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1.
Mol Hum Reprod ; 30(5)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38718206

RESUMO

Paxillin is a ubiquitously expressed adaptor protein integral to focal adhesions, cell motility, and apoptosis. Paxillin has also recently been implicated as a mediator of nongenomic androgen receptor (AR) signaling in prostate cancer and other cells. We sought to investigate the relationship between paxillin and AR in granulosa cells (GCs), where androgen actions, apoptosis, and focal adhesions are of known importance, but where the role of paxillin is understudied. We recently showed that paxillin knockout in mouse GCs increases fertility in older mice. Here, we demonstrate that paxillin knockdown in human granulosa-derived KGN cells, as well as knockout in mouse primary GCs, results in reduced AR protein but not reduced mRNA expression. Further, we find that both AR protein and mRNA half-lives are reduced by approximately one-third in the absence of paxillin, but that cells adapt to chronic loss of paxillin by upregulating AR gene expression. Using co-immunofluorescence and proximity ligation assays, we show that paxillin and AR co-localize at the plasma membrane in GCs in a focal adhesion kinase-dependent way, and that disruption of focal adhesions leads to reduced AR protein level. Our findings suggest that paxillin recruits AR to the GC membrane, where it may be sequestered from proteasomal degradation and poised for nongenomic signaling, as reported in other tissues. To investigate the physiological significance of this in disorders of androgen excess, we tested the effect of GC-specific paxillin knockout in a mouse model of polycystic ovary syndrome (PCOS) induced by chronic postnatal dihydrotestosterone (DHT) exposure. While none of the control mice had estrous cycles, 33% of paxillin knockout mice were cycling, indicating that paxillin deletion may offer partial protection from the negative effects of androgen excess by reducing AR expression. Paxillin-knockout GCs from mice with DHT-induced PCOS also produced more estradiol than GCs from littermate controls. Thus, paxillin may be a novel target in the management of androgen-related disorders in women, such as PCOS.


Assuntos
Adesões Focais , Células da Granulosa , Camundongos Knockout , Paxilina , Receptores Androgênicos , Animais , Feminino , Humanos , Camundongos , Adesões Focais/metabolismo , Regulação da Expressão Gênica , Células da Granulosa/metabolismo , Células da Granulosa/efeitos dos fármacos , Paxilina/metabolismo , Paxilina/genética , Receptores Androgênicos/metabolismo , Receptores Androgênicos/genética , Transdução de Sinais
2.
Biol Sex Differ ; 13(1): 57, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36221127

RESUMO

BACKGROUND: The pituitary gland regulates essential physiological processes such as growth, pubertal onset, stress response, metabolism, reproduction, and lactation. While sex biases in these functions and hormone production have been described, the underlying identity, temporal deployment, and cell-type specificity of sex-biased pituitary gene regulatory networks are not fully understood. METHODS: To capture sex differences in pituitary gene regulation dynamics during postnatal development, we performed 3' untranslated region sequencing and small RNA sequencing to ascertain gene and microRNA expression, respectively, across five postnatal ages (postnatal days 12, 22, 27, 32, 37) that span the pubertal transition in female and male C57BL/6J mouse pituitaries (n = 5-6 biological replicates for each sex at each age). RESULTS: We observed over 900 instances of sex-biased gene expression and 17 sex-biased microRNAs, with the majority of sex differences occurring with puberty. Using miRNA-gene target interaction databases, we identified 18 sex-biased genes that were putative targets of 5 sex-biased microRNAs. In addition, by combining our bulk RNA-seq with publicly available male and female mouse pituitary single-nuclei RNA-seq data, we obtained evidence that cell-type proportion sex differences exist prior to puberty and persist post-puberty for three major hormone-producing cell types: somatotropes, lactotropes, and gonadotropes. Finally, we identified sex-biased genes in these three pituitary cell types after accounting for cell-type proportion differences between sexes. CONCLUSION: Our study reveals the identity and postnatal developmental trajectory of sex-biased gene expression in the mouse pituitary. This work also highlights the importance of considering sex biases in cell-type composition when understanding sex differences in the processes regulated by the pituitary gland.


