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1.
World J Microbiol Biotechnol ; 39(12): 357, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37882859

RESUMEN

Dental biofilms represent a serious oral health problem playing a key role in the development of caries and other oral diseases. In the present work, we cloned and expressed in E. coli two glucanases, Prevotella melaninogenica mutanase (PmGH87) and Capnocytophaga ochracea dextranase (CoGH66), and characterized them biochemically and biophysically. Their three-dimensional structures were elucidated and discussed. Furthermore, we tested the capacity of the enzymes to hydrolyze mutan and dextran to prevent formation of Streptococcus mutans biofilms, as well as to degrade pre- formed biofilms in low and abundant sugar conditions. The percentage of residual biofilm was calculated for each treatment group in relation to the control, as well as the degree of synergism. Our results suggest that both PmGH87 and CoGH66 are capable of inhibiting biofilm formation grown under limited or abundant sucrose conditions. Degradation of pre-formed biofilms experiments reveal a time-dependent effect for the treatment with each enzyme alone. In addition, a synergistic and dose-dependent effects of the combined enzymatic treatment with the enzymes were observed. For instance, the highest biomass degradation was 95.5% after 30 min treatment for the biofilm grown in low sucrose concentration, and 93.8% after 2 h treatment for the biofilm grown in sugar abundant condition. Strong synergistic effects were observed, with calculated degree of synergism of 5.54 and 3.18, respectively and their structural basis was discussed. Jointly, these data can pave the ground for the development of biomedical applications of the enzymes for controlling growth and promoting degradation of established oral biofilms.


Asunto(s)
Escherichia coli , Prevotella melaninogenica , Escherichia coli/genética , Biopelículas , Sacarosa
2.
Clin Exp Immunol ; 209(2): 215-224, 2022 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-35605143

RESUMEN

Oral lichen planus (OLP) is a common chronic inflammatory disease occurring in the oral mucosa. Bacteria are a key driver of mucosal immune responses and can induce changes in gene expression and function of epithelial keratinocytes. IL-36γ can induce the expression of antimicrobial peptides, cytokines, and chemokines, and is widely involved in many chronic inflammatory diseases. Our aim is to explore the role of IL-36γ in the pathological process of OLP when Prevotella melaninogenica (P. melaninogenica) invades the oral mucosa. The expression of IL-36γ in OLP lesions and mice was detected by immunohistochemistry. Recombinant human IL-36Gamma (rhIL-36γ) was used to treat oral keratinocytes and the expression levels of inflammatory cytokines were detected by qRT-PCR and ELISA. The expression of IL-36γ and TRPV1 was detected by western blotting following co-culturing P. melaninogenica with oral keratinocytes. The mRNA expression of IL-36γ was detected by qRT-PCR. From our results, IL-36γ was upregulated in OLP lesions. Exogenous rhIL-36γ promoted the expression of pro-inflammatory cytokines and antibacterial peptides in oral keratinocytes. The expression of IL-36γ was significantly increased following the stimulation of P. melaninogenica in oral keratinocytes and mice. TRPV1 activation was induced by P. melaninogenica and its activation enhanced the expression of IL-36γ. IL-36Ra could reduce the inflammation in OLP in vitro. In summary, overexpression of IL-36γ in OLP lesions could promote its pathogenesis by inducing inflammation. P. melaninogenica invasion of oral keratinocytes could induce the expression of IL-36γ by the activation of TRPV1, thereby regulating the interaction between bacteria and oral epithelial cells.


Asunto(s)
Liquen Plano Oral , Animales , Citocinas/metabolismo , Humanos , Inflamación/patología , Queratinocitos/metabolismo , Ratones , Prevotella melaninogenica/metabolismo
3.
Oral Dis ; 28(6): 1580-1590, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33780104

RESUMEN

OBJECTIVE: Oral lichen planus (OLP) is a chronic inflammatory disease that occurs in the oral mucosa with characteristic white striations lesions, recurrent erosions, and pains. The etiology and pathogenesis of OLP are still unclear. MATERIALS AND METHODS: We analyzed the bacterial community structure of buccal mucosa in patients with OLP and normal controls by high-throughput sequencing. Fluorescence in situ hybridization (FISH) was used to detect Prevotella melaninogenica (P. melaninogenica) in 13 OLP samples and 10 controls. The amounts of P. melaninogenica in OLP buccal mucosa and the expression of inflammatory cytokines in co-culture of mouse-derived macrophages with P. melaninogenica were detected by RT-qPCR. RESULTS: The P. melaninogenica was more abundant in OLP than in healthy controls, and the differences were significant at the level of the phylum, family, genus, and species (p < .05). FISH showed that P. melaninogenica can invade the epithelium and even the lamina propria of OLP, while no invasion was found in the normal mucosa. Prevotella melaninogenica can adhere to and invade macrophages and then activate the transcription of IL-1ß, IL-6, and TNF-α in NF-κB signaling pathway. CONCLUSION: Prevotella melaninogenica may be involved in the pathogenic process of OLP, and its specific mechanism deserves further study.


