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TheScientificWorldJournal 2021Recently, the interest in donkey milk has increased considerably because it proved high nutritive and functional values of their ingredients. Its chemical composition is...
Recently, the interest in donkey milk has increased considerably because it proved high nutritive and functional values of their ingredients. Its chemical composition is widely studied, but its microbiota, especially lactic acid bacteria, remains less studied. This study focuses on analyzing, isolating, and identifying lactic acid bacteria and evaluating their capacity to produce biomolecules with antibacterial activity. Among 44 strains identified, 43 are Gram-positive, and most are catalase-negative and cocci-shaped. Five strains were selected to evaluate their antibacterial activity against , and . Different induction methods allowed to amplify the antibacterial effects against these pathogenic strains.
Topics: Aerococcus; Animals; Anti-Bacterial Agents; Culture Media, Conditioned; Dairying; Enterococcus; Enterococcus faecalis; Equidae; Escherichia coli; Female; Food Microbiology; Lactation; Leuconostoc mesenteroides; Listeria monocytogenes; Microbial Sensitivity Tests; Milk; Morocco; Staphylococcus aureus
PubMed: 34421400
DOI: 10.1155/2021/6664636 -
Papillomavirus Research (Amsterdam,... Jun 2019In this study we examined potential associations of HPV infection with the cervical microbiota. Cervical samples were collected from 87 HIV-seronegative reproductive-age...
In this study we examined potential associations of HPV infection with the cervical microbiota. Cervical samples were collected from 87 HIV-seronegative reproductive-age Black South African women. Microbiota were characterized by Illumina sequencing of the V3-V4 hypervariable regions of the bacterial 16S rRNA gene. Thirty seven (42.5%) and 30 (34.5%) of the women had prevalent HPV and high-risk (HR)-HPV, respectively. Only 23 women (26.4%) had cervical microbiota dominated by a single Lactobacillus species (L. crispatus (2/87 (2.3%)), L. jensenii (2/87 (2.3%)), and L. iners (19/87 (21.8%)). The majority of the women (56/87 (64.4%)) had diverse cervical microbiota consisting of mainly bacterial vaginosis-associated bacteria. The remaining women (8/87 (9.2%)) had microbiota dominated by Aerococcus, Streptococcus, Chlamydia or Corynebacterium. Women with HR-HPV had significantly higher relative abundances of Aerococcaceae, Pseudomonadaceae and Bifidobacteriaceae compared to those with low-risk (LR)-HPV or no HPV-infection (LDA score >2.0, p < 0.05, q < 0.2). Gardnerella, Sneathia, and Atopobium were also found at greater relative abundances in HR-HPV-infected women compared to those with low-risk (LR)-HPV or no HPV-infection (LDA score >2.0, p < 0.05), although the difference was not significant after FDR-adjustment (q > 0.2). Further investigations of the bacterial taxa significantly enriched in HR-HPV-infected women are warranted.
Topics: Adolescent; Adult; Bacteria; Black People; Cervix Uteri; Cluster Analysis; Cross-Sectional Studies; DNA, Bacterial; DNA, Ribosomal; Female; Humans; Longitudinal Studies; Microbiota; Middle Aged; Papillomavirus Infections; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; South Africa; Young Adult
PubMed: 30986570
DOI: 10.1016/j.pvr.2019.04.006 -
The Journal of Applied Laboratory... Jan 2020
Topics: Abiotrophia; Cerebrospinal Fluid Leak; Child; Craniotomy; Diagnosis, Differential; Electrophoresis; Humans; Infections; Neuraminidase; Postoperative Complications; Transferrin
PubMed: 31811077
DOI: 10.1373/jalm.2019.031096 -
Journal of Clinical Microbiology Sep 2021
Topics: Abiotrophia; Discitis; Endocarditis; Endocarditis, Bacterial; Gram-Positive Bacterial Infections; Humans
PubMed: 34542326
DOI: 10.1128/JCM.03093-20 -
BMJ Case Reports Jul 2016We present the case of an elderly male who was initially seen in our hospital for a urinary tract infection that was treated with oral ciprofloxacin. He was admitted...
We present the case of an elderly male who was initially seen in our hospital for a urinary tract infection that was treated with oral ciprofloxacin. He was admitted 2 weeks later with altered mental status and fever, and was found to have bacteraemia with Aerococcus urinae Owing to altered mental status a brain MRI was performed which showed evidence of embolic stroke. Following this, a transesophageal echocardiogram showed severe mitral regurgitation and a vegetation >1 cm involving the mitral valve with associated destruction of posterior valve leaflets. The patient was started on antibiotics intravenous penicillin G and intravenous gentamicin for a total duration of 6 weeks. He underwent mitral valve replacement on day 4 of hospitalisation. The postoperative course was complicated by ventilator-dependent respiratory failure, requiring tracheostomy and eventual transfer to a skilled nursing facility. Unfortunately, he died after 2 weeks of stay at the facility.
