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1.
BMC Oral Health ; 23(1): 767, 2023 10 19.
Article de Anglais | MEDLINE | ID: mdl-37853400

RÉSUMÉ

BACKGROUND: Considered the most prevalent noncommunicable disease in childhood, dental caries is both an individual and a collective burden. While international guidelines highlight prevention as a major strategy for caries management in children, health professionals still struggle to implement prevention into their clinical practice. Further research is needed to understand the gap between the theoretical significance of dental prevention and its lack of implementation in the clinical setting. This systematic review aims to identify and classify factors perceived by health professionals to be barriers or facilitators to caries prevention in children. METHOD: A systematic literature search was conducted in three electronic databases (Medline, Web of Science and Cairn). Two researchers independently screened titles, abstracts and texts. To be selected, studies had to focus on barriers or facilitators to caries prevention in children and include health professionals as study participants. Qualitative and quantitative studies were selected. The factors influencing caries prevention in children were sorted into 3 main categories (clinician-related factors, patient-related factors, and organizational-related factors) and then classified according to the 14 domains of the theoretical domains framework (TDF). RESULTS: A total of 1771 references were found by combining manual and database searches. Among them, 26 studies met the inclusion criteria, of which half were qualitative and half were quantitative studies. Dentists (n = 12), pediatricians (n = 11), nurses (n = 9), and physicians (n = 5) were the most frequently interviewed health professionals in our analysis. Barriers and facilitators to caries prevention in children were categorized into 12 TDF domains. The most frequently reported domains were Environmental Context and Resources, Knowledge and Professional Role and Identity. CONCLUSION: This systematic review found that a wide range of factors influence caries prevention in children. Our analysis showed that barriers to pediatric oral health promotion affect all stages of the health care system. By highlighting the incompatibility between the health care system's organization and the implementation of caries prevention, this study aims to help researchers and policy-makers design new interventions to improve children's access to caries prevention. TRIAL REGISTRATION: PROSPERO CRD42022304545.


Sujet(s)
Caries dentaires , Humains , Enfant , Caries dentaires/prévention et contrôle , Susceptibilité à la carie dentaire , Personnel de santé , Santé buccodentaire , Promotion de la santé
2.
BMJ Open ; 12(12): e066680, 2022 12 01.
Article de Anglais | MEDLINE | ID: mdl-36455999

RÉSUMÉ

INTRODUCTION: Dental caries is one of the most common non-communicable diseases in children. The disease management of caries relies on both a preventive individual approach (fluoridation, risk evaluation) and the surgical treatment of established carious lesions. Similar to other non-communicable diseases (obesity, mental diseases, etc), health professionals' negative perceptions of patients have been shown to affect the quality of disease management. Regarding dental caries in children, some data have indicated the presence of discriminating beliefs and behaviours towards these children and their families in the medical setting. However, oral health stigma related to dental care remains a largely unexplored issue. METHODS AND ANALYSIS: This study presents an exploratory research protocol focusing on the perceptions and attitudes of health professionals towards children with early childhood caries (ECC) and their parents. Semistructured interviews will be conducted among medical and dental health professionals, and verbatim quotations obtained from audio transcriptions will be analysed to identify health professionals' perceptions of ECC and the influence of these perceptions on clinical care for these children. ETHICS AND DISSEMINATION: The research ethics committee of the Department of Family Medicine at University Lyon 1 approved this protocol. The results will be published in peer-reviewed journals and presented at scientific meetings. TRIAL REGISTRATION NUMBER: NCT05284279.


Sujet(s)
Caries dentaires , Maladies non transmissibles , Enfant d'âge préscolaire , Enfant , Humains , Caries dentaires/thérapie , Susceptibilité à la carie dentaire , Santé buccodentaire , Recherche qualitative
3.
J Clin Med ; 8(5)2019 May 26.
Article de Anglais | MEDLINE | ID: mdl-31130713