Asunto(s)
Liquen Plano Oral , Animales , Citocinas/metabolismo , Hibridación Fluorescente in Situ , Liquen Plano Oral/patología , Ratones , Mucosa Bucal/patología , Prevotella melaninogenica/genética , Prevotella melaninogenica/metabolismo
4.
Am J Respir Crit Care Med ; 203(9): 1099-1111, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33166473

RESUMEN

Rationale: Cross-sectional human data suggest that enrichment of oral anaerobic bacteria in the lung is associated with an increased T-helper cell type 17 (Th17) inflammatory phenotype.Objectives: In this study, we evaluated the microbial and host immune-response dynamics after aspiration with oral commensals using a preclinical mouse model.Methods: Aspiration with a mixture of human oral commensals (MOC; Prevotella melaninogenica, Veillonella parvula, and Streptococcus mitis) was modeled in mice followed by variable time of killing. The genetic backgrounds of mice included wild-type, MyD88-knockout, and STAT3C backgrounds.Measurements and Main Results: 16S-rRNA gene sequencing characterized changes in microbiota. Flow cytometry, cytokine measurement via Luminex and RNA host-transcriptome sequencing was used to characterize the host immune phenotype. Although MOC aspiration correlated with lower-airway dysbiosis that resolved within 5 days, it induced an extended inflammatory response associated with IL-17-producing T cells lasting at least 14 days. MyD88 expression was required for the IL-17 response to MOC aspiration, but not for T-cell activation or IFN-γ expression. MOC aspiration before a respiratory challenge with S. pneumoniae led to a decrease in hosts' susceptibility to this pathogen.Conclusions: Thus, in otherwise healthy mice, a single aspiration event with oral commensals is rapidly cleared from the lower airways but induces a prolonged Th17 response that secondarily decreases susceptibility to S. pneumoniae. Translationally, these data implicate an immunoprotective role of episodic microaspiration of oral microbes in the regulation of the lung immune phenotype and mitigation of host susceptibility to infection with lower-airway pathogens.


Asunto(s)
Infecciones Neumocócicas/prevención & control , Streptococcus pneumoniae , Células Th17/fisiología , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Factor 88 de Diferenciación Mieloide/fisiología , Infecciones Neumocócicas/etiología , Prevotella melaninogenica , Streptococcus mitis , Veillonella
5.
Anaerobe ; 68: 102237, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32721554

RESUMEN

The human intestinal tract is colonized by a large number of diverse microorganisms that play various important physiologic functions. In inflammatory gut diseases including celiac disease (CeD), a dysbiotic state of microbiome has been observed. Interestingly, this perturbed microbiome is normalized towards eubiosis in patients showing recovery after treatment. The treatment has been observed to increase the abundance of beneficial microbes in comparison to non-treated patients. In this study, we investigated the effect of Prevotella histicola or Prevotella melaninogenica, isolated from the duodenum of a treated CeD patient, on the induction and maintenance of oral tolerance to gliadin, a CeD associated subgroup of gluten proteins, in NOD.DQ8.ABo transgenic mice. Conventionally raised mice on a gluten free diet were orally gavaged with bacteria before and after injection with pepsin trypsin digested gliadin (PTD-gliadin). P. histicola suppressed the cellular response to gliadin, whereas P. melaninogenica failed to suppress an immune response against gliadin. Interestingly, tolerance to gliadin in NOD.DQ8.ABo mice may be associated with gut microbiota as mice gavaged with P melaninogenica harbored a different microbial diversity as compared to P. histicola treated mice. This study provides experimental evidence that gut microbes like P. histicola from treated patients can suppress the immune response against gliadin epitopes.


Asunto(s)
Enfermedad Celíaca/inmunología , Enfermedad Celíaca/microbiología , Microbioma Gastrointestinal , Gliadina/inmunología , Linfocitos T/inmunología , Animales , Femenino , Humanos , Tolerancia Inmunológica , Masculino , Ratones , Ratones Endogámicos NOD , Prevotella/inmunología , Prevotella/fisiología , Prevotella melaninogenica/inmunología , Prevotella melaninogenica/fisiología
6.
Arch Biochem Biophys ; 682: 108278, 2020 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-31981541