Assuntos
MicroRNAs , Hipófise , Regiões 3' não Traduzidas , Animais , Feminino , Expressão Gênica , Hormônios/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Hipófise/metabolismo
3.
Transl Psychiatry ; 11(1): 149, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33654064

RESUMO

Maternal environmental exposures, such as high-fat diets, diabetes and obesity, can induce long-term effects in offspring. These effects include increased risk of neurodevelopmental disorders (NDDs) including autism spectrum disorder (ASD), depression and anxiety. The mechanisms underlying these late-life neurologic effects are unknown. In this article, we measured changes in the offspring brain and determined which brain regions are sensitive to maternal metabolic milieu and therefore may mediate NDD risk. We showed that mice exposed to a maternal high-fat diet display extensive brain changes in adulthood despite being switched to a low-fat diet at weaning. Brain regions impacted by early-life diet include the extended amygdalar system, which plays an important role in reward-seeking behaviour. Genes preferentially expressed in these regions have functions related to feeding behaviour, while also being implicated in human NDDs, such as autism. Our data demonstrated that exposure to maternal high-fat diet in early-life leads to brain alterations that persist into adulthood, even after dietary modifications.


Assuntos
Transtorno do Espectro Autista , Efeitos Tardios da Exposição Pré-Natal , Adulto , Filhos Adultos , Animais , Transtorno do Espectro Autista/etiologia , Encéfalo , Dieta Hiperlipídica/efeitos adversos , Feminino , Humanos , Camundongos , Gravidez
4.
J Biol Chem ; 293(22): 8449-8461, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29610276

RESUMO

The CCCTC-binding factor (CTCF) is a versatile transcriptional regulator required for embryogenesis, but its function in vascular development or in diseases with a vascular component is poorly understood. Here, we found that endothelial Ctcf is essential for mouse vascular development and limits accumulation of reactive oxygen species (ROS). Conditional knockout of Ctcf in endothelial progenitors and their descendants affected embryonic growth, and caused lethality at embryonic day 10.5 because of defective yolk sac and placental vascular development. Analysis of global gene expression revealed Frataxin (Fxn), the gene mutated in Friedreich's ataxia (FRDA), as the most strongly down-regulated gene in Ctcf-deficient placental endothelial cells. Moreover, in vitro reporter assays showed that Ctcf activates the Fxn promoter in endothelial cells. ROS are known to accumulate in the endothelium of FRDA patients. Importantly, Ctcf deficiency induced ROS-mediated DNA damage in endothelial cells in vitro, and in placental endothelium in vivo Taken together, our findings indicate that Ctcf promotes vascular development and limits oxidative stress in endothelial cells. These results reveal a function for Ctcf in vascular development, and suggest a potential mechanism for endothelial dysfunction in FRDA.


Assuntos
Fator de Ligação a CCCTC/fisiologia , Embrião de Mamíferos/patologia , Endotélio Vascular/patologia , Ataxia de Friedreich/patologia , Regulação da Expressão Gênica , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Animais , Células Cultivadas , Embrião de Mamíferos/metabolismo , Endotélio Vascular/metabolismo , Feminino , Ataxia de Friedreich/genética , Ataxia de Friedreich/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Proteínas de Ligação ao Ferro/genética , Proteínas de Ligação ao Ferro/metabolismo , Masculino , Camundongos , Camundongos Knockout , Frataxina
5.
Methods Mol Biol ; 1752: 11-16, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29564758

RESUMO

Whole mount immunofluorescence is a valuable technique that can be used to visualize vascular networks in early developing embryonic tissues. This technique involves the permeabilization of fixed mouse embryos and yolk sacs, and primary antibody tagging of the endothelial cell marker platelet endothelial cell adhesion molecule 1 (Pecam-1). A secondary antibody tagged with a fluorophore targets the primary antibody, fluorescently labeling endothelial cells and revealing vascular networks.


Assuntos
Embrião de Mamíferos/irrigação sanguínea , Saco Vitelino/irrigação sanguínea , Animais , Anticorpos/metabolismo , Células Endoteliais/metabolismo , Feminino , Imunofluorescência , Camundongos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Gravidez
6.
J Neuromuscul Dis ; 4(4): 293-306, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29125504