RÉSUMÉ

OBJECTIVE: Rheumatoid arthritis and periodontal disease are associated together, but the effect of therapy provided for one disease to the second one remained under-investigated. This study investigated effect of infliximab therapy used to treat rheumatoid arthritis (RA) on various biomarkers of periodontal disease (PD) severity including serologies of Porphyromonas gingivalis and Prevotella intermedia and matrix metalloproteinase 3. METHODS: Seventy nine RA patients were enrolled at the time to start infliximab therapy and the 28 joint disease activity score (DAS28), anti-cyclic citrullinated petides 2nd generation (anti-CCP2), anti-P. gingivalis antibody, and Matrix metalloproteinase 3 (MMP-3) were monitored before and at 6 months of infliximab therapy. Joint damage and severe periodontal disease were assessed at baseline. Anti-CCP2, anti-P. gingivalis antibody, and MMP-3 were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: At baseline, anti-CCP2 titers were associated with anti-P. gingivalis lipopolysaccharide (LPS)-specific antibodies titers (p < 0.05). Anti-P. gingivalis antibodies were not significantly correlated with clinical, biological, or destruction parameters of RA disease. At 6 months of infliximab therapy, MMP-3 level decreased (from 119 ± 103 ng/mL to 62.44 ± 52 ng/mL; p < 0.0001), whereas P. gingivalis antibody levels remained at the same level. DAS28 and inflammation markers C-reactive protein (CRP) and Erythrocyte sedimentation rate (ESR) also decreased significantly during infliximab therapy (p < 0.05) as anti-CCP2 levels (p < 0.001). Only high MMP-3 level at baseline was associated with infliximab efficacy (p < 0.01). CONCLUSION: MMP-3 level can be a useful marker of the efficacy of infliximab in RA patients. The treatment did not affect anti-P. gingivalis antibodies.

4.
Cost Eff Resour Alloc ; 16: 34, 2018.
Article de Anglais | MEDLINE | ID: mdl-30356786

RÉSUMÉ

BACKGROUND: The choice of cost data sources is crucial, because it influences the results of cost studies, decisions of hospital managers and ultimately national directives of policy makers. The main objective of this study was to compare a hospital cost accounting system in a French hospital group and the national cost study (ENC) considering the cost of organ recovery procedures. The secondary objective was to compare these approaches to the weighting method used in the ENC to assess organ recovery costs. METHODS: The resources consumed during the hospital stay and organ recovery procedure were identified and quantified retrospectively from hospital discharge abstracts and the national discharge abstract database. Identified items were valued using hospital cost accounting, followed by 2010-2011 ENC data, and then weighted using 2010-2011 ENC data. A Kruskal-Wallis test was used to determine whether at least two of the cost databases provided different results. Then, a Mann-Whitney test was used to compare the three cost databases. RESULTS: The costs assessed using hospital cost accounting differed significantly from those obtained using the ENC data (Mann-Whitney; P-value < 0.001). In the ENC, the mean costs for hospital stays and organ recovery procedures were determined to be €4961 (SD €7295) and €862 (SD €887), respectively, versus €12,074 (SD €6956) and €4311 (SD €1738) for the hospital cost accounting assessment. The use of a weighted methodology reduced the differences observed between these two data sources. CONCLUSIONS: Readers, hospital managers and decision makers must know the strengths and weaknesses of each database to interpret the results in an informed context.

5.
Eur J Public Health ; 28(3): 415-420, 2018 06 01.
Article de Anglais | MEDLINE | ID: mdl-29584911

RÉSUMÉ

Background: Organ recovery costs should be assessed to allow efficient and sustainable integration of these costs into national healthcare budgets and policies. These costs are of considerable interest to health economists, hospitals, financial managers and policy makers in most developed countries. This study assessed organ recovery costs from 2007 to 2014 in the French healthcare system based on the national hospital discharge database and a national cost study. The secondary objective was to describe the variability in the population of deceased organ donors during this period. Methods: All stays for organ recovery in French hospitals between January 2007 and December 2014 were quantified from discharge abstracts and valued using a national cost study. Five cost evaluations were conducted to explore all aspects of organ recovery activities. A sensitivity analysis was conducted to test the methodological choice. Trends regarding organ recovery practices were assessed by monitoring indicators. Results: The analysis included 12 629 brain death donors, with 28 482 organs recovered. The mean cost of a hospital stay was €7469 (SD = €10, 894). The mean costs of separate kidney, liver, pancreas, intestine, heart, lung and heart-lung block recovery regardless of the organs recovered were €1432 (SD = €1342), €502 (SD = €782), €354 (SD = €475), €362 (SD = €1559), €542 (SD = €955), €977 (SD = €1196) and €737 (SD = €637), respectively. Despite a marginal increase in donors, the number of organs recovered increased primarily due to improved practices. Conclusion: Although cost management is the main challenge for successful organ recovery, other aspects such as organization modalities should be considered to improve organ availability.


