Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
1.
Cells ; 13(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38534357

RESUMO

The development of obesity is associated with substantial modulation of adipose tissue (AT) structure. The plasticity of the AT is reflected by its remarkable ability to expand or reduce in size throughout the adult lifespan, which is linked to the development of its vasculature. This increase in AT vasculature could be mediated by the differentiation of adipose tissue-derived stem cells (ASCs) into endothelial cells (ECs) and form new microvasculature. We have already shown that microRNA (miRNA)-145 regulates the differentiation of ASCs into EC-like (ECL) cells. Here, we investigated whether ASCs-differentiation into ECs is governed by a miRNAs signature that depends on fat depot location and /or the metabolic condition produced by obesity. Human ASCs, which were obtained from white AT by surgical procedures from lean and obese patients, were induced to differentiate into ECL cells. We have identified that miRNA-29b-3p in both subcutaneous (s)ASCs and visceral ASCs and miRNA-424-5p and miRNA-378a-3p in subcutaneous (s)ASCs are involved in differentiation into EC-like cells. These miRNAs modulate their pro-angiogenic effects on ASCs by targeting FGFR1, NRP2, MAPK1, and TGF-ß2, and the MAPK signaling pathway. We show for the first time that miRNA-29b-3p upregulation contributes to ASCs' differentiation into ECL cells by directly targeting TGFB2 in both sASCs and visceral ASCs. Moreover, our results reveal that, independent of sASCs' origin (obese/lean), the upregulation of miRNA-378a-3p and the downregulation of miRNA-424-5p inhibit MAPK1 and overexpress FGFR1 and NRP2, respectively. In summary, both the adipose depot location and obesity affect the differentiation of resident ASCs through the expression of specific miRNAs.


Assuntos
Células-Tronco Mesenquimais , MicroRNAs , Adulto , Humanos , MicroRNAs/genética , Células Endoteliais/metabolismo , Tecido Adiposo/metabolismo , Células-Tronco Mesenquimais/metabolismo , Obesidade/metabolismo
2.
Int J Mol Sci ; 24(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36614270

RESUMO

Obesity is associated with metabolic disorders such as insulin resistance and type 2 diabetes mellitus (T2DM), further increasing an already heightened cardiovascular risk. Here, amongst obese class III bariatric surgery patients, we have investigated the effect of T2DM in serum and in two, same patient, adipose tissue (AT) depots through proteomic profile expression analyses. Serum and AT samples from subcutaneous (SAT) and visceral (VAT) fat were collected during bariatric surgery. Bead-based targeted multiplex assay systems were used to simultaneously detect and quantify multiple targets in serum samples (targeted proteomics) and analyze changes in adipokine serum composition. AT samples were assessed through an untargeted proteomics approach. Through a systems biology analysis of the proteomic data, information on the affected biological pathways was acquired. In obese class III individuals, the presence of T2DM induced a significantly higher systemic release of ghrelin, GLP-1, glucagon, MMP3, BAFF, chitinase 3-like 1, TNF-R1 and TNF-R2, and a lower systemic release of IL-8. SAT and VAT proteomes belonging to the same patient showed significant differences in local protein content. While the proteins upregulated in VAT were indicative of metabolic dysregulation, SAT protein upregulation suggested adequate endocrine regulation. The presence of T2DM significantly affected VAT protein composition through the upregulation of dysregulating metabolic pathways, but SAT protein composition was not significantly modified. Our results show that T2DM induces metabolic dysregulation in obese individuals with changes in systemic marker levels and impairment of proteostasis in VAT but not in SAT.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/metabolismo , Gordura Subcutânea/metabolismo , Proteômica , Biologia de Sistemas , Obesidade/metabolismo , Tecido Adiposo/metabolismo , Gordura Intra-Abdominal/metabolismo
3.
Antiviral Res ; 207: 105416, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36113629

