioides difficile reporting module. A risk-adjusted model that can be used to calculate the number of predicted HO-VRE bacteremia events in a facility was developed, thus enabling the calculation of VRE standardized infection ratios (SIRs).Methods:Acute-care hospitals reporting at least 1 month of 2017 VRE bacteremia data were included in the analysis. Various hospital-level characteristics were assessed to develop a best-fit model and subsequently derive the 2018 national and state SIRs.Results:In 2017, 470 facilities in 35 states participated in VRE bacteremia surveillance. Inpatient VRE community-onset prevalence rate, average length of patient stay, outpatient VRE community-onset prevalence rate, and presence of an oncology unit were all significantly associated (all 95% likelihood ratio confidence limits excluded the nominal value of zero) with HO-VRE bacteremia. The 2018 national SIR was 1.01 (95% CI, 0.93–1.09) with 577 HO bacteremia events reported.Conclusion:The creation of an SIR enables national-, state-, and facility-level monitoring of VRE bacteremia while controlling for individual hospital-level factors. Hospitals can compare their VRE burden to a national benchmark to help them determine the effectiveness of infection prevention efforts over time.

*Önal Darılmaz, Zehra ( Aksaray, Yazar ), In the present study, eight strains of Enterococcus spp. were isolated from Turkish and Iranian white cheese test pieces. Enterococcus spp. strains were identified as Enterococcus faecium (6 strains) and E. faecalis (2) with 16S rDNA sequence analysis. All Enterococcus spp. strains showed susceptibility to the most of antibiotics tested in this investigation. The amount of produced acid (0.59–1.17%), hydrogen peroxide (0.65–3.91 µg/ml), and exopolysaccharide (252–362 mg/L) of these strains were determined. These strains possess the ability to inhibit Escherichia coli ATCC 35,218, Salmonella enteritidis ATCC 13,076, and Salmonella typhimurium MU 80. E. faecium RI53 and RI 42 strains were determined as the most resistant to acid (1.86 and 1.56 OD, respectively) and also exhibited high percentage of aggregation (54.1 and 51.7%, respectively). E. faecium RI 42 exhibited a higher growth viability in gastric and intestinal juice. E. faecium RI 53 and RI 42 are determined as optimal potential probiotic candidates for utilization in cheese preparations.