RESUMEN

Oral microbes are a contributing factor to hyperglycemia by inducing an increase in insulin resistance resulting in uncontrolled blood glucose levels. However, the relationship between the distribution of oral flora and hyperglycemia is still controversial. Combining the power of MALDI-Biotyper with anaerobic bacterial culture, this study explores the correlation between anaerobic bacteria in the oral cavity and blood glucose levels. The results demonstrated that altered blood glucose levels contributed to a varied bacterial distribution in the oral cavity. Specifically, Veillonella spp. and Prevotella spp. were identified in a higher proportion in people with elevated blood glucose levels. Six bacterial species identified in this study (Prevotella melaninogenica, Campylobacter rectus, Streptococcus gordonii, Streptococcus mitis, Streptococcus salivarius, and Veillonella parvula) not only demonstrated a positive association with higher blood glucose levels, but also likely contribute to the development of the condition. The data demonstrated MALDI-TOF MS to be a simpler, faster, and more economical clinical identification tool that provides clarity and depth to the research on blood glucose and oral microbiota.


Asunto(s)
Encía/microbiología , Hiperglucemia/microbiología , Microbiota , Saliva/microbiología , Adulto , Anciano , Bacterias Anaerobias , Glucemia/análisis , Campylobacter rectus , Femenino , Hemoglobina Glucada/análisis , Humanos , Masculino , Persona de Mediana Edad , Prevotella/metabolismo , Prevotella melaninogenica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Streptococcus gordonii , Streptococcus mitis , Streptococcus salivarius , Veillonella/metabolismo
7.
Nitric Oxide ; 83: 1-10, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30528912

RESUMEN

There is conflicting evidence on whether dietary nitrate supplementation can improve exercise performance. This may arise from the complex nature of nitric oxide (NO) metabolism which causes substantial inter-individual variability, within-person biological variation (CVB), and analytical imprecision (CVA) in experimental endpoints. However, no study has quantified the CVA and CVB of NO metabolites or the factors that influence their production. These data are important to calculate the critical difference (CD), defined as the smallest difference between sequential measurements required to signify a true change. The main aim of the study was to evaluate the CVB, CVA, and CD for markers of NO availability (nitrate and nitrite) in plasma and saliva before and after the ingestion of nitrate-rich beetroot juice (BR). We also assessed the CVB of nitrate-reducing bacteria from the dorsal surface of the tongue. It was hypothesised that there would be substantial CVB in markers of NO availability and the abundance of nitrate-reducing bacteria. Ten healthy male participants (age 25 ±â€¯5 years) completed three identical trials at least 6 days apart. Blood and saliva were collected before and after (2, 2.5 and 3 h) ingestion of 140 ml of BR (∼12.4 mmol nitrate) and analysed for [nitrate] and [nitrite]. The tongue was scraped and the abundance of nitrate-reducing bacterial species were analysed using 16S rRNA next generation sequencing. There was substantial CVB for baseline concentrations of plasma (nitrate 11.9%, nitrite 9.0%) and salivary (nitrate 15.3%, nitrite 32.5%) NO markers. Following BR ingestion, the CVB for nitrate (plasma 3.8%, saliva 12.0%) and salivary nitrite (24.5%) were lower than baseline, but higher for plasma nitrite (18.6%). The CD thresholds that need to be exceeded to ensure a meaningful change from baseline are 25, 19, 37, and 87% for plasma nitrate, plasma nitrite, salivary nitrate, and salivary nitrite, respectively. The CVB for selected nitrate-reducing bacteria detected were: Prevotella melaninogenica (37%), Veillonella dispar (35%), Haemophilus parainfluenzae (79%), Neisseria subflava (70%), Veillonella parvula (43%), Rothia mucilaginosa (60%), and Rothia dentocariosa (132%). There is profound CVB in the abundance of nitrate-reducing bacteria on the tongue and the concentration of NO markers in human saliva and plasma. Where these parameters are of interest following experimental intervention, the CD values presented in this study will allow researchers to interpret the meaningfulness of the magnitude of the change from baseline.


Asunto(s)
Antibacterianos/farmacología , Nitratos/farmacología , Óxido Nítrico/metabolismo , Administración Oral , Adulto , Antibacterianos/administración & dosificación , Biomarcadores/sangre , Biomarcadores/metabolismo , Jugos de Frutas y Vegetales , Haemophilus parainfluenzae/efectos de los fármacos , Voluntarios Sanos , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Micrococcaceae/efectos de los fármacos , Neisseria/efectos de los fármacos , Nitratos/administración & dosificación , Óxido Nítrico/sangre , Prevotella melaninogenica/efectos de los fármacos , Veillonella/efectos de los fármacos
8.
J Infect Chemother ; 25(5): 368-370, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30686700

RESUMEN

The significance of anaerobic bacteria as a pathogen in urinary tract infection (UTI) in children is unclear. A two-month-old infant presenting with poor feeding received a diagnosis of polymicrobial anaerobic UTI by next-generation sequencing and was found to have obstructive uropathy. Anaerobic bacteria may be a cause of UTI in children with urinary tract obstruction.