RESUMO

BACKGROUND: Recent short-term clinical trials in patients with Duchenne Muscular Dystrophy (DMD) have indicated greater disease variability in terms of progression than expected. In addition, as average life-expectancy increases, reliable data is required on clinical progression in the older DMD population. OBJECTIVE: To determine the effects of corticosteroids on major clinical outcomes of DMD in a large multinational cohort of genetically confirmed DMD patients. METHODS: In this cross-sectional study we analysed clinical data from 5345 genetically confirmed DMD patients from 31 countries held within the TREAT-NMD global DMD database. For analysis patients were categorised by corticosteroid background and further stratified by age. RESULTS: Loss of ambulation in non-steroid treated patients was 10 years and in corticosteroid treated patients 13 years old (p = 0.0001). Corticosteroid treated patients were less likely to need scoliosis surgery (p < 0.001) or ventilatory support (p < 0.001) and there was a mild cardioprotective effect of corticosteroids in the patient population aged 20 years and older (p = 0.0035). Patients with a single deletion of exon 45 showed an increased survival in contrast to other single exon deletions. CONCLUSIONS: This study provides data on clinical outcomes of DMD across many healthcare settings and including a sizeable cohort of older patients. Our data confirm the benefits of corticosteroid treatment on ambulation, need for scoliosis surgery, ventilation and, to a lesser extent, cardiomyopathy. This study underlines the importance of data collection via patient registries and the critical role of multi-centre collaboration in the rare disease field.


Assuntos
Distrofia Muscular de Duchenne/epidemiologia , Distrofia Muscular de Duchenne/terapia , Adolescente , Corticosteroides/uso terapêutico , Adulto , Criança , Pré-Escolar , Estudos Transversais , Bases de Dados como Assunto , Humanos , Lactente , Recém-Nascido , Masculino , Distrofia Muscular de Duchenne/genética , Resultado do Tratamento , Adulto Jovem
7.
PLoS Genet ; 13(8): e1006985, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28846746

RESUMO

Cardiac progenitors are specified early in development and progressively differentiate and mature into fully functional cardiomyocytes. This process is controlled by an extensively studied transcriptional program. However, the regulatory events coordinating the progression of such program from development to maturation are largely unknown. Here, we show that the genome organizer CTCF is essential for cardiogenesis and that it mediates genomic interactions to coordinate cardiomyocyte differentiation and maturation in the developing heart. Inactivation of Ctcf in cardiac progenitor cells and their derivatives in vivo during development caused severe cardiac defects and death at embryonic day 12.5. Genome wide expression analysis in Ctcf mutant hearts revealed that genes controlling mitochondrial function and protein production, required for cardiomyocyte maturation, were upregulated. However, mitochondria from mutant cardiomyocytes do not mature properly. In contrast, multiple development regulatory genes near predicted heart enhancers, including genes in the IrxA cluster, were downregulated in Ctcf mutants, suggesting that CTCF promotes cardiomyocyte differentiation by facilitating enhancer-promoter interactions. Accordingly, loss of CTCF disrupts gene expression and chromatin interactions as shown by chromatin conformation capture followed by deep sequencing. Furthermore, CRISPR-mediated deletion of an intergenic CTCF site within the IrxA cluster alters gene expression in the developing heart. Thus, CTCF mediates local regulatory interactions to coordinate transcriptional programs controlling transitions in morphology and function during heart development.


Assuntos
Cromatina/genética , Desenvolvimento Embrionário/genética , Ventrículos do Coração/crescimento & desenvolvimento , Coração/crescimento & desenvolvimento , Proteínas Repressoras/genética , Animais , Fator de Ligação a CCCTC , Diferenciação Celular/genética , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica no Desenvolvimento , Coração/embriologia , Ventrículos do Coração/embriologia , Camundongos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Organogênese/genética , Regiões Promotoras Genéticas , Ligação Proteica , Ativação Transcricional/genética
8.
Development ; 144(11): 1976-1987, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28455378

RESUMO

Defective fetoplacental vascular maturation causes intrauterine growth restriction (IUGR). A transcriptional switch initiates placental maturation, during which blood vessels elongate. However, the cellular mechanisms and regulatory pathways involved are unknown. We show that the histone methyltransferase G9a, also known as Ehmt2, activates the Notch pathway to promote placental vascular maturation. Placental vasculature from embryos with G9a-deficient endothelial progenitor cells failed to expand owing to decreased endothelial cell proliferation and increased trophoblast proliferation. Moreover, G9a deficiency altered the transcriptional switch initiating placental maturation and caused downregulation of Notch pathway effectors including Rbpj Importantly, Notch pathway activation in G9a-deficient endothelial progenitors extended embryonic life and rescued placental vascular expansion. Thus, G9a activates the Notch pathway to balance endothelial cell and trophoblast proliferation and coordinates the transcriptional switch controlling placental vascular maturation. Accordingly, G9A and RBPJ were downregulated in human placentae from IUGR-affected pregnancies, suggesting that G9a is an important regulator in placental diseases caused by defective vascular maturation.