RESUMO

Cellular responses to stress generally lead to the activation of the endoplasmic reticulum-associated protein degradation (ERAD) pathway. Several lines of study support that ERAD may be playing a proviral role during flaviviral infection. A key host factor in ERAD is the valosin-containing protein (VCP), an ATPase which ushers ubiquitin-tagged proteins to degradation by the proteasome. VCP exhibits different proviral activities, such as engaging in the biogenesis of viral replication organelles and facilitating flavivirus genome uncoating after the viral particle entry. To investigate the possible antiviral value of drugs targeting VCP, we tested two inhibitors: eeyarestatin I (EEY) and xanthohumol (XAN). Both compounds were highly effective in suppressing Zika virus (ZIKV) and Usutu virus (USUV) replication during infection in cell culture. Further analysis revealed an unexpected virucidal activity for EEY, but not for XAN. Preincubation of ZIKV or USUV with EEY before inoculation to cells resulted in significant decreases in infectivity in a dose- and time-dependent manner. Viral genomes in samples previously treated with EEY were more sensitive to propidium monoazide, an intercalating agent, with 10- to 100-fold decreases observed in viral RNA levels, supporting that EEY affects viral particle integrity. Altogether, these results support that EEY is a strong virucide against two unrelated flaviviruses, encouraging further studies to investigate its potential use as a broad-acting drug or the development of improved derivatives in the treatment of flaviviral infection.


Assuntos
Infecções por Flavivirus , Flavivirus , Infecção por Zika virus , Zika virus , Adenosina Trifosfatases/metabolismo , Adenosina Trifosfatases/farmacologia , Adenosina Trifosfatases/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico , Flavivirus/genética , Humanos , Hidrazonas , Hidroxiureia/análogos & derivados , Substâncias Intercalantes/farmacologia , Substâncias Intercalantes/uso terapêutico , Complexo de Endopeptidases do Proteassoma/metabolismo , RNA Viral/genética , Ubiquitinas/metabolismo , Proteína com Valosina/metabolismo , Replicação Viral
4.
Nanomaterials (Basel) ; 12(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35957092

RESUMO

Cloth used for facemask material has been coated with silver nanoparticles using an aerosol method that passes pure uncoated nanoparticles through the cloth and deposits them throughout the volume. The particles have been characterized by electron microscopy and have a typical diameter of 4 nm with the atomic structure of pure metallic silver presented as an assortment of single crystals and polycrystals. The particles adhere well to the cloth fibers, and the coating consists of individual nanoparticles at low deposition times, evolving to fully agglomerated assemblies in heavy coatings. The cloth was exposed to Usutu virus and murine norovirus particles in suspension and allowed to dry, following which, the infectious virus particles were rescued by soaking the cloth in culture media. It was found that up to 98% of the virus particles were neutralized by this contact with the silver nanoparticles for optimum deposition conditions. The best performance was obtained with agglomerated films and with polycrystalline nanoparticles. The work indicates that silver nanoparticles embedded in masks can neutralize the majority of virus particles that enter the mask and thus increase the opacity of masks to infectious viruses by up to a factor of 50. In addition, the majority of the virus particles released from the mask after use are non-infectious.

5.
Cells ; 9(10)2020 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-33022994

RESUMO

BACKGROUND: The increase in the incidence of obesity and obesity-related cardiovascular risk factors (CVRFs) over the last decades has brought attention on adipose tissue (AT) pathobiology. The expansion of AT is associated with the development of new vasculature needed to perfuse the tissue; however, not all fat depots have the same ability to induce angiogenesis that requires recruitment of their own endothelial cells. In this study we have investigated the effect of different CVRFs, on the angiogenic capacity of the subcutaneous (SAT) and visceral (VAT) adipose tissue and on the function of their mesenchymal cell reservoir. METHODS: A transcriptomic approach was used to compare the different angiogenic and inflammatory profiles of the subcutaneous and visceral fat depots from individuals with obesity, as well as their resident stem cells (ASCs). Influence of other risk factors on fat composition was also measured. Finally, the microvesicles (MVs) released by ASCs were isolated and their regenerative potential analyzed by molecular and cellular methodologies. RESULTS: Obesity decreases the angiogenic capacity of AT. There are differences between SAT and VAT; from the 21 angiogenic-related genes analyzed, only three were decreased in SAT compared with those decreased in VAT. ASCs isolated from both fat depots showed significant differences; there was a significant up-regulation of the VEGF-pathway on visceral derived ASCs. ASCs release MVs that stimulate endothelial cell migration and angiogenic capacity. CONCLUSIONS: In patients with obesity, SAT expresses a greater number of angiogenic molecules than VAT, independent of the presence of other CVRFs.


