24 research outputs found
On weighted Adams-Bashforth rules
One class of the linear multistep methods for solving the Cauchy problems of the form , , contains Adams-Bashforth rules of the form , where are fixed numbers. In this paper, we propose an idea for weighted type of Adams-Bashforth rules for solving the Cauchy problem for singular differential equations,[A(x)y\u27+B(x)y=G(x,y), quad y(x_0)=y_0,]where and are two polynomials determining the well-known classical weight functions in the theory of orthogonal polynomials. Some numerical examples are also included
Lipoteichoic acid stimulates the proliferation, migration and cytokine production of adult dental pulp stem cells without affecting osteogenic differentiation
Aim: To model in vitro the contact between adult dental pulp stem cells (DPSCs) and lipoteichoic acid (LTA), a cell wall component expressed at the surface of most Gram-positive bacteria. Methodology: Human DPSCs obtained from impacted third molars were cultured and exposed to various concentrations of S. aureus LTA (0.1, 1.0 and 10 ”g mL â1). The effects of LTA on DPSCs proliferation and apoptosis were investigated by MTT assay and flow cytometry. Mineralization of DPSCs was evaluated by alizarin red staining assay. Migration was investigated by microphotographs of wound-healing and Transwell migration assays. Reverse transcription polymerase chain reaction was used to examine the effects of LTA on p65 NF-ÎșB translocation and TLR1, TLR2 or TLR6 regulation. Enzyme-linked immunosorbent assay was used to investigate LTA-stimulated DPSCs cytokine production. One-way or two-way ANOVA and Tukey post hoc multiple comparison were used for statistical analysis. Results: DPSCs expressed TLR1, TLR2 and TLR6 involved in the recognition of various forms of LTA or lipoproteins. Exposure to LTA did not up- or down-regulate the mRNAs of TLR1, TLR2 or TLR6 whilst LPS acted as a potent inducer of them [TLR1 (P â€Â 0.05), TLR2 (P â€Â 0.001) and TLR6 (P â€Â 0.001)]. Translocation of p65 NF-ÎșB to the nucleus was detected in LTA-stimulated cells, but to a lesser extent than LPS-stimulated DPSCs (P â€Â 0.001). The viability of cells exposed to LTA was greater than unstimulated cells, which was attributed to an increased proliferation and not to less cell death [LTA 1 Όg mL â1 (P â€Â 0.001) and 10 Όg mL â1 (P â€Â 0.01)]. For specific doses of LTA (1.0 ”g mL â1), adhesion of DPSCs to collagen matrix was disturbed (P â€Â 0.05) and cells enhanced their horizontal mobility (P â€Â 0.001). LTA-stimulated DPSCs released IL-6 and IL-8 in a dose-dependent manner (P â€Â 0.0001). At all concentrations investigated, LTA did not influence osteogenic/odontoblastic differentiation. Conclusions: Human DPSCs were able to sense the wall components of Gram-positive bacteria likely through TLR2 signalling. Consequently, cells modestly proliferated, increased their migratory behaviour and contributed significantly to the local inflammatory response through cytokine release. </p
Les matériaux d'obturation et de coiffage pulpaire des dents lactéales
Les soins pulpaires en denture lactĂ©ale sont les soins frĂ©quemment rĂ©alisĂ©s en odontologie pĂ©diatrique et la rĂ©action pulpaire ainsi que les mĂ©canismes de rĂ©paration tissulaire lors dâun traumatisme ne sont pas trĂšs bien connus ou investiguĂ©s. En se rĂ©fĂ©rant Ă la littĂ©rature dentaire, on constate que les recherches sont souvent focalisĂ©es sur la denture dĂ©finitive.<p>Objectifs<p>1) Etudier lâinfluence du traitement avec divers matĂ©riaux sur la formation dentinaire, la structure tissulaire et le degrĂ© dâinflammation.<p>2) AcquĂ©rir des connaissances sur lâinteraction Ă lâinterface matĂ©riau/tissu.<p>3) Etudier le rĂŽle de la voie de signalisation Notch (1 et 2) dans le processus de remaniement et rĂ©paration du tissu pulpaire en cas de traumatisme.<p>MatĂ©riels et mĂ©thodes<p>Deux types de soins pulpaires, la pulpotomie et le coiffage direct, sont rĂ©alisĂ©s sur les dents lactĂ©ales porcines et les rĂ©sultats sont Ă©tudiĂ©s aprĂšs 3 pĂ©riodes :7 jours, 21-28 jours et 90 jours.<p>La pulpotomie :8 matĂ©riaux, 10 dents par matĂ©riau, 2 matĂ©riaux par cochon et par pĂ©riode pour un total de 240 dents.<p>Le coiffage direct :10 matĂ©riaux, 10 dents par matĂ©riau, 2 matĂ©riaux par cochon et par pĂ©riode pour un total de 300 dents.<p>Par la suite, diffĂ©rentes techniques ont Ă©tĂ© utilisĂ©es :<p>1. La microscopie optique :Ă©tude des coupes histologiques aprĂšs coloration.