Assuntos
Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Placenta/irrigação sanguínea , Receptores Notch/metabolismo , Transdução de Sinais , Animais , Movimento Celular/genética , Proliferação de Células , Regulação para Baixo/genética , Embrião de Mamíferos/metabolismo , Embrião de Mamíferos/ultraestrutura , Desenvolvimento Embrionário/genética , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Feminino , Retardo do Crescimento Fetal/genética , Regulação da Expressão Gênica no Desenvolvimento , Antígenos de Histocompatibilidade/genética , Histona-Lisina N-Metiltransferase/genética , Humanos , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/genética , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/metabolismo , Camundongos , Organogênese/genética , Placenta/citologia , Placenta/ultraestrutura , Gravidez , Transdução de Sinais/genética , Células-Tronco/citologia , Células-Tronco/metabolismo , Transcrição Gênica , Trofoblastos/citologia , Trofoblastos/metabolismo
9.
Neuromuscul Disord ; 26(3): 211-20, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26826887

RESUMO

This study aims to investigate the clinimetric properties of ACTIVLIM, a measure of activity limitations, when it is used in daily practice in a large nationwide representative cohort of patients with neuromuscular diseases. A cohort of 2986 patients was assessed at least once over 2 years in 6 national neuromuscular diseases reference centers. Successive Rasch analyses were conducted in order to investigate the scale validity, reliability, consistency across demographic and clinical sub-groups and its sensitivity to change. ACTIVLIM confirmed excellent fit to a unidimensional scale, with stable but 3-times more accurate item calibrations compared to the original publication. It showed a good reliability (R = 0.95), an appropriate targeting for 87% of the sample and an excellent invariance across age, gender, language and time. Despite some variations in the item difficulty hierarchy across diagnoses, ACTIVLIM exhibited a good capability to quantify small but significant changes in activity for various diagnostic groups. Overall, ACTIVLIM demonstrated very good clinimetric properties, allowing accurate quantitative measurement of activity limitations in both children and adults with a variety of neuromuscular diseases.


Assuntos
Atividades Cotidianas , Avaliação da Deficiência , Doenças Neuromusculares/diagnóstico , Índice de Gravidade de Doença , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes , Adulto Jovem
10.
Hum Mutat ; 36(4): 395-402, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25604253

RESUMO

Analyzing the type and frequency of patient-specific mutations that give rise to Duchenne muscular dystrophy (DMD) is an invaluable tool for diagnostics, basic scientific research, trial planning, and improved clinical care. Locus-specific databases allow for the collection, organization, storage, and analysis of genetic variants of disease. Here, we describe the development and analysis of the TREAT-NMD DMD Global database (http://umd.be/TREAT_DMD/). We analyzed genetic data for 7,149 DMD mutations held within the database. A total of 5,682 large mutations were observed (80% of total mutations), of which 4,894 (86%) were deletions (1 exon or larger) and 784 (14%) were duplications (1 exon or larger). There were 1,445 small mutations (smaller than 1 exon, 20% of all mutations), of which 358 (25%) were small deletions and 132 (9%) small insertions and 199 (14%) affected the splice sites. Point mutations totalled 756 (52% of small mutations) with 726 (50%) nonsense mutations and 30 (2%) missense mutations. Finally, 22 (0.3%) mid-intronic mutations were observed. In addition, mutations were identified within the database that would potentially benefit from novel genetic therapies for DMD including stop codon read-through therapies (10% of total mutations) and exon skipping therapy (80% of deletions and 55% of total mutations).


Assuntos
Bases de Dados Genéticas , Distrofina/genética , Distrofia Muscular de Duchenne/genética , Mutação , Humanos , Sistema de Registros
11.
Acta Neurol Belg ; 115(2): 97-104, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24957677

