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1.
Chinese Journal of Stomatology ; (12): 17-24, 2023.
Artículo en Chino | WPRIM | ID: wpr-970750

RESUMEN

The classification as well as the clinical manifestations of hereditary malformations of dentin are of great concern and have been deeply elucidated. The understanding of its genetic basis also increases progressively. Dentin sialophosphoprotein (DSPP) is the pathogenic gene of dentinogenesis imperfecta type Ⅱ, dentinogenesis imperfecta type Ⅲ and dentin dysplasia type Ⅱ. In this article, the classification of DSPP mutations as well as the resultant dysfunction of the mutant DSPP are summarized respectively and the corresponding clinical manifestations are analyzed. This work will provide a reference for the diagnosis and treatment of hereditary malformations of dentin.


Asunto(s)
Humanos , Dentinogénesis Imperfecta/patología , Mutación , Proteínas de la Matriz Extracelular/genética , Fosfoproteínas/genética , Sialoglicoproteínas/genética , Dentina/patología
2.
Int. j. morphol ; 39(3): 802-808, jun. 2021. tab
Artículo en Inglés | LILACS | ID: biblio-1385386

RESUMEN

SUMMARY: Dental caries corresponds to an ecological and non-contagious, dynamic and chronic disease of multifactorial origin; currently there is evidence of how genetic factors could be included as predisposing agents to suffer it, however this evidence is diverse and incipient. a cross-sectional study was p erformed to investigate the possible associations of DSPP (rs36094464), RUNX2 (rs566712) and KLK4 (rs198968) polymorphisms in early childhood caries. Saliva samples of children (2-11years old) were collected and genotyped for DSPP (rs36094464), RUNX2 (rs566712) and KLK4 (rs198968) polymorphisms. Through the ceft index their caries history was determined and the gene variants were students through molecular biology techniques. polymorphisms of the DSSP (rs36094464) and RUNX2 (rs566712) are associated and contribute to the susceptibility of dental caries disease in early childhood, as they are related to their history of caries. KLK4 (rs198968) polymorphisms are not associated. In conclusions, the studied polymorphisms on DSSP and RUNX2 genes are associated with changes in the tooth microarchitecture, favoring the appearance of microlesions that would contribute to dental caries disease susceptibility in early childhood. Also, no association was found for the studied polymorphism of the KLK4 gene with dental caries disease susceptibility.


RESUMEN: La caries dental corresponde a una enfermedad crónica, no contagiosa, dinámica y de origen multifactorial. Actualmente existe evidencia de cómo los factores genéticos podrían incluirse como agentes predisponentes, sin embargo, esta evidencia es diversa e incipiente. Se realizó un estudio transversal para investigar las posibles asociaciones entre los polimorfismos DSPP (rs36094464), RUNX2 (rs566712) y KLK4 (rs198968) y la caries en la infancia. Se colectaron muestras de saliva de niños (de 2 a 11 años de edad) y se genotipificaron para los polimorfismos DSPP (rs36094464), RUNX2 (rs566712) y KLK4 (rs198968). Mediante el índice ceft se determinó su historial de caries y se estudiaron las variantes genéticas mediante técnicas de biología molecular. Los datos obtenidos indican que los polimorfismos del DSSP (rs36094464) y RUNX2 (rs566712) están asociados y contribuyen a la susceptibilidad de la enfermedad de caries dental en la infancia, ya que están - además - relacionados con el historial de caries. En conclusión, los polimorfismos estudiados en los genes DSSP y RUNX2 se asocian a la aparición de microlesiones que contribuirían a la susceptibilidad a la enfermedad de caries dental en la infancia. Creemos que este estudio es importante para la odontopediatría porque destaca el papel de DSSP (rs36094464) y RUNX2 (rs566712) y la susceptibilidad a la caries dental durante la infancia, además resalta la utilidad de la evaluación genética para la predicción y prevención de la caries dental y porque aporta evidencia que indica que los factores genéticos están implicados en la etiología de la caries.