Topics: Aerococcus; Aged; Anti-Bacterial Agents; Brain; Echocardiography, Transesophageal; Endocarditis, Bacterial; Fatal Outcome; Gentamicins; Humans; Magnetic Resonance Imaging; Male; Mitral Valve; Mitral Valve Insufficiency; Penicillins; Stroke; Urinary Tract Infections
PubMed: 27440847
DOI: 10.1136/bcr-2016-215421 -
PloS One 2016The bacterial communities present in smokeless tobacco (ST) products have not previously reported. In this study, we used Next Generation Sequencing to study the...
The bacterial communities present in smokeless tobacco (ST) products have not previously reported. In this study, we used Next Generation Sequencing to study the bacteria present in U.S.-made dry snuff, moist snuff and Sudanese toombak. Sample diversity and taxonomic abundances were investigated in these products. A total of 33 bacterial families from four phyla, Actinobacteria, Firmicutes, Proteobacteria and Bacteroidetes, were identified. U.S.-produced dry snuff products contained a diverse distribution of all four phyla. Moist snuff products were dominated by Firmicutes. Toombak samples contained mainly Actinobacteria and Firmicutes (Aerococcaceae, Enterococcaceae, and Staphylococcaceae). The program PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) was used to impute the prevalence of genes encoding selected bacterial toxins, antibiotic resistance genes and other pro-inflammatory molecules. PICRUSt also predicted the presence of specific nitrate reductase genes, whose products can contribute to the formation of carcinogenic nitrosamines. Characterization of microbial community abundances and their associated genomes gives us an indication of the presence or absence of pathways of interest and can be used as a foundation for further investigation into the unique microbiological and chemical environments of smokeless tobacco products.
Topics: Bacteria; Bacterial Toxins; DNA, Bacterial; DNA, Ribosomal; Drug Resistance, Bacterial; High-Throughput Nucleotide Sequencing; Metagenome; Phylogeny; RNA, Ribosomal, 16S; Software; Tobacco, Smokeless; United States
PubMed: 26784944
DOI: 10.1371/journal.pone.0146939 -
Infection and Immunity Oct 2010The Gram-positive bacterium Aerococcus urinae can cause infectious endocarditis (IE) in older persons. Biofilm formation and platelet aggregation are believed to...
The Gram-positive bacterium Aerococcus urinae can cause infectious endocarditis (IE) in older persons. Biofilm formation and platelet aggregation are believed to contribute to bacterial virulence in IE. Five A. urinae isolates from human blood were shown to form biofilms in vitro, and biofilm formation was enhanced by the presence of human plasma. Four of the A. urinae isolates caused platelet aggregation in platelet-rich plasma from healthy donors. The Au3 isolate, which induced platelet aggregation in all donors, also activated platelets, as determined by flow cytometry. Platelet aggregation was dependent on bacterial protein structures and on platelet activation since it was sensitive to both trypsin and prostaglandin E(1). Plasma proteins at the bacterial surface were needed for platelet aggregation; and roles of the complement system, fibrinogen, and immunoglobulin G were demonstrated. Complement-depleted serum was unable to support platelet aggregation by Au3 and complement blockade using compstatin-inhibited platelet activation. Platelet activation by Au3 was inhibited by blocking of the platelet fibrinogen receptor, and this isolate was also shown to bind to radiolabeled fibrinogen. Removal of IgG from platelet-rich plasma by a specific protease inhibited the platelet aggregation induced by A. urinae, and blockade of the platelet FcRγIIa hindered platelet activation induced by Au3. Convalescent-phase serum from a patient with A. urinae IE transferred the ability of the bacterium to aggregate platelets in an otherwise nonresponsive donor. Our results show that A. urinae exhibits virulence strategies of importance for IE.
Topics: Aerococcus; Biofilms; Blood Platelets; Complement System Proteins; Endocarditis, Bacterial; Fibrinogen; Humans; Immunoglobulin G; Plasma; Platelet Activation; Virulence
PubMed: 20696834
DOI: 10.1128/IAI.00469-10 -
Clinical Microbiology and Infection :... Jun 2012Aerococcus urinae is a Gram-positive bacterium that can cause invasive infection, including infectious endocarditis (IE), mainly in older men. A. urinae is often...