RESUMO

The Belgian Neuromuscular Disease Registry, commissioned in 2008, aims to collect data to improve knowledge on neuromuscular diseases and enhance quality health services for neuromuscular disease patients. This paper presents a clear outline of the strategy to launch a global national registry. All patients diagnosed with one of the predefined 62 neuromuscular disease groups and living in Belgium may be included in the yearly updated Registry. Basic core data is harvested through a newly designed web application by the six accredited neuromuscular reference centres. In 2010, 3,424 patients with a neuromuscular disorder were registered. The most prevalent disease group in the Registry is Hereditary Motor and Sensory Neuropathy, as similarly stated by other studies, albeit the prevalence in Belgium is five times lower: 6.5 per 100,000 in the north of Belgium, versus 17.0-41.0 per 100,000 in other areas of Europe. Very few patients were captured in the south of the country. With the aim to collect valuable epidemiological data, the registry targets to gather high quality data, that the sample to be representative of the population and that it be complete. The past 5 years of building the registry have improved its quality, albeit the consistent gap in data from the south of the country prevails, influencing the estimated prevalence of these diseases. To this day, the true burden of neuromuscular diseases in Belgium is not known but actions have been undertaken to address these issues.


Assuntos
Doenças Neuromusculares/diagnóstico , Doenças Neuromusculares/epidemiologia , Doenças Raras/epidemiologia , Sistema de Registros , Adulto , Bélgica/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Neuromusculares/classificação , Sistemas On-Line/estatística & dados numéricos , Prevalência , Estudos Retrospectivos
12.
Nat Commun ; 5: 4533, 2014 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-25208486

RESUMO

Human dilated cardiomyopathy (DCM) manifests as a profound reduction in biventricular cardiac function that typically progresses to death or cardiac transplantation. There is no effective mechanism-based therapy currently available for DCM, in part because the transduction of mechanical load into dynamic changes in cardiac contractility (termed mechanotransduction) remains an incompletely understood process during both normal cardiac function and in disease states. Here we show that the mechanoreceptor protein integrin-linked kinase (ILK) mediates cardiomyocyte force transduction through regulation of the key calcium regulatory protein sarcoplasmic/endoplasmic reticulum Ca(2+)ATPase isoform 2a (SERCA-2a) and phosphorylation of phospholamban (PLN) in the human heart. A non-oncogenic ILK mutation with a synthetic point mutation in the pleckstrin homology-like domain (ILK(R211A)) is shown to enhance global cardiac function through SERCA-2a/PLN. Thus, ILK serves to link mechanoreception to the dynamic modulation of cardiac contractility through a previously undiscovered interaction with the functional SERCA-2a/PLN module that can be exploited to rescue impaired mechanotransduction in DCM.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Mecanotransdução Celular/genética , Contração Miocárdica/genética , Miócitos Cardíacos/metabolismo , Proteínas Serina-Treonina Quinases/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Animais , Humanos , Células-Tronco Pluripotentes Induzidas , Mecanotransdução Celular/fisiologia , Camundongos , Camundongos Knockout , Contração Miocárdica/fisiologia , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Retículo Sarcoplasmático/metabolismo
13.
Hum Mutat ; 34(11): 1449-57, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23913485

RESUMO

Duchenne muscular dystrophy (DMD) is an X-linked genetic disease, caused by the absence of the dystrophin protein. Although many novel therapies are under development for DMD, there is currently no cure and affected individuals are often confined to a wheelchair by their teens and die in their twenties/thirties. DMD is a rare disease (prevalence <5/10,000). Even the largest countries do not have enough affected patients to rigorously assess novel therapies, unravel genetic complexities, and determine patient outcomes. TREAT-NMD is a worldwide network for neuromuscular diseases that provides an infrastructure to support the delivery of promising new therapies for patients. The harmonized implementation of national and ultimately global patient registries has been central to the success of TREAT-NMD. For the DMD registries within TREAT-NMD, individual countries have chosen to collect patient information in the form of standardized patient registries to increase the overall patient population on which clinical outcomes and new technologies can be assessed. The registries comprise more than 13,500 patients from 31 different countries. Here, we describe how the TREAT-NMD national patient registries for DMD were established. We look at their continued growth and assess how successful they have been at fostering collaboration between academia, patient organizations, and industry.


Assuntos
Bases de Dados Factuais , Distrofia Muscular de Duchenne , Sistema de Registros , Bases de Dados Factuais/economia , Geografia Médica , Saúde Global , Humanos , Distrofia Muscular de Duchenne/economia , Distrofia Muscular de Duchenne/epidemiologia
14.
J Clin Diagn Res ; 7(11): 2637-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24392427

RESUMO

The variability of root canal system morphology of multirooted teeth represents a continuous challenge to endodontic diagnosis and therapeutics. This report extends the range of known possible anatomical variations to include teeth with lesser number of root and root canals. Variations of root canal systems need not always be in the form of extra canals. Clinicians should be aware that there is a possibility of existence of fewer number of roots and root canals than the normal root canal anatomy. Thus the aim of this article is to present three cases of endodontically managed mandibular second molars with a single root and root canal.