Asunto(s)
Antibacterianos/uso terapéutico , Bacterias Anaerobias/aislamiento & purificación , Prevotella melaninogenica/aislamiento & purificación , Pionefrosis/microbiología , Infecciones Urinarias/microbiología , Quimioterapia Combinada , Femenino , Humanos , Lactante , Pionefrosis/diagnóstico por imagen , Pionefrosis/terapia , Pionefrosis/orina , Resultado del Tratamiento , Ultrasonografía , Cateterismo Urinario , Infecciones Urinarias/diagnóstico por imagen , Infecciones Urinarias/terapia , Infecciones Urinarias/orina
9.
Microbiol Immunol ; 62(9): 554-566, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30028034

RESUMEN

Prevotella melaninogenica is a gram-negative anaerobic commensal bacterium that resides in the human oral cavity and is isolated as a pathogen of suppurative diseases both inside and outside the mouth. However, little is known about the pathogenic factors of P. melaninogenica. The periodontal pathogens Porphyromonas gingivalis and Tanerella forsythia secrete virulence factors such as protease and bacterial cell surface proteins via a type IX secretion system (T9SS) that are involved in pathogenicity. P. melaninogenica also possesses all known orthologs of T9SS. In this study, a P. melaninogenica GAI 07411 mutant deficient in the orthologue of the T9SS-encoding gene, porK, was constructed. Hemagglutination and biofilm formation were decreased in the porK mutant. Furthermore, following growth on skim milk-containing medium, the diameters of the halos surrounding the porK mutant were smaller than those of the wild-type strain, suggesting a decrease in secretion of proteases outside the bacterium. To investigate this in detail, culture supernatants of wild-type and porK mutant strains were purified and compared by two-dimensional electrophoresis. In the mutant strain, fewer spots were detected, indicating fewer secreted proteins. In infection experiments, the mortality rate of mice inoculated with the porK mutant strain was significantly lower than in the wild-type strain. These results suggest that P. melaninogenica secretes potent virulence factors via the T9SS that contribute to its pathogenic ability.


Asunto(s)
Proteínas Bacterianas/genética , Sistemas de Secreción Bacterianos/genética , Sistemas de Secreción Bacterianos/metabolismo , Genes Bacterianos/genética , Prevotella melaninogenica/genética , Prevotella melaninogenica/patogenicidad , Factores de Virulencia/genética , Factores de Virulencia/metabolismo , Animales , Proteínas Bacterianas/metabolismo , Infecciones por Bacteroidaceae/microbiología , Biopelículas/crecimiento & desarrollo , Femenino , Perfilación de la Expresión Génica , Sitios Genéticos , Hemaglutinación , Proteínas de Transporte de Membrana/genética , Ratones , Ratones Endogámicos BALB C , Mortalidad , Boca/microbiología , Mutación , Péptido Hidrolasas/metabolismo , Enfermedades Periodontales/microbiología , Prevotella melaninogenica/citología , Prevotella melaninogenica/crecimiento & desarrollo , Virulencia
10.
Int J Mol Sci ; 19(4)2018 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-29659523

RESUMEN

Bovine postpartum diseases remain one of the most significant and highly prevalent illnesses with negative effects on the productivity, survival, and welfare of dairy cows. Antibiotics are generally considered beneficial in the treatment of endometritis; however, frequent usage of each antibiotic drug is reason for the emergence of multidrug resistance (MDR) of the pathogenic microorganisms, representing a major impediment for the successful diagnosis and management of infectious diseases in both humans and animals. We synthesized silver nanoparticles (AgNPs) with an average size of 10 nm using the novel biomolecule apigenin as a reducing and stabilizing agent, and evaluated the efficacy of the AgNPs on the MDR pathogenic bacteria Prevotella melaninogenica and Arcanobacterium pyogenes isolated from uterine secretion samples. AgNPs inhibited cell viability and biofilm formation in a dose- and time-dependent manner. Moreover, the metabolic toxicity of the AgNPs was assessed through various cellular assays. The major toxic effect of cell death was caused by an increase in oxidative stress, as evidenced by the increased generation of reactive oxygen species (ROS), malondialdehyde, protein carbonyl content, and nitric oxide. The formation of ROS is considered to be the primary mechanism of bacterial death. Therefore, the biomolecule-mediated synthesis of AgNPs shows potential as an alternative antimicrobial therapy for bovine metritis and endometritis.


