16S rDNA-based metagenomic analysis of human oral plaque microbiota in patients with atherosclerosis and healthy controls.

To address the question if an altered oral microbiota is associated with atherosclerosis. Twenty patients suffering from atherosclerosis and 10 controls were recruited. Clinical oral, medical and laboratory investigations were performed. Oral bacteria were collected and 16S rDNA was sequenced following Single strand conformation polymorphism.(SSCP) Probing pocket depths in patients were significantly elevated. The oral microbiota of patients and controls were dominated by Fusobacterium (16%/17%), Streptococcus (21%/14%), Prevotella (10%/12%), Enterococcus (12%/12%), Porphyromonas (8%/7%), TM7 (0%/7%) and Veillonella (6%/7%). Differences in diversity were not significant between groups. The pathology of atherosclerosis may not be related to significant qualitative changes of the oral microbiota.

Regulación de la microbiota intestinal en voluntarios sanos mediante el consumo de un producto con el probiotico Lactobacillus johnsonii La1 / Regulation of the intestinal microbiota of healthy volunteers through the intake of the probiotic lactobacillus johnsonii la1

A basic mechanism implicated in the human health-promoting properties of probiotics is their ability to maintain the homeostasis of the intestinal microbiota. This study evaluates how the ingestion of different amounts of the probiotic Lactobacillus johnsonii La1 (La1) influences the main bacterial populations of the fecal microbiota. Eight asymptomatic volunteers participated in the study. After a basal period, they ingested 100 mL of a product containing 10(8) La1/mL during the first week, 200 mL during the second week and 500 ml during the third week. Fecal samples were obtained at the end of each period and during the 2 weeks post-ingestion. Lactobacilli were determined by culture on MRS agar and La1 colonies were confirmed by ERIC-PCR. The main populations of fecal bacteria were identified by fluorescent probes and flow cytometry. At baseline, 18.3 percent of the total fluorescent bacteria were F. praunitzii, 13.2 percent Bacteroides, 2.05 percent Bifidobacterium and 0.95 percent Lactobacillus. Fecal excretion of La1 increased during the ingestion period but it was cleared from the stools of the volunteers 2 weeks later. La1 intake increased the populations of Lactobacillus (p=0.056) and Bifidobacterium (p=0.067), which are considered as beneficial for the host, while it decreased those of F. prausnitzii (p=0.005) a potentially pathogenic microorganism. These bacterial populations returned to their baseline levels during the post-ingestion period. The regular intake of a La1-containing product beneficially affects the homeostasis of the human fecal microbiota probably contributing to the health-promoting effects of this probiotic.

Uno de los principales mecanismos implicados en las propiedades saludables de los probióticos es su capacidad de mantener la homeostasis de la microbiota intestinal. Este estudio evalúa cómo el consumo de distintas cantidades del probiótico Lactobacillus johnsonii La1 (La1) contribuye en la modulación de las principales poblaciones de la microbiota fecal. Ocho voluntarios asintomáticos participaron en el estudio. Después de un periodo basal, consumieron 100 mL de un producto que contenía 10(8) La1/mL durante la primera semana, 200 mL durante la segunda semana y 500 mL durante la tercera semana. Se obtuvieron muestras de deposición al final de cada uno de estos períodos y luego a los 7 y 14 días de haber terminado el consumo del producto. Las cantidades de lactobacilos excretados fueron determinadas por cultivo en agar MRS y las colonias de La1 fueron confirmadas por ERIC-PCR. Algunas de las principales poblaciones de bacterias fecales fueron evaluadas por hibridación in situ con sondas fluorescentes (FISH) y citometría de flujo. A nivel basal, 18.3 por ciento del número total de bacterias fluorescentes detectadas eran F. praunitzii,13.2 por ciento Bacteroides, 2.05 por ciento Bifidobacterium y 0.95 por ciento Lactobacillus. La excreción fecal de La1 aumentó durante el período de consumo pero desapareció después de 14 días de haber terminado el período de ingestión. El consumo de La1 aumentó las poblaciones de Lactobacillus (p=0.056) y Bifidobacterium (p=0.067) que son consideradas como beneficiosas para el huésped mientras que disminuyó aquella de F. prausnitzii (p=0.005), un microorganismo potencialmente patogénico. Las poblaciones bacterianas afectadas volvieron a sus niveles basales durante el periodo post-ingestión. Estos resultados indican que el consumo regular de La1 modula la homeostasis de la microbiota intestinal, lo cual contribuye probablemente a los efectos beneficiosos de este probiótico sobre la salud.