Asunto(s)
Humanos , Masculino , Femenino , Preescolar , Niño , Caries Dental/genética , Caries Dental/epidemiología , Fosfoproteínas/genética , Polimorfismo Genético , Saliva/química , Sialoglicoproteínas/genética , Calicreínas/genética , Estudios Transversales , Susceptibilidad a Caries Dentarias/genética , Dentina , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Genotipo , Biología Molecular
3.
J. appl. oral sci ; 28: e20190023, 2020. graf
Artículo en Inglés | LILACS | ID: biblio-1056577

RESUMEN

Abstract When exposure of the pulp to external environment occurs, reparative dentinogenesis can be induced by direct pulp capping to maintain pulp tissue vitality and function. These clinical situations require the use of materials that induce dentin repair and, subsequently, formation of a mineralized tissue. Objective: This work aims to assess the effect of tricalcium silicate cements and mineral trioxide aggregate cements, including repairing dentin formation and inflammatory reactions over time after pulp exposure in Wistar rats. Methodology: These two biomaterials were compared with positive control groups (open cavity with pulp tissue exposure) and negative control groups (no intervention). The evaluations were performed in three stages; three, seven and twenty-one days, and consisted of an imaging (nuclear medicine) and histological evaluation (H&E staining, immunohistochemistry and Alizarin Red S). Results: The therapeutic effect of these biomaterials was confirmed. Nuclear medicine evaluation demonstrated that the uptake of 99mTc-Hydroxymethylene diphosphonate (HMDP) showed no significant differences between the different experimental groups and the control, revealing the non-occurrence of differences in the phosphocalcium metabolism. The histological study demonstrated that in mineral trioxide aggregate therapies, the presence of moderate inflammatory infiltration was found after three days, decreasing during follow-ups. The formation of mineralized tissue was only verified at 21 days of follow-up. The tricalcium silicate therapies demonstrated the presence of a slight inflammatory infiltration on the third day, increasing throughout the follow-up. The formation of mineralized tissue was observed in the seventh follow-up day, increasing over time. Conclusions: The mineral trioxide aggregate (WhiteProRoot®MTA) and tricalcium silicate (Biodentine™) present slight and reversible inflammatory signs in the pulp tissue, with the formation of mineralized tissue. However, the exacerbated induction of mineralized tissue formation with the tricalcium silicate biomaterial may lead to the formation of pulp calcifications


Asunto(s)
Animales , Masculino , Óxidos/farmacología , Materiales Biocompatibles/farmacología , Silicatos/farmacología , Compuestos de Calcio/farmacología , Compuestos de Aluminio/farmacología , Pulpa Dental/efectos de los fármacos , Dentina/efectos de los fármacos , Dentinogénesis/efectos de los fármacos , Fosfoproteínas/análisis , Pulpitis/patología , Pulpitis/tratamiento farmacológico , Sialoglicoproteínas/análisis , Factores de Tiempo , Inmunohistoquímica , Distribución Aleatoria , Reproducibilidad de los Resultados , Proteínas de la Matriz Extracelular/análisis , Exposición de la Pulpa Dental/patología , Exposición de la Pulpa Dental/tratamiento farmacológico , Ratas Wistar , Pulpa Dental/patología , Recubrimiento de la Pulpa Dental/métodos , Combinación de Medicamentos , Imagen Molecular/métodos , Materiales de Recubrimiento Pulpar y Pulpectomía/farmacología , Odontoblastos/efectos de los fármacos
4.
West China Journal of Stomatology ; (6): 248-252, 2019.
Artículo en Chino | WPRIM | ID: wpr-772667