<p>2. La microscopie Ă©lectronique Ă transmission :observer les caractĂ©ristiques morphologiques du tissu pulpaire et analyser les structures cellulaires en dĂ©tail. Lâobjectif principal de cette recherche Ă©tait centrĂ© sur les biomatĂ©riaux pour la pĂ©riode de 21-28 jours afin dâexaminer lâinteraction entre le biomatĂ©riau et le complexe dentino-pulpaire aprĂšs leur placement.<p>12<p>3. La voie de signalisation Notch (1 et 2): investiguer lâintervention Ă©ventuelle de cette voie dans le processus de rĂ©gĂ©nĂ©ration tissulaire par diffĂ©renciation des cellules pour les deux pĂ©riodes de 7 et 21-28 jours pour tous les matĂ©riaux utilisĂ©s.<p>RĂ©sultats<p>A. Microscopie optique :<p>1. La pulpotomie :les biomatĂ©riaux provoquent moins dâinfiltrat de cellules inflammatoires au niveau du tissu pulpaire et favorisent la dĂ©position dentinaire.<p>2. Le coiffage direct :on obtient les mĂȘmes rĂ©sultats que dans le cadre de la pulpotomie.<p>B. Microscopie Ă©lectronique en transmission :<p>1. Lâinduction du tissu calcifiĂ© ou la formation de nĂ©o-dentine sâest seulement produite au niveau du site de lâexposition aprĂšs le placement des biomatĂ©riaux dans les 2 types du traitement (pulpotomie & coiffage direct). En revanche aucune formation du tissu calcifiĂ© nâa Ă©tĂ© observĂ©e dans le parenchyme pulpaire Ă distance du site de lâexposition.<p>2. Cet examen montre que les cellules en contact des biomatĂ©riaux ou mĂȘme Ă proximitĂ© de ces derniers prĂ©sentent un rĂ©ticulum endoplasmique Ă©largi parallĂšle Ă la longueur de la cellule. Des mitochondries, plusieurs appareils de Golgi et des Ă©lĂ©ments denses sont observĂ©s dans le cytoplasme cellulaire.<p>3. Cet examen a Ă©galement montrĂ© que le MTA et le WPC, considĂ©rĂ©s par la littĂ©rature dentaire comme non-rĂ©sorbables, sont phagocytĂ©s par les cellules histiocytaires.<p>C. Voie de signalisation de Notch :<p>Nos recherches nâont pas montrĂ© de marquage concluant pour aucun de matĂ©riaux sauf dans le cadre de coiffage direct pour les dents traitĂ©es au MTA et Ca(OH)2 pour la pĂ©riode de 7 jours. Par contre, aucun marquage nâest observĂ© aprĂšs 21-28 jours.Doctorat en Sciences dentairesinfo:eu-repo/semantics/nonPublishe
Les matériaux d'obturation et de coiffage pulpaire des dents lactéales
Les soins pulpaires en denture lactĂ©ale sont les soins frĂ©quemment rĂ©alisĂ©s en odontologie pĂ©diatrique et la rĂ©action pulpaire ainsi que les mĂ©canismes de rĂ©paration tissulaire lors dâun traumatisme ne sont pas trĂšs bien connus ou investiguĂ©s. En se rĂ©fĂ©rant Ă la littĂ©rature dentaire, on constate que les recherches sont souvent focalisĂ©es sur la denture dĂ©finitive.Objectifs1) Etudier lâinfluence du traitement avec divers matĂ©riaux sur la formation dentinaire, la structure tissulaire et le degrĂ© dâinflammation.2) AcquĂ©rir des connaissances sur lâinteraction Ă lâinterface matĂ©riau/tissu.3) Etudier le rĂŽle de la voie de signalisation Notch (1 et 2) dans le processus de remaniement et rĂ©paration du tissu pulpaire en cas de traumatisme.MatĂ©riels et mĂ©thodesDeux types de soins pulpaires, la pulpotomie et le coiffage direct, sont rĂ©alisĂ©s sur les dents lactĂ©ales porcines et les rĂ©sultats sont Ă©tudiĂ©s aprĂšs 3 pĂ©riodes :7 jours, 21-28 jours et 90 jours.La pulpotomie :8 matĂ©riaux, 10 dents par matĂ©riau, 2 matĂ©riaux par cochon et par pĂ©riode pour un total de 240 dents.Le coiffage direct :10 matĂ©riaux, 10 dents par matĂ©riau, 2 matĂ©riaux par cochon et par pĂ©riode pour un total de 300 dents.Par la suite, diffĂ©rentes techniques ont Ă©tĂ© utilisĂ©es :1. La microscopie optique :Ă©tude des coupes histologiques aprĂšs coloration.2. La microscopie Ă©lectronique Ă transmission :observer les caractĂ©ristiques morphologiques du tissu pulpaire et analyser les structures cellulaires en dĂ©tail. Lâobjectif principal de cette recherche Ă©tait centrĂ© sur les biomatĂ©riaux pour la pĂ©riode de 21-28 jours afin dâexaminer lâinteraction entre le biomatĂ©riau et le complexe dentino-pulpaire aprĂšs leur placement.123. La voie de signalisation Notch (1 et 2): investiguer lâintervention Ă©ventuelle de cette voie dans le processus de rĂ©gĂ©nĂ©ration tissulaire par diffĂ©renciation des cellules pour les deux pĂ©riodes de 7 et 21-28 jours pour tous les matĂ©riaux utilisĂ©s.RĂ©sultatsA. Microscopie optique :1. La pulpotomie :les biomatĂ©riaux provoquent moins dâinfiltrat de cellules inflammatoires au niveau du tissu pulpaire et favorisent la dĂ©position dentinaire.2. Le coiffage direct :on obtient les mĂȘmes rĂ©sultats que dans le cadre de la pulpotomie.B. Microscopie Ă©lectronique en transmission :1. Lâinduction du tissu calcifiĂ© ou la formation de nĂ©o-dentine sâest seulement