Asunto(s)
Antibacterianos/uso terapéutico , Arcanobacterium/fisiología , Endometritis/tratamiento farmacológico , Endometritis/microbiología , Nanopartículas del Metal/química , Prevotella melaninogenica/fisiología , Plata/uso terapéutico , Animales , Antibacterianos/farmacología , Antioxidantes/farmacología , Apigenina/química , Arcanobacterium/efectos de los fármacos , Biopelículas/efectos de los fármacos , Biomarcadores/metabolismo , Bovinos , Enfermedades de los Bovinos/tratamiento farmacológico , Enfermedades de los Bovinos/patología , ADN/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Oxidación-Reducción , Estrés Oxidativo/efectos de los fármacos , Prevotella melaninogenica/efectos de los fármacos , ARN/metabolismo , Plata/farmacología , Factores de Tiempo
11.
Anaerobe ; 43: 43-46, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27913316

RESUMEN

Actinotignum schaalii (formerly Actinobaculum schaalii) is a Gram-positive, facultative anaerobic rod that is typically involved in urinary tract infections in elderly patients or those with underlying urological pathologies. In contrast, abscess formation caused by A. schaalii is very rare. We present a case of multiple abscesses in the perineal area in a young patient with hidradenitis suppurativa associated with A. schaalii and Prevotella melaninogenica and review the relevant literature on the topic.


Asunto(s)
Absceso/diagnóstico , Actinomycetaceae/aislamiento & purificación , Infecciones Bacterianas/diagnóstico , Infecciones por Bacteroidaceae/complicaciones , Hidradenitis Supurativa/complicaciones , Prevotella melaninogenica/aislamiento & purificación , Absceso/complicaciones , Absceso/tratamiento farmacológico , Actinomycetaceae/clasificación , Actinomycetaceae/genética , Adulto , Infecciones Bacterianas/microbiología , Infecciones por Bacteroidaceae/microbiología , ADN Ribosómico/química , ADN Ribosómico/genética , Hidradenitis Supurativa/microbiología , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Filogenia , Prevotella melaninogenica/clasificación , Prevotella melaninogenica/genética , Análisis de Secuencia de ADN
12.
Oral Dis ; 20(7): 668-74, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24118283

RESUMEN

OBJECTIVE: To evaluate the ability of the probiotic strain Lactobacillus brevis CD2 to inhibit the opportunistic anaerobe Prevotella melaninogenica (PM1), a well-known causative agent of periodontitis. MATERIALS AND METHODS: The inhibitory effect of Lactobacillus CD2 on Prevotella PM1 biofilm was assessed both by exposing the anaerobe to the supernatant of the probiotic strain and by growing the two strains to obtain single or mixed biofilms. The inhibitory effect of CD2 on PM1 was also checked by the agar overlay method. RESULTS: The development of PM1 biofilm was strongly affected (56% decrease in OD value) by the CD2 supernatant after 96 h. A dose-dependent biofilm reduction was also observed at 1/10 and 1/100 dilutions of supernatant. Confocal microscopy on the mixed biofilms revealed the ability of CD2 to prevail on PM1, greatly reducing the biofilm of the latter. CONCLUSIONS: It has been hypothesized a multifactorial nature of the inhibition mechanism, the strong adherence ability of CD2 strain together with the released metabolites presumably contributing to the reduction in the PM1 biofilm detected by confocal microscopy.


Asunto(s)
Biopelículas , Levilactobacillus brevis/fisiología , Prevotella melaninogenica/fisiología , Probióticos , Fenómenos Fisiológicos Bacterianos
13.
Eur Arch Otorhinolaryngol ; 271(6): 1661-5, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24487459

RESUMEN

Although numerous studies based on the bacteriology of the tonsil have been carried out, none of them analyzed the variation of tonsillar flora with respect to both age and tonsillar size. The purpose of this study was to isolate the facultative and obligate anaerobes both from the surface and the core of tonsils in recurrent tonsillitis as well as to analyze the variation of isolated bacterial strains according to age and tonsillar size. A prospective study was performed on 111 patients who underwent tonsillectomy. We analyzed the differences between the bacterial pathogens in recurrent tonsillitis and semi-growth estimates with regard to age and tonsillar grade. Among 111 cases, 604 bacterial strains of 21 different from the tonsil superficial and core were isolated. The most common facultative anaerobic species isolated from the surface and core were Coagulase-negative staphylococci, Alpha-hemolytic streptococci and Diphtheroid bacilli in all subgroups except patients below 8 years old. The most commonly obligate anaerobic species isolated from the core were Propionibacterium acnes, Prevotella melaninogenica and Peptostreptococcus anaerobius. We found no significant difference in the cultured bacteria with respect to age and tonsillar size. The study subgroups did not differ in the occurrence of semiquantitative growth estimates of 3-4+. Our study demonstrates that there is polymicrobial aerobic and anaerobic flora in tonsils with regardless of patient's age and tonsillar size. This polymicrobial spectrum of bacteria may contribute to recurrence and to the failure of conservative treatment of these cases and therefore leads to surgical therapy.