RESUMEN

OBJECTIVE@#To verify the effect of the mutant gene vps4b on the expression of tooth development-related proteins, dentin sialophosphoprotein (DSPP) and collagenⅠ (COL-Ⅰ).@*METHODS@#Paraffin tissue sections of the first molar tooth germ were obtained from the heads of fetal mice at the embryonic stages of 13.5, 14.5, and 16.5 days and from the mandibles of larvae aged 2.5 and 7 days after birth. The immunohistochemical method was used to detect the expression and location of DSPP and COL-Ⅰ in wild-type mouse and vps4b knockout mouse.@*RESULTS@#DSPP and COL-Ⅰ were not found in the bud and cap stages of wild-type mouse molar germ. In the bell stage, DSPP was positively expressed in the inner enamel epithelium and dental papilla, whereas COL-Ⅰ was strongly expressed in the dental papilla and dental follicle. During the secretory and mineralized periods, DSPP and COL-Ⅰ were intensely observed in ameloblasts, odontoblasts, and dental follicles, but COL-Ⅰ was also expressed in the dental papilla. After vps4b gene knockout, DSPP was not expressed in the dental papilla of the bell stage and in the dental papilla and dental follicle of the secretory phase. The expression position of COL-Ⅰ in the bell and mineralization phase was consistent with that in the wild-type mice. Moreover, the expression of COL-Ⅰ in the dental papilla changed in the secretory stage.@*CONCLUSIONS@#Gene vps4b plays a significant role in the development of tooth germ. The expression of DSPP and COL-Ⅰ may be controlled by gene vps4b and regulates the development of tooth dentin and cementum together with vps4b.


Asunto(s)
Animales , Ratones , ATPasas Asociadas con Actividades Celulares Diversas , Genética , Colágeno , Metabolismo , Complejos de Clasificación Endosomal Requeridos para el Transporte , Genética , Proteínas de la Matriz Extracelular , Metabolismo , Ratones Noqueados , Diente Molar , Odontoblastos , Fosfoproteínas , Metabolismo , Sialoglicoproteínas , Metabolismo , Germen Dentario
5.
Braz. oral res. (Online) ; 33: e058, 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1019608

RESUMEN

Abstract Cementum is the mineralized tissue covering the tooth root that functions in tooth attachment and post-eruptive adjustment of tooth position. It has been reported to be highly similar to bone in several respects but remains poorly understood in terms of development and regeneration. Here, we investigate whether cementocytes, the residing cells in cellular cementum, have the potential to be protagonist in cementum homeostasis, responding to endocrine signals and directing local cementum metabolism. Cells from healthy erupted human teeth were isolated using sequential collagenase/EDTA digestions, and maintained in standard cell culture conditions. A cementocyte-like cell line was cloned (HCY-23, for human cementocyte clone 23), which presented a cementocyte compatible gene expression signature, including the expression of dentin matrix protein 1 ( DMP1 ), sclerostin ( SOST ), and E11/gp38/podoplanin ( E11 ). In contrast, these cells did not express the odontoblast/dentin marker dentin sialoprotein ( DSPP ). HCY-23 cells produced mineral-like nodules in vitro under differentiation conditions, and were highly responsive to inorganic phosphate (Pi). Within the limits of the present study, it can be concluded that cementocytes are phosphate-responsive cells, and have the potential do play a key role in periodontal homeostasis and regeneration.


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Adulto Joven , Marcadores Genéticos/genética , Técnicas de Cultivo de Célula/métodos , Cemento Dental/citología , Fosfatos/farmacología , Fosfoproteínas/análisis , Fosfoproteínas/genética , Sialoglicoproteínas/análisis , Sialoglicoproteínas/genética , Factores de Tiempo , Glicoproteínas de Membrana/análisis , Glicoproteínas de Membrana/genética , Expresión Génica , Línea Celular , Análisis de Varianza , Proteínas de la Matriz Extracelular/análisis , Proteínas de la Matriz Extracelular/genética , Técnica del Anticuerpo Fluorescente , Proteínas Morfogenéticas Óseas/análisis , Proteínas Morfogenéticas Óseas/genética , Cemento Dental/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Diente Molar/citología
6.
J. bras. nefrol ; 40(4): 339-343, Out.-Dec. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-984578