Assuntos
Tecido Adiposo/fisiologia , Doenças Cardiovasculares/fisiopatologia , Células-Tronco/metabolismo , Transcriptoma/fisiologia , Adulto , Feminino , Humanos , Masculino , Fatores de Risco
6.
Dent Traumatol ; 30(5): 356-361, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24502222

RESUMO

BACKGROUND/AIM: The aim of this in vitro study was to investigate the impact fracture resistance of anterior teeth that had been fractured and restored with modified partial-coverage ceramics using the edge-up technique. MATERIAL AND METHODS: A total of 178 extracted human mandibular central and lateral incisors were included in this study. The incisors were randomly divided into two groups. Group 1 (n = 89) teeth were cleaved and restored with modified partial-coverage ceramics using the edge-up technique; Group 2 (n = 89) consisted of intact teeth that served as control. Impact strength was tested in a modified impact testing machine (pendulum type), and the severity of crown fracture after fracture resistance test was registered. RESULTS: Impact strength was insignificantly lower in restored teeth (median 5.39 and range 0.81-14.12 kJ m(-2) ) than in intact teeth (median 5.45 and range 0.31-16.47 kJ m(-2) ), although no statistically significant differences were observed. Regarding the severity of crown fracture, restored teeth showed a lower rate of severe fractures (20.22%) compared to intact teeth (25.84%), but no statistically significant differences were observed. CONCLUSIONS: Restoration of cleaved mandibular incisors with modified partial-coverage ceramics using the edge-up technique shows fracture resistance and severity of crown fracture following traumatism similar to intact teeth. In this way, this technique can be used successfully for the treatment of fractured anterior teeth.


Assuntos
Cerâmica , Restauração Dentária Permanente , Incisivo , Mandíbula , Humanos , Técnicas In Vitro
7.
Rev Esp Enferm Dig ; 103(4): 184-90, 2011 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-21526871

RESUMO

INTRODUCTION AND OBJECTIVE: pancreatic endocrine tumors (PET) are difficult to diagnose. Their accurate localization using imaging techniques is intended to provide a definite cure. The goal of this retrospective study was to review a PET series from a private institution. PATIENTS AND METHODS: the medical records of 19 patients with PETs were reviewed, including 4 cases of MEN-1, for a period of 17 years (1994-2010). A database was set up with ten parameters: age, sex, symptoms, imaging techniques, size and location in the pancreas, metastasis, surgery, complications, adjuvant therapies, definite diagnosis, and survival or death. RESULTS: a total of 19 cases were analyzed. Mean age at presentation was 51 years (range: 26-67 y) (14 males, 5 females), and tumor size was 5 to 80 mm (X: 20 mm). Metastatic disease was present in 37% (7/19). Most underwent the following imaging techniques: ultrasounds, computed tomography (CT) an magnetic resonance imaging (MRI). Fine needle aspiration punction (FNA) was performed for the primary tumor in 4 cases. Non-functioning: 7 cases (37%), insulinoma: 2 cases [1 with possible multiple endocrine neoplasia (MEN)], Zollinger-Ellison syndrome (ZES) from gastrinoma: 5 (3 with MEN-1), glucagonoma: 2 cases, 2 somatostatinomas; carcinoid: 1 case with carcinoide-like syndrome. Most patients were operated upon: 14/19 (73%). Four (4/14:28%) has postoperative complications following pancreatectomy: pancreatitis, pseudocyst, and abdominal collections. Some patients received chemotherapy (4), somatostatin (3) and interferon (2) before or after surgery. Median follow-up was 48 months. Actuarial survival during the study was 73.6% (14/19). CONCLUSIONS: age was similar to that described in the literature. Males were predominant. Most cases were non-functioning (37%). Most patients underwent surgery (73%) with little morbidity (28%) and an actuarial survival of 73.6% at the time of the study.


