Search results for "Bacterial"
showing 10 items of 3246 documents
Spectrophotometric analysis of crown discoloration following the use of silver nanoparticles combined with calcium hydroxide as intracanal medicament
2017
Background Optimal antibacterial efficacy of intracanal medicaments containing silver nanoparticles (Ag-NPs) has been well documented. However, concerns remain regarding the effect of Ag-NPs on tooth color. This study aimed to assess the effects of calcium hydroxide (CH) mixed with Ag-NPs as intracanal medicaments on tooth color. The effect of location of application of medicament on the degree of discoloration was evaluated as well. Material and Methods Fifty extracted single-rooted, single-canal human teeth with straight roots, no caries, no cracks or fractures were collected and accessed. After cleaning and shaping of the root canals, the teeth were randomly divided into two experimental…
Interaction of Intestinal Bacteria with Human Rotavirus during Infection in Children
2021
The gut microbiota has emerged as a key factor in the pathogenesis of intestinal viruses, including enteroviruses, noroviruses and rotaviruses (RVs), where stimulatory and inhibitory effects on infectivity have been reported. With the aim of determining whether members of the microbiota interact with RVs during infection, a combination of anti-RV antibody labeling, fluorescence-activated cell sorting and 16S rRNA amplicon sequencing was used to characterize the interaction between specific bacteria and RV in stool samples of children suffering from diarrhea produced by G1P[8] RV. The genera Ruminococcus and Oxalobacter were identified as RV binders in stools, displaying enrichments between …
Modulation of Saliva Microbiota through Prebiotic Intervention in HIV-Infected Individuals
2019
Human immunodeficiency virus (HIV) infection is characterized by an early depletion of the mucosal associated T helper (CD4+) cells that impair the host immunity and impact the oral and gut microbiomes. Although, the HIV-associated gut microbiota was studied in depth, few works addressed the dysbiosis of oral microbiota in HIV infection and, to our knowledge, no studies on intervention with prebiotics were performed. We studied the effect of a six-week-long prebiotic administration on the salivary microbiota in HIV patients and healthy subjects. Also, the co-occurrence of saliva microorganisms in the fecal bacteria community was explored. We assessed salivary and feces microbiota compositio…
mcr-1- like detection in commensal Escherichia coli and Salmonella spp. from food-producing animals at slaughter in Europe
2017
International audience; We evaluate here the presence of the mcr-1-like and mcr-2 genes in Escherichia coli and Salmonella spp. isolated from healthy food-producing animals at slaughter between 2002 and 2014 in Europe. Isolates were retrieved from cattle, pig and chicken from 11 European countries of production. The susceptibility to colistin and antibiotics used in human medicine was determined by agar dilution. Colistin-resistant isolates were PCR-screened for mcr genes. mcr-positive isolates were typed by Pulsed-Field Gel Electrophoresis (PFGE) and Multi-Locus Sequence Typing. Among the 10,206 E. coli and 1774 Salmonella spp. isolated from cattle, pigs and chickens, 148 E. coli and 92 Sa…
The SCO1731 methyltransferase modulates actinorhodin production and morphological differentiation of Streptomyces coelicolor A3(2)
2018
AbstractStreptomyces coelicolor is a Gram-positive microorganism often used as a model of physiological and morphological differentiation in streptomycetes, prolific producers of secondary metabolites with important biological activities. In the present study, we analysed Streptomyces coelicolor growth and differentiation in the presence of the hypo-methylating agent 5′-aza-2′-deoxycytidine (5-aza-dC) in order to investigate whether cytosine methylation has a role in differentiation. We found that cytosine demethylation caused a delay in spore germination, aerial mycelium development, sporulation, as well as a massive impairment of actinorhodin production. Thus, we searched for putative DNA…
Cocirculation of Hajj and non-Hajj strains among serogroup W meningococci in Italy, 2000 to 2016
2019
In Italy, B and C are the predominant serogroups among meningococci causing invasive diseases. Nevertheless, in the period from 2013 to 2016, an increase in serogroup W Neisseria meningitidis (MenW) was observed. This study intends to define the main characteristics of 63 MenW isolates responsible of invasive meningococcal disease (IMD) in Italy from 2000 to 2016. We performed whole genome sequencing on bacterial isolates or single gene sequencing on culture-negative samples to evaluate molecular heterogeneity. Our main finding was the cocirculation of the Hajj and the South American sublineages belonging to MenW/clonal complex (cc)11, which gradually surpassed the MenW/cc22 in Italy. All M…
No diagnostic utility of antibody patterns against Klebsiella pneumoniae capsular serotypes in patients with axial spondyloarthritis vs. patients wit…
2017
OBJECTIVES: To investigate whether antibody response patterns against Klebsiella pneumoniae capsular serotypes can discriminate patients with axial spondyloarthritis (axSpA) from patients with non-specific low back pain (LBP).METHOD: Immunoglobulin (Ig)G and IgA antibodies against K. pneumoniae capsular serotypes K2, K26, K36, and K50 were measured, and antibody seropositivity compared between groups and analysed for patient correlation in five different groups: (a) 96 patients fulfilling the Assessment of SpondyloArthritis International Society (ASAS) classification criteria for axSpA; (b) 38 patients with either a positive magnetic resonance imaging (MRI) scan as defined by ASAS or a posi…
Reinventing the Wheel and Making It Round Again: Evolutionary Convergence in Buchnera-Serratia Symbiotic Consortia between the Distantly Related Lach…
2016
International audience; Virtually all aphids (Aphididae) harbor Buchnera aphidicola as an obligate endosymbiont to compensate nutritional deficiencies arising from their phloem diet. Many species within the Lachninae subfamily seem to be consistently associated also with Serratia symbiotica We have previously shown that both Cinara (Cinara) cedri and Cinara (Cupressobium) tujafilina (Lachninae: Eulachnini tribe) have indeed established co-obligate associations with both Buchnera and S. symbiotica However, while Buchnera genomes of both Cinara species are similar, genome degradation differs greatly between the two S. symbiotica strains. To gain insight into the essentiality and degree of int…
Snapshots of a shrinking partner: Genome reduction inSerratia symbiotica
2016
AbstractGenome reduction is pervasive among maternally-inherited endosymbiotic organisms, from bacteriocyte- to gut-associated ones. This genome erosion is a step-wise process in which once free-living organisms evolve to become obligate associates, thereby losing non-essential or redundant genes/functions. Serratia symbiotica (Gammaproteobacteria), a secondary endosymbiont present in many aphids (Hemiptera: Aphididae), displays various characteristics that make it a good model organism for studying genome reduction. While some strains are of facultative nature, others have established co-obligate associations with their respective aphid host and its primary endosymbiont (Buchnera). Further…
Formation and Characterization of Early Bacterial Biofilms on Different Wood Typologies Applied in Dairy Production
2018
ABSTRACT The main hypothesis of this work was that Sicilian forestry resources are suitable for the production of equipment to be used in cheese making and indigenous milk lactic acid bacteria (LAB) are able to develop stable biofilms providing starter and nonstarter cultures necessary for curd fermentation and cheese ripening, respectively. Hence, the present work was carried out with deproteinized whey to evaluate LAB biofilm formation on different woods derived from tree species grown in Sicily. Microbiological and scanning electron microscopy analyses showed minimal differences in microbial levels and compositions for the neoformed biofilms. The specific investigation of Salmonella spp.…