Aerococcus urinae is a Gram-positive bacterium that can cause invasive infection, including infectious endocarditis (IE), mainly in older men. A. urinae is often misclassified in routine diagnostic laboratories. Through searches in the laboratory databases we identify 16 isolates of A. urinae causing bacteraemia during a 6-year period in southern Sweden, indicating that bacteraemia with A. urinae occurs in at least three cases per million inhabitants per year. The identity of isolates was confirmed by sequencing of the 16S rRNA genes and antibiotic susceptibility testing identified two ciprofloxacin-resistant isolates. A. urinae was the only significant pathogen isolated in all cases. Fifteen of the 16 patients were male, 15/16 were more than 70 years old, and 12/16 had underlying urological conditions. Though a urinary tract focus was suspected in the majority of cases, the bacterium was rarely found in urinary samples. Nine patients fulfilled the criteria for severe sepsis and an additional four fulfilled the criteria for sepsis. Only one fatality was recorded. Patients were treated mainly with beta-lactam antibiotics but fluoroquinolones and clindamycin were also used. Three cases of IE were diagnosed and these were complicated by spondylodiscitis in one case and by septic embolization to the brain in one case. An increased awareness of A. urinae is crucial to establishing its role as an important pathogen in older men with urinary tract disease.
Topics: Aerococcus; Aged; Anti-Bacterial Agents; Bacteremia; Drug Resistance, Bacterial; Gram-Positive Bacterial Infections; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Prevalence; Sex Factors; Survival Analysis; Sweden; Urinary Tract Infections
PubMed: 21895858
DOI: 10.1111/j.1469-0691.2011.03609.x -
Anales Del Sistema Sanitario de Navarra Dec 2020Abiotrophia defectiva is a rare cause of endocarditis with a high embolization rate compared to other streptococcal endocarditis. Neurological complications may occur in...
Abiotrophia defectiva is a rare cause of endocarditis with a high embolization rate compared to other streptococcal endocarditis. Neurological complications may occur in 20-40% of cases, and include intracranial aneurysms and sub-arachnoid hemorrhage. Its isolation in the central nervous system (CNS) is extremely rare and is associated with previous neurosurgical procedures. We present the case of a 51-year-old patient who suffered an ischemic stroke as a complication of A. defectiva endocarditis, and the cases of CNS infections caused by this microorganism are reviewed. The relevance of the case lies in its singular character, due to the absence of previous valve disease in the patient without a recent history of invasive procedures or surgical interventions.
Topics: Abiotrophia; Embolic Stroke; Endocarditis, Bacterial; Gram-Positive Bacterial Infections; Humans; Middle Aged
PubMed: 32814921
DOI: 10.23938/ASSN.0881 -
PloS One 2015Probiotics are increasingly used in aquaculture to control diseases and improve feed digestion and pond water quality; however, little is known about the antimicrobial... (Comparative Study)
Comparative Study
Probiotics are increasingly used in aquaculture to control diseases and improve feed digestion and pond water quality; however, little is known about the antimicrobial resistance properties of such probiotic bacteria and to what extent they may contribute to the development of bacterial resistance in aquaculture ponds. Concerns have been raised that the declared information on probiotic product labels are incorrect and information on bacterial composition are often missing. We therefore evaluated seven probiotics commonly used in Vietnamese shrimp culture for their bacterial species content, phenotypic antimicrobial resistance and associated transferable resistance genes. The bacterial species was established by 16S rRNA sequence analysis of 125 representative bacterial isolates. MIC testing was done for a range of antimicrobials and whole genome sequencing of six multiple antimicrobial resistant Bacillus spp. used to identify resistance genes and genetic elements associated with horizontal gene transfer. Thirteen bacterial species declared on the probiotic products could not be identified and 11 non-declared Bacillus spp. were identified. Although our culture-based isolation and identification may have missed a few bacterial species present in the tested products this would represent minor bias, but future studies may apply culture independent identification methods like pyro sequencing. Only 6/60 isolates were resistant to more than four antimicrobials and whole genome sequencing showed that they contained macrolide (ermD), tetracycline (tetL), phenicol (fexA) and trimethoprim (dfrD, dfrG and dfrK) resistance genes, but not known structures associated with horizontal gene transfer. Probiotic bacterial strains used in Vietnamese shrimp culture seem to contribute with very limited types and numbers of resistance genes compared to the naturally occurring bacterial species in aquaculture environments. Approval procedures of probiotic products must be strengthened through scientific-based efficacy trials and product labels should allow identification of individual bacterial strains and inform the farmer on specific purpose, dosage and correct application measures.
Topics: Aerococcus; Animals; Aquaculture; Bacillus; Bacteria; DNA, Bacterial; DNA, Ribosomal; Drug Resistance, Bacterial; Drug Resistance, Multiple, Bacterial; Genes, Bacterial; Klebsiella; Penaeidae; Phylogeny; Probiotics; R Factors; RNA, Bacterial; RNA, Ribosomal, 16S; Ribotyping; Sequence Alignment; Sequence Homology, Nucleic Acid; Vietnam
PubMed: 26147573
DOI: 10.1371/journal.pone.0132338