Assuntos
Apudoma/epidemiologia , Neoplasias Pancreáticas/epidemiologia , Adulto , Idoso , Apudoma/diagnóstico , Apudoma/patologia , Apudoma/cirurgia , Bases de Dados Factuais , Diagnóstico por Imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla Tipo 1/epidemiologia , Pancreatectomia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Prognóstico , Estudos Retrospectivos , Espanha/epidemiologia , Taxa de Sobrevida
8.
Rev. esp. enferm. dig ; 103(4): 184-190, abr. 2011. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-128990

RESUMO

Introducción y objetivo: los tumores endocrinos pancreáticos (TEP) son difíciles de diagnosticar. Su localización exacta mediante métodos de imagen tiene el propósito de lograr una curación definitiva. El objetivo de este trabajo retrospectivo fue revisar una serie institucional privada de TEP. Pacientes y métodos: se revisaron las historias clínicas de 19 pacientes con TEP, 4 casos con NEM-1, observados durante 17 años (1994-2010). Se creó una base de datos con diez parámetros: edad y sexo, síntomas, métodos diagnósticos de imagen, tamaño y situación en el páncreas, metástasis, cirugía, complicaciones, tratamientos complementarios, diagnóstico definitivo, supervivencia o éxitus. Resultados: en total se analizaron 19 casos. La edad media de presentación fue 51 años (intervalo: 26-67 años) (14 varones y 5 mujeres), con un tamaño del tumor de 5 a 80 mm (X: 20 mm). El 37% (7/19) tenían metástasis. En la mayoría se practicaron los siguientes métodos de imagen: ecografía, TAC y RM. La PAAF del tumor primitivo se practicó en 4 casos. No funcionantes: 7 casos (37%), insulinomas: 2 casos (1 con posible NEM), SZE por gastrinomas: 5 (3 con NEM-1), glucagonoma: 2 casos, 2 somatostatinomas, carcinoide: 1 caso con síndrome carcinoide-like. La mayoría de los enfermos fueron intervenidos quirúrgicamente 14/19 (73%). En cuatro (4/14: 28%) pacientes hubo complicaciones postoperatorias después de pancreatectomías: páncreas, seudoquiste y colecciones abdominales. Algunos casos fueron tratados con quimioterapia (4), somatostatina (3) e interferón (2) antes o después de la cirugía. La mediana de seguimiento fue de 48 meses. La supervivencia actuarial en el momento del estudio fue del 73,6% (14/19). Conclusiones: la edad fue similar a lo descrito en la literatura. El sexo predominante fue el masculino. La mayoría fueron no funcionantes (37%). La mayoría fueron intervenidos quirúrgicamente (73%), con escasa morbilidad (28%) y con una supervivencia actuarial en el momento de cerrar el estudio del 73,6%(AU)