Sujet(s)
Prestations des soins de santé/économie , Prélèvement d'organes et de tissus/économie , Coûts et analyse des coûts , Femelle , France , Humains , Durée du séjour/économie , Mâle , Adulte d'âge moyen , Donneurs de tissus/statistiques et données numériques
6.
Health Econ Rev ; 6(1): 53, 2016 Dec.
Article de Anglais | MEDLINE | ID: mdl-27896782

RÉSUMÉ

BACKGROUND: The costing method used can change the results of economic evaluations. Choosing the appropriate method to assess the cost of organ recovery is an issue of considerable interest to health economists, hospitals, financial managers and policy makers in most developed countries. OBJECTIVES: The main objective of this study was to compare a mixed method, combining top-down microcosting and bottom-up microcosting versus full top-down microcosting to assess the cost of organ recovery in a French hospital group. The secondary objective was to describe the cost of kidney, liver and pancreas recovery from French databases using the mixed method. METHODS: The resources consumed for each donor were identified and valued using the proposed mixed method and compared to the full top-down microcosting approach. Data on kidney, liver and pancreas recovery were collected from a medico-administrative French database for the years 2010 and 2011. Related cost data were recovered from the hospital cost accounting system database for 2010 and 2011. Statistical significance was evaluated at P < 0.05. RESULTS: All the median costs for organ recovery differ significantly between the two costing methods (non-parametric test method; P < 0.01). Using the mixed method, the median cost for recovering kidneys was found to be €5155, liver recovery was €2528 and pancreas recovery was €1911. Using the full top-down microcosting method, median costs were found to be 21-36% lower than with the mixed method. CONCLUSION: The mixed method proposed appears to be a trade-off between feasibility and accuracy for the identification and valuation of cost components when calculating the cost of organ recovery in comparison to the full top-down microcosting approach.

7.
ScientificWorldJournal ; 2014: 924741, 2014.
Article de Anglais | MEDLINE | ID: mdl-25401161

RÉSUMÉ

OBJECTIVES: The aim of this study was to evaluate a light-emitting diode fluorescence tool, the SOPROLIFE light-induced fluorescence evaluator, and compare it to the international caries detection and assessment system-II (ICDAS-II) in the detection of occlusal caries. METHODS: A total of 219 permanent posterior teeth in 21 subjects, with age ranging from 15 to 65 years, were examined. An intraclass correlation coefficient (ICC) was computed to assess the reliability between the two diagnostic methods. RESULTS: The results showed a high reliability between the two methods (ICC = 0.92; IC = 0.901-0.940; P < 0.001). The SOPROLIFE blue fluorescence mode had a high sensitivity (87%) and a high specificity (99%) when compared to ICDAS-II. CONCLUSION: Compared to the most used visual method in the diagnosis of occlusal caries lesions, the finding from this study suggests that SOPROLIFE can be used as a reproducible and reliable assessment tool. At a cut-off point, categorizing noncarious lesions and visual change in enamel, SOPROLIFE shows a high sensitivity and specificity. We can conclude that financially ICDAS is better than SOPROLIFE. However SOPROLIFE is easier for clinicians since it is a simple evaluation of images. Finally in terms of efficiency SOPROLIFE is not superior to ICDAS but tends to be equivalent with the same advantages.