produite au niveau du site de lâexposition aprĂšs le placement des biomatĂ©riaux dans les 2 types du traitement (pulpotomie & coiffage direct). En revanche aucune formation du tissu calcifiĂ© nâa Ă©tĂ© observĂ©e dans le parenchyme pulpaire Ă distance du site de lâexposition.2. Cet examen montre que les cellules en contact des biomatĂ©riaux ou mĂȘme Ă proximitĂ© de ces derniers prĂ©sentent un rĂ©ticulum endoplasmique Ă©largi parallĂšle Ă la longueur de la cellule. Des mitochondries, plusieurs appareils de Golgi et des Ă©lĂ©ments denses sont observĂ©s dans le cytoplasme cellulaire.3. Cet examen a Ă©galement montrĂ© que le MTA et le WPC, considĂ©rĂ©s par la littĂ©rature dentaire comme non-rĂ©sorbables, sont phagocytĂ©s par les cellules histiocytaires.C. Voie de signalisation de Notch :Nos recherches nâont pas montrĂ© de marquage concluant pour aucun de matĂ©riaux sauf dans le cadre de coiffage direct pour les dents traitĂ©es au MTA et Ca(OH)2 pour la pĂ©riode de 7 jours. Par contre, aucun marquage nâest observĂ© aprĂšs 21-28 jours.Doctorat en Sciences dentairesinfo:eu-repo/semantics/nonPublishe
Assessment of microleakage of class V restored by resin composite and resin-modified glass ionomer and pit and fissure resin-based sealants following Er:YAG laser conditioning and acid etching: In vitro study
Aim: The aim of this study was to make a comparison between microleakage of conventionally restored class V cavities using acid etchant and the ones conditioned by erbium-doped yttrium aluminum garnet (Er:YAG) laser, and also to assess and compare the effectiveness of enamel surface treatments of occlusal pits and fissures by acid etching and conditioned by Er:YAG laser-etch. Materials and methods: Seventy-two extracted third molars were used in this study. The samples were divided into two major groups: class V cavities and pit and fissure sealants. Each subgroup was divided into conventional acid etching, Er:YAG laser conditioning and conventional acid etching, and combination with Er:YAG laser conditioning (n 12). The teeth were placed in 2% methylene blue dye solution, were sectioned, and were evaluated according to the dye penetration criteria. Two samples per subgroup were chosen for scanning electron microscopic (SEM) analysis. Results: There was a significant difference between occlusal and cervical margin groups. Laser conventional composite cementum group showed more microleakage values compared to other groups. There was no significant difference between occlusal margin groups. However, there was a significant difference between cervical margin groups in terms of microleakage. In sealant groups, there was a significant difference between laser and conventional with/without laser treatment groups in terms of microleakage. Conclusion: Based on the results reported in this study, it can be concluded that the application of the Er:YAG laser beneath the resin composite, the resin-modified glass ionomers (GIs), and the fissure sealant placement may be an alternative enamel and dentin etching method to acid etching.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
A comparative study of car ownership in Mashhad & Koln cities using linear regression model
Beta-tricalcium phosphate, white mineral trioxide aggregate, white Portland cement, ferric sulfate, and formocresol used as pulpotomy agents in primary pig teeth.
The purpose of this study was to evaluate and compare the effects of formocresol (FC), ferric sulfate (FS), white mineral trioxide aggregate (WMTA), white Portland cement (WPC), and beta-tricalcium phosphate (beta-TCP) on pulpotomized primary teeth of pigs.Comparative StudyJournal Articleinfo:eu-repo/semantics/publishe
The prevalence of traumatic dental injuries: a 24-month survey.
The aim of the present investigation was to assess the prevalence of dental traumatic injuries in children referred to Queen Fabiola Children's Hospital, Free University of Brussels, Belgium. This study was based on the clinical data of 457 traumatized teeth in 214 children. Most injuries involved 2 teeth (51%). Of these, maxillary central incisors were the most affected teeth (89%). The highest frequency of trauma occurred between 2 and 4 years of age. Falls were the most common cause of injury in both girls and boys. The most common type of injury in the primary and permanent teeth was subluxation. Gingival and mucosal laceration was the most common type of soft tissue lesion (61%). Only 42% of children came for dental treatment on the same day that they were injured.Journal Articleinfo:eu-repo/semantics/publishe