Introduction and objective: pancreatic endocrine tumors (PET) are difficult to diagnose. Their accurate localization using imaging techniques is intended to provide a definite cure. The goal of this retrospective study was to review a PET series from a private institution. Patients and methods: the medical records of 19 patients with PETs were reviewed, including 4 cases of MEN-1, for a period of 17 years (1994-2010). A database was set up with ten parameters: age, sex, symptoms, imaging techniques, size and location in the pancreas, metastasis, surgery, complications, adjuvant therapies, definite diagnosis, and survival or death. Results: a total of 19 cases were analyzed. Mean age at presentation was 51 years (range: 26-67 y) (14 males, 5 females), and tumor size was 5 to 80 mm (X: 20 mm). Metastatic disease was present in 37% (7/19). Most underwent the following imaging techniques: ultrasounds, computed tomography (CT) and magnetic resonance imaging (MRI). Fine needle aspiration punction (FNA) was performed for the primary tumor in 4 cases. Nonfunctioning: 7 cases (37%), insulinoma: 2 cases [1 with possible multiple endocrine neoplasia (MEN)], Zollinger-Ellison syndrome (ZES) from gastrinoma: 5 (3 with MEN-1), glucagonoma: 2 cases, 2 somatostatinomas; carcinoid: 1 case with carcinoide-like syndrome. Most patients were operated upon: 14/19 (73%). Four (4/14: 28%) has postoperative complications following pancreatectomy: pancreatitis, pseudocyst, and abdominal collections. Some patients received chemotherapy (4), somatostatin (3) and interferon (2) before or after surgery. Median follow-up was 48 months. Actuarial survival during the study was 73.6% (14/19). Conclusions: age was similar to that described in the literature. Males were predominant. Most cases were non-functioning (37%). Most patients underwent surgery (73%) with little morbidity (28%) and an actuarial survival of 73.6% at the time of the study(AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Neoplasias das Glândulas Endócrinas/complicações , Neoplasias das Glândulas Endócrinas/diagnóstico , Insulinoma/complicações , Insulinoma/diagnóstico , Gastrinoma/complicações , Síndrome de Zollinger-Ellison/complicações , Somatostatina , Interferons , Angiografia , Neoplasias das Glândulas Endócrinas/fisiopatologia , Neoplasias das Glândulas Endócrinas , Estudos Retrospectivos , Insulinoma/fisiopatologia , Insulinoma , Vipoma/complicações
9.
Obes Surg ; 21(1): 36-41, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20396992

RESUMO

BACKGROUND AND AIMS: Laparoscopic Roux-en-Y gastric bypass (LRYGB) is the most frequent technique performed in bariatric surgery. Gastrojejunal anastomotic stricture is one of the most common postoperative complications. The aims of this study were to evaluate the efficacy and safety of endoscopic balloon dilation in the treatment of the gastrojejunal anastomotic strictures after LRYGB and to look for predicting factors that would indicate the need of repeated dilations. METHODS: We included all patients with morbid obesity who underwent a LRYGB at our institution between January 2002 and July 2007. All patients who developed symptoms compatible with stricture of the gastrojejunostomy were referred to upper gastrointestinal endoscopy and underwent endoscopic balloon dilation. RESULTS: One hundred and five out of the 1,330 patients (7.8%) developed an anastomotic stricture. The mean time to diagnosis was 3 months after the surgery. The mean diameter of the stricture was 5 mm. Sixty out of the 105 patients required only one dilation (57%), 29 required two dilations (27,6%), 13 required three dilations, and 3 patients underwent a fourth dilation. Clinical success was achieved in 100% of the cases, with an average of 1.6 dilations. The statistical analysis showed that only the time from surgery to stricture formation (p = 0.007) and the diameter achieved at the first dilation (p = 0.015) had statistical significance as predictors of the need of one or more dilations. CONCLUSIONS: Endoscopic balloon dilation is a safe and effective method. Most of the patients are successfully managed with one or two dilations. The longer time from surgery to the appearance of symptoms ant the largest diameter achieved at the first dilation are the only predicting factors of success with only one dilation.


Assuntos
Anastomose Cirúrgica/efeitos adversos , Cateterismo , Derivação Gástrica/efeitos adversos , Jejuno/cirurgia , Obesidade Mórbida/cirurgia , Estômago/cirurgia , Adolescente , Adulto , Idoso , Constrição Patológica/etiologia , Constrição Patológica/terapia , Feminino , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Falha de Tratamento , Resultado do Tratamento , Adulto Jovem
10.
Obes Surg ; 18(6): 623-30, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18392906