15.
Indian J Dent Res ; 23(4): 484-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23257482

RESUMO

AIM: The purpose of the study is to compare the regional micro-push-out bond strength of custom-made resin post and a prefabricated resin post luted using self-etch adhesive and/or etch and rinse adhesive system at various regions. MATERIALS AND METHODS: Forty freshly extracted human maxillary central incisors were selected for this study; 1.5-2-mm coronal to the cemento-enamel junction was removed with a diamond disk using a slow speed handpiece under cooling water. Working lengths were established, root canals were sequentially enlarged upto the apex until ISO size 50-K-file and obturated using gutta-percha and AH plus sealer by cold lateral compaction. Post spaces were prepared to a depth of 10 mm using paeso-reamer upto size #3. After preparation, each specimen was embedded in chemically cured acrylic resin. The roots were randomly assigned to four groups: Group I: Custom-made resin post+Self-etch adhesive, Group II: Glass FRC post+Self-etch adhesive, Group III: Custom-made resin post+Etch and Rinse adhesive, Group IV: Glass FRC post+Etch and Rinse adhesive. Fabrication of custom-made resin post was done. All the posts were cemented using a dual cure resin luting cement. Each root was sectioned perpendicular to the long axis using a microtome and subjected to micro-push-out bond strength. RESULTS: The micro-push-out bond strength in the coronal region, in Group I 13.5 ± 1.66 MPa, Group II 12.08 ± 0.8 MPa, Group III 11.15 ± 1.06 MPa, Group IV 11.81 ± 1.11 MPa. In the middle third region: Group I 11.43 ± 0.740 MPa, Group II 10.584 ± 0.504 MPa, Group III 10.0582 ± 0.830 MPa, Group IV 10.35 ± 0772 MPa. In the apical third: Group I 10.38 ± 0.878 MPa, Group II 9.59 ± 1.06 MPa, Group III 9.34 ± 0.73o MPa, Group IV 8.77 ± 1.02 MPa. CONCLUSION: Within the limitations of the study, amongst all the four groups tested, custom-made resin post luted with self-etch system (CMPR-SE) showed higher micro-push-out bond strength values in all regions when compared to the other groups.


Assuntos
Resinas Compostas/química , Colagem Dentária , Materiais Dentários/química , Planejamento de Prótese Dentária , Técnica para Retentor Intrarradicular/instrumentação , Condicionamento Ácido do Dente/métodos , Bis-Fenol A-Glicidil Metacrilato/química , Cimentação/métodos , Cavidade Pulpar/ultraestrutura , Dentina/ultraestrutura , Adesivos Dentinários/química , Vidro/química , Humanos , Teste de Materiais , Ácidos Fosfóricos/química , Cimentos de Resina/química , Obturação do Canal Radicular/métodos , Preparo de Canal Radicular/instrumentação , Preparo de Canal Radicular/métodos , Autocura de Resinas Dentárias , Estresse Mecânico , Ápice Dentário/ultraestrutura
16.
Artigo em Inglês | MEDLINE | ID: mdl-21444221

RESUMO

The aim of this article was to present an endodontically managed maxillary first molar with unusual C-shaped palatal root morphology confirmed by cone-beam computerized tomography (CBCT) images. CBCT axial images showed the presence of C-shaped palatal root canal anatomy with a palatal root bifurcation at the apical third. The evaluation of CBCT images can result in better understanding of root canal anatomy, which enables the clinician to investigate the root canal system and to clean, shape, and obturate it more effectively.


Assuntos
Cavidade Pulpar/anatomia & histologia , Dente Molar/anatomia & histologia , Adulto , Tomografia Computadorizada de Feixe Cônico , Cavidade Pulpar/diagnóstico por imagem , Cavidade Pulpar/patologia , Humanos , Masculino , Maxila , Dente Molar/diagnóstico por imagem , Dente Molar/patologia , Odontometria/métodos , Periodontite Periapical/diagnóstico por imagem , Periodontite Periapical/terapia , Pulpite/diagnóstico por imagem , Pulpite/terapia , Tratamento do Canal Radicular
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