Sujet(s)
Caries dentaires/diagnostic , Imagerie optique/méthodes , Imagerie optique/normes , Adolescent , Adulte , Sujet âgé , Lampes à photopolymériser dentaires , Émail dentaire/anatomopathologie , Femelle , Fluorescence , Humains , Mâle , Adulte d'âge moyen , Jeune adulte
8.
Restor Dent Endod ; 38(4): 258-62, 2013 Nov.
Article de Anglais | MEDLINE | ID: mdl-24303363

RÉSUMÉ

The restorative management of deep carious lesions and the preservation of pulp vitality of immature teeth present real challenges for dental practitioners. New tricalcium silicate cements are of interest in the treatment of such cases. This case describes the immediate management and the follow-up of an extensive carious lesion on an immature second right mandibular premolar. Following anesthesia and rubber dam isolation, the carious lesion was removed and a partial pulpotomy was performed. After obtaining hemostasis, the exposed pulp was covered with a tricalcium silicate cement (Biodentine, Septodont) and a glass ionomer cement (Fuji IX extra, GC Corp.) restoration was placed over the tricalcium silicate cement. A review appointment was arranged after seven days, where the tooth was asymptomatic with the patient reporting no pain during the intervening period. At both 3 and 6 mon follow up, it was noted that the tooth was vital, with normal responses to thermal tests. Radiographic examination of the tooth indicated dentin-bridge formation in the pulp chamber and the continuous root formation. This case report demonstrates a fast tissue response both at the pulpal and root dentin level. The use of tricalcium silicate cement should be considered as a conservative intervention in the treatment of symptomatic immature teeth.

9.
Eur J Oral Sci ; 121(4): 341-8, 2013 Aug.
Article de Anglais | MEDLINE | ID: mdl-23841786

RÉSUMÉ

The objective of this study was to address the following question: 'Which properties are modified in partially demineralized surfaces, compared with non-demineralized dentin surfaces, following orthophosphoric acid-etching as performed in clinical procedures?'. For this purpose, the complementary techniques atomic force microscopy/spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and contact angle measurements were used to provide a multiscale characterization of the dentin substrate undergoing the acidic preconditioning designed to enhance wetting. Special attention was given to the influence of the etching pretreatment on the nanomechanical properties at different levels of dentin surfaces, in both dry and hydrated conditions. The four-sided pyramid model (extended Hertz contact model) proved to be accurate for calculating the apparent Young's modulus, offering new information on the elasticity of dentin. The modulus value notably decreased following etching and surface hydration. This study underlines that after the acid etching pretreatment the contribution of the nanomechanical, morphological, and physicochemical modifications has a strong influence on the dentin adhesion properties and thus plays a significant role in the coupling of the adhesive-resin composite build-up material at the dentin surface.


Sujet(s)
Mordançage à l'acide , Dentine/composition chimique , Module d'élasticité , Acides phosphoriques/effets indésirables , Propriétés de surface , Déminéralisation dentaire/induit chimiquement , Humains , Microscopie à force atomique , Microscopie électronique à balayage , Dent de sagesse , Spectrométrie d'émission X
10.
J Adhes Dent ; 14(5): 433-46, 2012 Aug.
Article de Anglais | MEDLINE | ID: mdl-23082311

RÉSUMÉ

PURPOSE: The aim of this literature review was to investigate the results from in vitro laboratory studies on the influence of temperature and relative humidity present before polymerization on enamel and dentin bonding systems. MATERIALS AND METHODS: A systematic search was carried out including articles published in English, in peer reviewed journals, and indexed in MEDLINE/PubMed database. The search was carried out using the terms: relative AND humidity AND dental. In vitro studies were retrieved and divided into laboratory simulation studies and studies on physical properties. Laboratory simulation studies were addressed by subtopic: resin-enamel bond strength, resin-dentin bond strength, and dentin-enamel microleakage. Studies on physical properties tested the influence of humidity and temperature through polymerization contraction, flexural strength, and dentin wettability. RESULTS: Laboratory simulation studies demonstrated a strong influence of humidity and temperature on dentin and enamel bond strength and microleakage with dental adhesives systems. The studies on physical properties failed to demonstrate any influence of humidity on the adhesion performance, except for wettability measurement. CONCLUSION: The clinical relevance of these in vitro results remains to be demonstrated. A review of in vivo clinical studies will complete the literature data presented here.