RESUMO

BACKGROUND: Anastomotic leaks after bariatric surgery carry high morbidity and mortality. We aimed to describe our experience of the diagnosis and management of gastrointestinal anastomotic leaks in patients undergoing laparoscopic gastric bypass in a single institution. METHODS: Of 1,200 patients who underwent laparoscopic Roux-en-Y gastric bypass with manual gastrojejunal anastomosis for morbid obesity from January 2002 to January 2007, we retrospectively analyzed 59 patients with anastomotic leak. The location of the leak, day of diagnosis, diagnostic methods, clinical manifestations, treatment modalities, associated complications, and length of hospital stay were analyzed. RESULTS: Leaks were located as follows: 67.8% in the gastrojejunostomy, 10.2% in the gastric pouch, 3.4% in the excluded stomach, 5.1% in the jejunojejunal anastomosis, 3.4% in the gastrojejunostomy plus pouch, 3.4% in the pouch plus excluded stomach, and 6.8% in undetermined sites. Routine upper gastrointestinal series revealed contrast extravasation in nine patients (15.3%). Leaks were asymptomatic at diagnosis in 29 patients (49.2%). Surgical reintervention was carried out in 23 patients, and conservative treatment was provided in the remaining 36. Transfer to the intensive care unit was required in 11 patients, with five deaths (0.4%). CONCLUSION: In our experience, most anastomotic leaks can be managed with conservative measures alone. In many patients, abdominal drains are effective in the management of leaks, obviating the need for reintervention. Nasoenteral nutrition was effective in the non-operative management of gastrojejunal leaks in patients without signs of systemic toxicity.


Assuntos
Derivação Gástrica/efeitos adversos , Laparoscopia/efeitos adversos , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/terapia , Reoperação
11.
Am J Dent ; 18(5): 331-4, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16335042

RESUMO

PURPOSE: To assess the shear bond strength obtained with a new self-etching adhesive material (Adper Prompt-L-Pop) compared with the total-etch technique and posterior application of an adhesive (Prime & Bond NT) in both primary and permanent teeth. METHODS: 28 human teeth were selected (14 primary and 14 permanent). The vestibular and lingual surfaces were prepared in dentin, followed by application of the adhesive materials (Adper Prompt-L-Pop and Prime & Bond NT), in accordance with the instructions of the manufacturer. Compomer and composite (Compoglass and TPH Spectrum) were used as filler materials. The samples were thermocycled (150 cycles), after which adhesion was assessed with an Autograph AGS machine. The type of fracture produced was evaluated using an Olympus SCZ-CTV microscope. The data were compared by triple-factor analysis of variance, statistically significant differences being considered for P< 0.01. RESULTS: The adhesion strength achieved with Prime & Bond NT involving both composite and compomer as restorative material was significantly greater than with Prompt-L-Pop. No differences were observed between the two dentitions.


Assuntos
Bis-Fenol A-Glicidil Metacrilato/química , Adesivos Dentinários/química , Organofosfatos/química , Ácidos Polimetacrílicos/química , Análise de Variância , Dentição Permanente , Humanos , Resistência ao Cisalhamento , Dente Decíduo/química
12.
Artigo em Inglês | MEDLINE | ID: mdl-12789148

RESUMO

Cohen syndrome is a hereditary disorder transmitted as an autosomal-recessive trait. Approximately 100 cases have been reported in the genetic and pediatric literature. Despite the fact that oral alterations are often observed in these cases, only 1 work has been published addressing this specific topic, and it tended to concentrate on periodontal abnormalities. The present study details 2 new patients, 2 brothers (8 and 11 years old), and mainly consists of an analysis of the dentomaxillary anomalies that until now have not been studied in depth. In this study, the mandible, characterized as hypoplastic in Cohen syndrome, appears to be in a normal position; what really exists is a maxillary hyperplasia of genetic origin. We also put forward an observation hitherto undescribed in the literature: dental agenesis.