Asunto(s)
Bacterias Anaerobias/aislamiento & purificación , Infecciones por Bacteroidaceae/microbiología , Infecciones por Bacterias Grampositivas/microbiología , Tonsila Palatina/microbiología , Infecciones Estafilocócicas/microbiología , Infecciones Estreptocócicas/microbiología , Tonsilitis/microbiología , Adolescente , Distribución por Edad , Factores de Edad , Bacterias/aislamiento & purificación , Infecciones por Bacteroidaceae/epidemiología , Niño , Femenino , Infecciones por Bacterias Grampositivas/epidemiología , Humanos , Masculino , Tamaño de los Órganos , Tonsila Palatina/patología , Tonsila Palatina/cirugía , Peptostreptococcus/aislamiento & purificación , Prevotella melaninogenica/aislamiento & purificación , Propionibacterium acnes/aislamiento & purificación , Infecciones Estafilocócicas/epidemiología , Staphylococcus/aislamiento & purificación , Infecciones Estreptocócicas/epidemiología , Streptococcus/aislamiento & purificación , Tonsilectomía , Tonsilitis/epidemiología , Tonsilitis/patología
14.
J Vis Exp ; (206)2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38709077

RESUMEN

Most in vitro models lack the capacity to fully probe bacterial phenotypes emerging from the complex interactions observed in real-life environments. This is particularly true in the context of hard-to-treat, chronic, and polymicrobial biofilm-based infections detected in the airways of individuals living with cystic fibrosis (CF), a multiorgan genetic disease. While multiple microbiome studies have defined the microbial compositions detected in the airway of people with CF (pwCF), no in vitro models thus far have fully integrated critical CF-relevant lung features. Therefore, a significant knowledge gap exists in the capacity to investigate the mechanisms driving the pathogenesis of mixed species CF lung infections. Here, we describe a recently developed four-species microbial community model, including Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus sanguinis, and Prevotella melaninogenica grown in CF-like conditions. Through the utilization of this system, clinically relevant phenotypes such as antimicrobial recalcitrance of several pathogens were observed and explored at the molecular level. The usefulness of this in vitro model resides in its standardized workflow that can facilitate the study of interspecies interactions in the context of chronic CF lung infections.


Asunto(s)
Biopelículas , Fibrosis Quística , Fenotipo , Fibrosis Quística/microbiología , Biopelículas/crecimiento & desarrollo , Humanos , Pseudomonas aeruginosa/fisiología , Staphylococcus aureus/fisiología , Staphylococcus aureus/genética , Microbiota/fisiología , Streptococcus sanguis/fisiología , Prevotella melaninogenica/genética
15.
Clin Oral Investig ; 17(2): 463-73, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22573244

RESUMEN

OBJECTIVES: This study aims to assess the effects of rinsing with zinc- and chlorhexidine-containing mouth rinse with or without adjunct tongue scraping on volatile sulfur compounds (VSCs) in breath air, and the microbiota at the dorsum of the tongue. MATERIAL AND METHODS: A randomized single-masked controlled clinical trial with a cross-over study design over 14 days including 21 subjects was performed. Bacterial samples from the dorsum of the tongue were assayed by checkerboard DNA-DNA hybridization. RESULTS: No halitosis (identified by VSC assessments) at day 14 was identified in 12/21 subjects with active rinse alone, in 10/21 with adjunct use of tongue scraper, in 1/21 for negative control rinse alone, and in 3/21 in the control and tongue scraping sequence. At day 14, significantly lower counts were identified only in the active rinse sequence (p < 0.001) for 15/78 species including, Fusobacterium sp., Porphyromonas gingivalis, Pseudomonas aeruginosa, Staphylococcus aureus, and Tannerella forsythia. A decrease in bacteria from baseline to day 14 was found in successfully treated subjects for 9/74 species including: P. gingivalis, Prevotella melaninogenica, S. aureus, and Treponema denticola. Baseline VSC scores were correlated with several bacterial species. The use of a tongue scraper combined with active rinse did not change the levels of VSC compared to rinsing alone. CONCLUSIONS: VSC scores were not associated with bacterial counts in samples taken from the dorsum of the tongue. The active rinse alone containing zinc and chlorhexidine had effects on intra-oral halitosis and reduced bacterial counts of species associated with malodor. Tongue scraping provided no beneficial effects on the microbiota studied. CLINICAL RELEVANCE: Periodontally healthy subjects with intra-oral halitosis benefit from daily rinsing with zinc- and chlorhexidine-containing mouth rinse.