Sujet(s)
Collage dentaire/méthodes , Ciments dentaires/composition chimique , Émail dentaire/ultrastructure , Dentine/ultrastructure , Percolation dentaire/classification , Humains , Humidité , Test de matériaux/méthodes , Polymérisation , Contrainte mécanique , Propriétés de surface , Température
11.
Int Dent J ; 62(1): 33-9, 2012 Feb.
Article de Anglais | MEDLINE | ID: mdl-22251035

RÉSUMÉ

AIM: To assess the effectiveness of mineral trioxide aggregate (MTA) used as an indirect pulp-capping material in human molar and premolar teeth. METHODOLOGY: We conducted a clinical evaluation of 60 teeth, which underwent an indirect pulp-capping procedure with either MTA or calcium hydroxide cement (Dycal(®) ). Calcium hydroxide was compared with MTA and the thickness of the newly formed dentine was measured at regular time intervals. The follow-up was at 3 and 6 months, and dentine formation was monitored by radiological measurements on digitised images using Mesurim Pro(®) software. RESULTS: At 3 months, the clinical success rates of MTA and calcium hydroxide were 93% and 73%, respectively (P = 0.02). At 6 months, the success rate was 89.6% with MTA, and remained steady at 73% with calcium hydroxide (P = 0.63). The mean initial residual dentine thickness was 0.23 mm, and increased by 0.121 mm with MTA and by 0.136 mm with calcium hydroxide at 3 months. At 6 months, there was an increase of 0.235 mm with MTA and of 0.221 mm with calcium hydroxide. CONCLUSIONS: A higher success rate was observed in the MTA group relative to the Dycal(®) group after 3 months, which was statistically significant. After 6 months, no statistically significant difference was found in the dentine thickness between the two groups. Additional histological investigations are needed to support these findings.


Sujet(s)
Composés de l'aluminium/usage thérapeutique , Composés du calcium/usage thérapeutique , Hydroxyde de calcium/usage thérapeutique , Coiffage pulpaire/méthodes , Dentine secondaire/métabolisme , Minéraux/usage thérapeutique , Oxydes/usage thérapeutique , Agents de coiffage pulpaire et de pulpectomie/usage thérapeutique , Silicates/usage thérapeutique , Adolescent , Adulte , Composés de l'aluminium/pharmacologie , Prémolaire , Composés du calcium/pharmacologie , Hydroxyde de calcium/pharmacologie , Pulpe dentaire/effets des médicaments et des substances chimiques , Dentine secondaire/croissance et développement , Association médicamenteuse , Femelle , Humains , Modèles logistiques , Mâle , Minéraux/pharmacologie , Molaire , Oxydes/pharmacologie , Études prospectives , Agents de coiffage pulpaire et de pulpectomie/pharmacologie , Silicates/pharmacologie , Méthode en simple aveugle , Jeune adulte
12.
J Nanosci Nanotechnol ; 9(1): 467-74, 2009 Jan.
Article de Anglais | MEDLINE | ID: mdl-19441336

RÉSUMÉ

Poly(lactic-co-glycolic acid) particles encapsulating albumin were produced by the double emulsion technique (Water in Oil in Water). The diffusion coefficient and therefore the release rate were quantified as a function of the operating conditions. The second Fick's law of diffusion was used by applying the entire particle size distribution to estimate the diffusion coefficient. The stirring speed, polyvinyl alcohol concentration in the external water phase and the water to oil ratio in the internal emulsion were varied. It was found that the release rate increased while decreasing the particle size. Therefore, all the process parameters that are assumed to affect the particles size--such as the stirring speed or marginally the polyvinyl alcohol concentration--are supposed to affect the release rate. Finally, decreasing the water to oil ratio in the internal emulsion was found to increase the particle porosity and therefore to increase the diffusion coefficient.


Sujet(s)
Préparations à action retardée/composition chimique , Vecteurs de médicaments/composition chimique , Préparation de médicament/méthodes , Modèles chimiques , Préparations pharmaceutiques/composition chimique , Simulation numérique , Diffusion , Cinétique
13.
Eur J Oral Sci ; 116(1): 77-82, 2008 Feb.
Article de Anglais | MEDLINE | ID: mdl-18186736