Assuntos
Anormalidades Craniofaciais/genética , Maxila/anormalidades , Anormalidades Dentárias/genética , Cefalometria , Criança , Humanos , Hiperplasia , Incisivo/anormalidades , Masculino , Má Oclusão Classe II de Angle/genética , Micrognatismo/patologia , Prognatismo/patologia , Síndrome
13.
J Dent Child (Chic) ; 70(1): 24-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12762604

RESUMO

PURPOSE: An in vitro study was conducted to evaluate enamel marginal microleakage following acid etching of two fissure sealants of established clinical efficacy. The purpose of this study was to assess sealant leakage following etching in combination with the use of latest-generation adhesives. METHODS: Clinicians removed 22 human premolars without caries for orthodontic reasons, stored them in distilled water, and sealed the occlusal surface. They used sealants Concise (3M) and Dyract seal (Dentsply DeTrey). They randomly distributed the premolars into two groups (N = 11) according to sealant used. The materials were manipulated according to the instructions of the manufacturer, and no invasive enamel preparing technique was used (enameloplasty). Staining was carried out with 2% fuchsin. The results were evaluated by the Mann-Whitney nonparametric test for the comparison of independent data samples. RESULTS: Concise sealant was seen to produce significantly greater marginal leakage than Dyract seal (P=.02). CONCLUSIONS: The application of an adhesive layer beneath the sealant afforded less microleakage than when no adhesive was used. Nevertheless despite the possibility of combining adhesives and sealant resins, with good bonding between both components over the entire fissure interface, microleakage was still observed, regardless of the material used. This suggests that presently there is no material is able to secure total sealing of the space between the material used and the dental tissue.


Assuntos
Infiltração Dentária/classificação , Selantes de Fossas e Fissuras/química , Condicionamento Ácido do Dente , Bis-Fenol A-Glicidil Metacrilato/química , Compômeros/química , Colagem Dentária , Esmalte Dentário/ultraestrutura , Adesivos Dentinários/química , Humanos , Teste de Materiais , Corantes de Rosanilina , Estatísticas não Paramétricas
14.
Artigo em Es | IBECS | ID: ibc-23028

RESUMO

Las lesiones del ligamento periodontal son muy frecuentes tras golpes o caídas. Si el diente no es capaz de absorber toda la energía del choque, éste se desplaza, por lo que se lesiona el ligamento periodontal. En este artículo se analiza, desde el punto de vista histopatológico y clínico, la complicación periodontal más frecuente, la reabsorción radicular; para ello se ha llevado a cabo una búsqueda bibliográfica de los artículos y monografías relacionadas con el tema a través de la base de datos Pubmed, realizándose un medline con sus resúmenes correspondientes. Conclusión: hasta el momento no se conoce el mecanismo exacto por el que la raíz es resistente, en algunas situaciones clínicas, a la reabsorción radicular. (AU)


Assuntos
Humanos , Ligamento Periodontal/lesões , Reabsorção da Raiz/fisiopatologia , Avulsão Dentária/fisiopatologia
15.
Artigo em Es | IBECS | ID: ibc-23027

RESUMO

Las fracturas de la corona raíz suponen un reto para el tratamiento. Se puede utilizar, si la fractura abarca menos de un tercio de la longitud del diente, la tracción ortodóncica, gingivectomía, ostectomía y restauración. Pero si la fractura es muy subgingival, Kahnberg propuso una alternativa que, aunque en principio parece muy arriesgada, en los estudios longitudinales tiene un índice de complicaciones mínimo. Consiste en la extrusión quirúrgica y recolocación del diente. El objetivo de este trabajo es presentar un caso tratado con esta técnica y su evolución al cabo de cuatro años, observando que no existieron complicaciones de ningún tipo. (AU)


Assuntos
Adolescente , Masculino , Humanos , Coroa do Dente/lesões , Raiz Dentária/lesões , Fraturas dos Dentes/terapia , Técnicas de Movimentação Dentária , Reimplante Dentário , Seguimentos
16.
Artigo em Es | IBECS | ID: ibc-23026