Asunto(s)
Bacterias/efectos de los fármacos , Halitosis/microbiología , Lengua/microbiología , Adulto , Anciano , Antiinfecciosos Locales/uso terapéutico , Carga Bacteriana/efectos de los fármacos , Bacteroides/efectos de los fármacos , Bacteroides/aislamiento & purificación , Clorhexidina/uso terapéutico , Estudios Cruzados , Combinación de Medicamentos , Femenino , Estudios de Seguimiento , Fusobacterium/efectos de los fármacos , Fusobacterium/aislamiento & purificación , Halitosis/tratamiento farmacológico , Humanos , Sulfuro de Hidrógeno/análisis , Masculino , Persona de Mediana Edad , Antisépticos Bucales/uso terapéutico , Higiene Bucal/instrumentación , Porphyromonas gingivalis/efectos de los fármacos , Porphyromonas gingivalis/aislamiento & purificación , Prevotella melaninogenica/efectos de los fármacos , Prevotella melaninogenica/aislamiento & purificación , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/aislamiento & purificación , Método Simple Ciego , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación , Compuestos de Sulfhidrilo/análisis , Sulfuros/análisis , Lengua/efectos de los fármacos , Treponema denticola/efectos de los fármacos , Treponema denticola/aislamiento & purificación , Compuestos Orgánicos Volátiles/análisis , Adulto Joven , Acetato de Zinc/uso terapéutico
16.
J Periodontal Res ; 47(1): 95-104, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21895662

RESUMEN

BACKGROUND AND OBJECTIVE: The development of dental biofilms after professional plaque removal is very rapid. However, it is not clear whether most bacterial species return at similar rates in periodontally healthy and periodontitis subjects or if there are differences in bacterial recolonization between supragingival and subgingival biofilms in periodontal health and disease. MATERIAL AND METHODS: Supragingival and subgingival plaque samples were taken separately from 28 teeth in 38 healthy and 17 periodontitis subjects immediately after professional cleaning. Samples were taken again from seven teeth in randomly selected quadrants after 1, 2, 4 and 7 d of no oral hygiene and analyzed using checkerboard DNA-DNA hybridization. The percentage of DNA probe counts were averaged within subjects at each time-point. Ecological succession was determined using a modified moving-window analysis. RESULTS: Succession in supragingival biofilms from subjects with periodontitis and from healthy individuals was similar. At 1 d, Streptococcus mitis and Neisseria mucosa showed increased proportions, followed by Capnocytophaga gingivalis, Eikenella corrodens, Veillonella parvula and Streptococcus oralis at 1-4 d. At 4-7 d, Campylobacter rectus, Campylobacter showae, Prevotella melaninogenica and Prevotella nigrescens became elevated. Subgingival plaque redevelopment was slower and very different from supragingival plaque redevelopment. Increased proportions were first observed for S. mitis, followed by V. parvula and C. gingivalis and, at 7 d, by Capnocytophaga sputigena and P. nigrescens. No significant increase in the proportions of periodontal pathogens was observed in any of the clinical groups or locations. CONCLUSION: There is a defined order in bacterial species succession in early supragingival and subgingival biofilm redevelopment after professional cleaning.


Asunto(s)
Biopelículas/clasificación , Placa Dental/microbiología , Periodontitis/microbiología , Periodoncio/microbiología , Adulto , Carga Bacteriana , Campylobacter/clasificación , Campylobacter rectus/aislamiento & purificación , Capnocytophaga/clasificación , ADN Bacteriano/análisis , Placa Dental/terapia , Índice de Placa Dental , Profilaxis Dental , Raspado Dental , Eikenella corrodens/aislamiento & purificación , Femenino , Encía/microbiología , Humanos , Masculino , Interacciones Microbianas , Neisseria mucosa/aislamiento & purificación , Hibridación de Ácido Nucleico , Índice Periodontal , Prevotella melaninogenica/aislamiento & purificación , Prevotella nigrescens/aislamiento & purificación , Aplanamiento de la Raíz , Streptococcus mitis/aislamiento & purificación , Streptococcus oralis/aislamiento & purificación , Veillonella/aislamiento & purificación
17.
Clin Exp Dermatol ; 37(5): 501-4, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22212025

RESUMEN

Botryomycosis is an uncommon chronic suppurative granulomatous bacterial infection that can affect the skin and viscera. Clinically, lesions typically consist of small tender nodules from which draining sinuses may develop to expel a purulent discharge. Histopathological features include characteristic aggregation of microorganisms (grain) within the inflammatory infiltrate. The commonest causative organisms are Staphylococcus aureus and Pseudomonas aeruginosa, of others. Botryomycosis resulting from Prevotella melaninogenica has not been reported previously. We report the case of a middle-aged patient with botryomycosis presenting as nasal cutaneous fistulas caused by P. melaninogenica, which was successfully treated with surgical intervention combined with systemic antibiotic treatment.