RÉSUMÉ

The purpose of this study was to investigate the role of light parameters on nanohybrid composite curing. Two nanohybrid resins were cured by two light-emitting diode (LED) devices and by one quartz-tungsten-halogen (QTH) device using different combinations of energy density and power density (8 J cm(-2) and 400 mW cm(-2); 8 J cm(-2) and 1,000 mW cm(-2); 16 J cm(-2) and 400 mW cm(-2); and 16 J cm(-2)-1,000 mW cm(-2)). The effects of these combinations on polymerization were assessed by measuring the Vickers microhardness. Data differed for the two composites and varied according to the light parameters and the nature of the curing device. For both resins, an energy density of 16 J cm(-2) yielded the best microhardness values at both the top and the bottom of the sample, independently of the power density. When using a lower energy density of 8 J cm(-2), a modulated power density was required to achieve proper curing at the bottom of the sample: 8 J cm(-2) and 400 mW cm(-2) induced greater values at the bottom surface. At an energy density of 16 J cm(-2), the power density was not relevant (no significant differences were found between 400 and 1,000 mW cm(-2)), except when the emission spectra of the light-curing units (LCUs) did not match exactly with the absorption spectra of the photoinitators included in the resins (greatest values with 16 J cm(-2) and 1,000 mW cm(-2)). These results suggest that above a certain energy density threshold, the power density may not significantly influence the polymerization kinetics.


Sujet(s)
Matériaux dentaires/effets des radiations , Lumière , Nanocomposites/effets des radiations , Polymères/effets des radiations , Halogènes , Dureté/effets des radiations , Essais de dureté , Cinétique , Test de matériaux , Nanocomposites/composition chimique , Spectrophotométrie
14.
Biomaterials ; 28(4): 632-40, 2007 Feb.
Article de Anglais | MEDLINE | ID: mdl-17049374

RÉSUMÉ

Polyethyleneimine (PEI) is a synthetic polymer commonly used as precursor base layer in polyelectrolyte multilayer films. However, the biological properties of this cationic macromolecule are poorly understood. The aim of this experimental investigation was to evaluate in vitro the biocompatibility of PEI towards two different human cell lines. The experimental investigation was undertaken on pure titanium (Ti) and nickel-titanium (NiTi) alloy samples with an average surface roughness of Ra=0.3microm. A biological study was undertaken at day 0 (2h after seeding), day 2, day 4 and day 7 to observe the cellular response of fibroblasts and osteoblasts cell lines in terms of morphology, adhesion (as observed by scanning electron microscopy), and viability (Mosmann's test). The results showed that PEI can be successfully deposited onto Ti or NiTi alloy, but generates a detrimental cellular response on both substrates as illustrated by a decrease of both fibroblast and osteoblast adhesion and proliferation over a 7-day culture period. These results suggest that PEI is potentially cytotoxic and may not be biocompatible enough in clinical applications using high molecular weight. As a consequence, polyelectrolyte multilayer films, which are promising in prosthesis and implantology fields, could not be coated with PEI at a high molecular weight. A lower molecular weight should be considered or a more biocompatible molecular base as precursor layer of polyelectrolyte multilayer films would be better to use for a good human bio-integration.


Sujet(s)
Électrolytes/toxicité , Polyéthylèneimine/toxicité , Forme de la cellule/effets des médicaments et des substances chimiques , Survie cellulaire/effets des médicaments et des substances chimiques , Cellules cultivées , Humains , Microscopie électronique à balayage , Ostéoblastes/cytologie , Ostéoblastes/effets des médicaments et des substances chimiques
15.
Pediatr Nephrol ; 21(6): 851-5, 2006 Jun.
Article de Anglais | MEDLINE | ID: mdl-16703377

RÉSUMÉ

To outline the specific oral surveillance needs of renal transplant children, we report the 4-year follow-up data of 106 children examined routinely on a 6-month basis and upon request from the medical team or the parents in the interval. Data were recorded for hard and soft dental tissues, including enamel defects carious lesions, gingival status, orthodontic treatment needs, and wisdom teeth eruption. Hard-tissue lesions were noted in 34.9% of the children, caries lesions on the permanent teeth were seen in 15.0% of cases, 18.86% of the patients had orthodontic treatment. Spontaneous examination, upon request for medical reasons, was given for 26 children. Twenty-one demands originated from the parents. Over a 4-year period the attendance of a dental specialist resulted in a significant improvement in the oral health of the renal transplant children.