RESUMO

Aunque la prevalencia de la avulsión dental es baja (del 1 al 16 por ciento de todos los traumatismos), el pronóstico a largo plazo es sombrío, ya que sólo del 4 al 50 por ciento de los dientes avulsionados sobreviven más de diez años. El objetivo de este artículo de revisión es servir de complemento a los recientemente publicados por la Asociación Internacional de Traumatología Dental (2001) y la Asociación Americana de Endodoncia (1994) en sus guías de tratamiento de la avulsión dental. Además, los autores revisan las diferentes posibilidades terapéuticas, según el período extraoral y el grado de desarrollo radicular, así como las novedades terapéuticas que están siendo investigadas. El método utilizado ha sido revisar los estudios publicados en la bibliografía médica a través del buscador Medline. Conclusiones: aunque se están utilizando diversos fármacos para evitar o disminuir la aparición de complicaciones, como la reabsorción radicular inflamatoria, se sigue insistiendo que el tiempo extraoral, el medio de conservación, el tipo y tiempo de ferulización, el estado de desarrollo radicular y el manejo endodóncico son los factores determinantes en el pronóstico a largo plazo del diente avulsionado. (AU)


Assuntos
Humanos , Avulsão Dentária/terapia , Reimplante Dentário , Prognóstico , Fatores de Tempo
17.
Artigo em Es | IBECS | ID: ibc-23025

RESUMO

Las lesiones del ligamento periodontal son los traumatismos que suelen ocurrir más frecuentemente, tanto en la dentición temporal como en la primera fase de la dentición mixta, ya que los espacios medulares son amplios y el ligamento periodontal es más elástico, no sujetando al diente de una manera estable. A pesar del avance en los conocimientos clínicos y terapéuticos en traumatología dental, el manejo clínico de las luxaciones dentales sigue siendo algo controvertido. El objetivo planteado en este trabajo de revisión es establecer los criterios diagnósticos, así como las diferentes medidas terapéuticas para el control y manejo de las luxaciones dentales, desde el punto de vista de la evidencia científica. El método ha consistido en analizar los estudios publicados en la bibliografía médica, utilizando los recursos habituales. Conclusión: para un tipo concreto de luxación, como es la intrusiva, en la actualidad no existe un protocolo definido para el tratamiento. (AU)


Assuntos
Humanos , Avulsão Dentária/terapia , Dentição Permanente , Avulsão Dentária
18.
Artigo em Es | IBECS | ID: ibc-23023

RESUMO

En el mundo occidental los traumatismos dentales están adquiriendo una relevancia importante dentro de la profesión dental. El objetivo del presente artículo ha sido realizar una revisión bibliográfica sobre los estudios de prevalencia y etiología de los traumatismos dentales, desde 1995 hasta la actualidad. Método: analizar los estudios publicados en la bibliografía médica, utilizando el buscador Medline. Resultados y conclusiones: se constata que la prevalencia es elevada, y entre las causas que los provocan, las actividades deportivas, el estado emocional y la violencia ocupan un papel preponderante (AU)


Assuntos
Feminino , Masculino , Humanos , Traumatismos Dentários/epidemiologia , Traumatismos Dentários/etiologia , Prevalência , Traumatismos em Atletas/complicações , Emoções , Violência , Fatores de Risco
19.
Artigo em Es | IBECS | ID: ibc-23024

RESUMO

La técnica de unión de fragmento en caso de una fractura de la corona es un procedimiento aceptado en la comunidad científica internacional. El primer autor que describió una forma de adhesión del fragmento fue Simonsen. Una modificación de dicha técnica fue propuesta por Andreasen y consistía en, previo grabado ácido de las superficies dentales expuestas, la unión por medio de un composite, y una vez pegado realizar un chaflán curvo alrededor de la línea de fractura, el cual se rellena también con material compuesto. En este artículo proponemos una alternativa a la técnica convencional, consistente en el vaciamiento de la dentina del fragmento fracturado, rellenándolo con composite para dentina (AU)


Assuntos
Humanos , Coroa do Dente/lesões , Traumatismos Dentários/terapia , Resinas Compostas , Colagem Dentária
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...