Detection and measurement of oral malodour in periodontitis patients.

BACKGROUND & OBJECTIVES: Malodour has been correlated with the concentration of volatile sulphur compounds produced in the oral cavity by metabolic activity of bacteria colonizing the periodontal sites and the dorsum of the tongue. The aim of this study was to detect malodour in mouth air organoleptically and using a portable sulphide monitor and to correlate it with the clinical parameters, halitosis linked toxins and BANA, using tongue and subgingival plaque samples. The halitosis grading is also correlated with the microbial colonies of the subgingival plaque sample. METHODS: 20 patients with chronic periodontitis with 5-7 mm pocket depth, radiographic evidence of bone loss and presence of oral malodour participated in this study. Assessment of mouth air was done organoleptically and by using a portable sulphide monitor. The clinical parameter, plaque index (PI), gingival index (GI), gingival bleeding index (BI), were obtained from all the areas. Samples for BANA and to detect halitosis linked toxins were taken from the dorsal surface of the tongue and periodontal pockets ranging 5-7 mm. Halitosis related microbial colonies were identified using anaerobic culturing from the subgingival plaque. RESULTS: The scores of PI, GI, BI and sample that tested positive for halitosis linked toxins and with the halitosis grading were not significant. The presence of tongue coating and the halitosis grading and toxin levels were significant. BANA has shown to be non contributory due to technical problems. Anaerobic culture has shown to identify Streptococcus, Bacteroides, Fusobacterium, Porphyromonas and Prevotella colonies. INTERPRETATION & CONCLUSION: The results confirmed that there was no correlation between the clinical parameters, halitosis linked toxins and halitosis grading. The microbial colonies have shown to correlate with the presence of oral malodour.

Role of non spore forming anaerobes in diarrheal diseases

The study included 40 diarrheic children under 3 years of age [20 acute and 20 chronic cases] and 20 age matched controls. Fecal specimens were collected from each. Isolation and characterization of non spore forming Gram-negative anaerobic rods was carried out by using non selective media [CDC and blood agar] and selective media [KVA and PVA] media, Gram stain, relationship to oxygen, fluorescence and spot tests. Presumptive identification was done by using several biochemical identification systems [presumpto plates, rapid enzyme systems and API 20 A]. Definitive identification was carried out by using gas liquid chromatography and toxin assays on B. fragilis isolates by using tissue culture cell lines [HELF and VERO] and by inoculation [intraperitoneal and intravenous] in 3-week old mice

Reporte de microorganismos aislados en 15 muestras de pulpas dentales necróticas / Report of microorganisms isolated from 15 samples of necrotic dental pulps

Es conocida la presencia de microorganismos en la cavidad bucal, estando descritos diferentes tipos de éstos en la literatura. La pulpa necrótica es un tejido muerto contenido en estructuras vivas. El conocimiento de los microorganismos presentes en las pulpas necróticas de la población en que se vive es de importancia profesional. El empleo de la antibioticoterapia es de importancia en la práctica diaria. En este estudio la penicilina y la clindamicina fueron los medicamentos de elección

Bacteriological study in overdenture wearer

Overdentures have gained high popularity in the last ten years as an alternative to complete dentures for patients with remaining natural teeth. The advantages of over denture were recorded as preserving the residual alveolar ridge, as well as increased masticatory performance due to the proprioceptive impulses from over denture abutments. [Lord and Teels., 1974 and Rissin et al., 1987]Many techniques for overdenture construction were used, but the most common techniques were that one constructed over reduced abutments with amallgum filling or over reduced abutments with cast metal or gold copings. The loss of abutments of the overdenture was the prime etiologic factor in overdenture failure, and that loss was often due to periodontal disease affecting the abutments. A question arise, dose the restorations for abutments of over dentures have an effect on the subgingival micro flora. The present work aims to study the effect amalgam and coping restoration of the abutments of overdenture on subgingival micro flora as well as the count of subgingival Bacteroides melaninigenicus