Asunto(s)
Infecciones por Bacteroidaceae/complicaciones , Fístula Cutánea/microbiología , Enfermedades Nasales/microbiología , Prevotella melaninogenica/aislamiento & purificación , Antibacterianos/uso terapéutico , Infecciones por Bacteroidaceae/microbiología , Femenino , Humanos , Persona de Mediana Edad , Cavidad Nasal , Resultado del Tratamiento
19.
J Clin Pediatr Dent ; 36(3): 239-44, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22838224

RESUMEN

OBJECTIVE: The aim of this study was to evaluate in vitro the antimicrobial efficacy of a modified 3-mix paste and to compare it with an iodoform paste (Ultrapex) against anaerobic microorganisms isolated from root canals of infected or necrotic primary teeth. STUDY DESIGN: An in vitro experimental assay was performed over isolated and identified anaerobic microorganisms of 21 samples, in order to compare the antimicrobial ability of both root canal filling materials, using a disc-diffusion method. RESULTS: A total of 21 microbial samples (15 polymicrobial and 6 monomicrobial) were obtained, from which 19 different strains were identified. Modified 3-mix paste showed an excellent antimicrobial effect against most of both kinds of microbial samples, although some of them exhibited resistance; on the other hand, Ultrapex showed only minimal antimicrobial ability (null or low categories). Clostridium ramosum exhibited the most resistance to both materials. CONCLUSION: The bactericidal effect of the modified 3-mix paste was superior to Ultrapex, with a statistically significant difference, against anaerobic microorganisms isolated from infected root canals of primary teeth.


Asunto(s)
Antibacterianos/farmacología , Bacterias Anaerobias/efectos de los fármacos , Hidróxido de Calcio/farmacología , Cavidad Pulpar/microbiología , Materiales de Obturación del Conducto Radicular/farmacología , Siliconas/farmacología , Diente Primario/microbiología , Actinomyces/efectos de los fármacos , Infecciones Bacterianas/microbiología , Bacteroides/efectos de los fármacos , Bifidobacterium/efectos de los fármacos , Candida albicans/efectos de los fármacos , Ciprofloxacina/farmacología , Clostridium/efectos de los fármacos , Enfermedades de la Pulpa Dental/microbiología , Necrosis de la Pulpa Dental/microbiología , Combinación de Medicamentos , Farmacorresistencia Bacteriana , Gemella/efectos de los fármacos , Humanos , Ensayo de Materiales , Metronidazol/farmacología , Pruebas de Sensibilidad Microbiana , Minociclina/farmacología , Prevotella melaninogenica/efectos de los fármacos , Propionibacterium acnes/efectos de los fármacos , Streptococcus intermedius/efectos de los fármacos
20.
Implant Dent ; 20(6): 430-3, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22071498

RESUMEN

UNLABELLED: Maxillary sinus floor augmentation may have a variety of postoperative complications including infection, sequestration of bone, and maxillary sinusitis. Complications can also occur due to a preexisting sinus condition called ostium stenosis. This case report presents a complication after sinus lift and grafting procedure due to an unrecognized ostium stenosis. CASE REPORT: A 50-year-old male patient had sinus augmentation on his right side. However, postoperatively, his symptoms were protracted. A CT scan showed thickening of the Schneiderian membrane and scattered graft material. Management included endoscopic nasal examination and ostium enlargement, antibiotic coverage, and full enucleation of the graft and diseased tissue. CONCLUSION: Patency of the sinus ostium should be carefully evaluated before sinus lift/grafting procedure using CT technology. Radiology and otolaryngology consultations may be necessary to rule out ostium stenosis before surgery.


Asunto(s)
Seno Maxilar/patología , Elevación del Piso del Seno Maxilar/efectos adversos , Infección de la Herida Quirúrgica/terapia , Antibacterianos/uso terapéutico , Infecciones por Bacteroidaceae/diagnóstico , Trasplante Óseo/efectos adversos , Constricción Patológica/complicaciones , Constricción Patológica/cirugía , Endoscopía/métodos , Migración de Cuerpo Extraño/etiología , Humanos , Masculino , Seno Maxilar/cirugía , Sinusitis Maxilar/microbiología , Persona de Mediana Edad , Mucosa Nasal/patología , Obstrucción Nasal/etiología , Prevotella melaninogenica/aislamiento & purificación , Reoperación , Infección de la Herida Quirúrgica/microbiología , Tomografía Computarizada por Rayos X
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