Sujet(s)
Transplantation rénale , Santé buccodentaire , Maladies parodontales/épidémiologie , Surveillance de la population , Maladies des dents/épidémiologie , Adolescent , Enfant , Femelle , Humains , Mâle
16.
Appl Environ Microbiol ; 71(1): 282-9, 2005 Jan.
Article de Anglais | MEDLINE | ID: mdl-15640199

RÉSUMÉ

We used gene sequencing to determine whether clinical (sporadic, epidemic, and endemic) and environmental isolates of Legionella pneumophila serogroup (sg) 1 belong to specific lineages. A total of 178 clinical and environmental L. pneumophila sg 1 isolates, defined by pulsed-field gel electrophoresis and epidemiological data as sporadic, epidemic, or endemic, were analyzed for polymorphisms in five gene fragments. The fragments belonged to three housekeeping genes (coding for aconitase [acn], aspartate-beta-semialdehyde dehydrogenase [asd], and RNA polymerase beta subunit [rpoB]) and two surface protein genes (coding for the macrophage infectivity potentiator [mip] and the major outer membrane protein [mompS]). The phylogenetic tree inferred from sequence polymorphisms of the five genes identified two large clusters, one consisting of 133 poorly differentiated strains and containing two smaller clusters (10 and 2 strains) unrelated to each other and the other consisting of 42 strains. Clinical and environmental isolates could not be distinguished on this basis, and no link between genetic background and epidemiological type was found, suggesting that other factors are responsible for differences in pathogenicity.


Sujet(s)
Protéines bactériennes/génétique , Legionella pneumophila/classification , Maladie des légionnaires/microbiologie , Analyse de séquence d'ADN , Microbiologie de l'eau , Protéines bactériennes/composition chimique , Techniques de typage bactérien , Séquence nucléotidique , Hôpitaux , Humains , Legionella pneumophila/génétique , Legionella pneumophila/isolement et purification , Données de séquences moléculaires , Phylogenèse , Alimentation en eau
17.
Appl Environ Microbiol ; 70(3): 1651-7, 2004 Mar.
Article de Anglais | MEDLINE | ID: mdl-15006790

RÉSUMÉ

A new method for the rapid and sensitive detection of Legionella pneumophila in hot water systems has been developed. The method is based on an IF assay combined with detection by solid-phase cytometry. This method allowed the enumeration of L. pneumophila serogroup 1 and L. pneumophila serogroups 2 to 6, 8 to 10, and 12 to 15 in tap water samples within 3 to 4 h. The sensitivity of the method was between 10 and 100 bacteria per liter and was principally limited by the filtration capacity of membranes. The specificity of the antibody was evaluated against 15 non-Legionella strains, and no cross-reactivity was observed. When the method was applied to natural waters, direct counts of L. pneumophila were compared with the number of CFU obtained by the standard culture method. Direct counts were always higher than culturable counts, and the ratio between the two methods ranged from 1.4 to 325. Solid-phase cytometry offers a fast and sensitive alternative to the culture method for L. pneumophila screening in hot water systems.


Sujet(s)
Numération de colonies microbiennes/méthodes , Legionella pneumophila/isolement et purification , Microbiologie de l'eau , Numération de colonies microbiennes/statistiques et données numériques , Technique d'immunofluorescence , Température élevée , Legionella pneumophila/immunologie , Sensibilité et spécificité , Spécificité d'espèce , Coloration et marquage/méthodes
18.
J Clin Microbiol ; 41(7): 3320-2, 2003 Jul.
Article de Anglais | MEDLINE | ID: mdl-12843082

RÉSUMÉ

An analysis of 691 French clinical Legionella isolates showed that the endemic L. pneumophila serogroup 1 strain Paris was responsible for 12.2% of all cases of legionellosis and had a specific pulsed-field gel electrophoresis pattern. We also demonstrated the presence of this endemic clone throughout Europe.


Sujet(s)
Maladies endémiques , Legionella pneumophila/classification , Maladie des légionnaires/épidémiologie , Techniques de typage bactérien , Type II site-specific deoxyribonuclease , Électrophorèse en champ pulsé , France/épidémiologie , Humains , Maladie des légionnaires/microbiologie , Sérotypie
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