RESUMEN

ABSTRACT Introduction: preeclampsia can be associated with future renal disease. Objectives: To measure changes in renal function overtime in patients with preeclampsia. Methods: urine and serum samples from eleven patients with preeclampsia and eight patients with a normal pregnancy were obtained during pregnancy, postpartum, and 3 years after delivery. Urine podocalyxin, protein, and serum creatinine were measured. Results: after 3 years, there were no significant differences in urinary podocalyxin in patients with or without preeclampsia: 4.34 ng/mg [2.69, 8.99] vs. 7.66 ng/mg [2.35, 13], p = 0.77. The same applied to urinary protein excretion: 81.5 mg/g [60.6, 105.5] vs. 43.2 mg/g [20.9, 139.3] p = 0.23. Serum creatinine was 0.86 mg/dL [0.7, 0.9] vs. 0.8 mg/dL [0.68, 1] p = 0.74 in those with and without preeclampsia. In normal patients, urinary podocalyxin decreased from 54.4 ng/mg [34.2, 76.9] during pregnancy to 7.66 ng/mg [2.35, 13] three years after pregnancy, p = 0.01. Proteinuria decreased from 123.5 mg/g [65.9, 194.8] to 43.2 mg/g [20.9, 139.3], p = 0.12. In preeclampsia patients, urinary podocalyxin decreased from 97.5 ng/mg [64.9, 318.4] during pregnancy to 37.1 ng/mg within one week post-partum [21.3, 100.4] p = 0.05 and 4.34 ng/mg [2.69, 8.99] three years after, p = 0.003. Proteinuria was 757.2 mg/g [268.4, 5031.7] during pregnancy vs. 757.2 mg/g [288.2, 2917] postpartum, p = 0.09 vs. 81.5 mg/g [60.6, 105.5] three years later, p = 0.01. Two patients still had proteinuria after 3 years. Conclusions: in preeclampsia patients, postpartum urinary podocalyxin decreased before proteinuria. After three years, serum creatinine, urinary podocalyxin, and protein tended to normalize, although some patients still had proteinuria.


RESUMO Introdução: a pré-eclâmpsia pode estar associada à doença renal no futuro. Objetivos: medir mudanças na função renal ao longo do tempo em pacientes com pré-eclâmpsia. Métodos: amostras de urina e soro de onze pacientes com pré-eclâmpsia e oito pacientes com gravidez normal foram obtidas durante a gravidez, pós-parto e 3 anos após o parto. Medimos podocalixina na urina, proteína e creatinina sérica. Resultados: após 3 anos, não houve diferenças significativas na podocalixina urinária em pacientes com ou sem pré-eclâmpsia: 4,34 ng/mg [2,69, 8,99] versus 7,66 ng/mg [2,35, 13], p = 0,77. O mesmo se aplicou à excreção urinária de proteínas: 81,5 mg/g [60,6, 105,5] vs. 43,2 mg/g [20,9, 139,3] p = 0,23. A creatinina sérica foi de 0,86 mg/dL [0,7, 0,9] vs. 0,8 mg/dL [0,68, 1] p = 0,74 naqueles com e sem pré-eclâmpsia. Em pacientes normais, a podocalixina urinária diminuiu de 54,4 ng/mg [34,2, 76,9] durante a gestação para 7,66 ng/mg [2,35, 13] três anos após a gravidez, p = 0,01. A proteinúria diminuiu de 123,5 mg/g [65,9, 194,8] para 43,2 mg/g [20,9, 139,3], p = 0,12. Em pacientes com pré-eclâmpsia, a podocalixina urinária diminuiu de 97,5 ng/mg [64,9, 318,4] durante a gravidez para 37,1 ng/mg em uma semana de pós-parto [21,3, 100,4] p = 0,05 e 4,34 ng/mg [2,69, 8,99] três anos depois, p = 0,003. A proteinúria foi de 757,2 mg/g [268.4, 5031.7] durante a gravidez vs. 757,2 mg/g [288.2, 2917] pós-parto, p = 0.09 vs. 81.5 mg/g [60.6, 105.5] três anos depois, p = 0.01. Dois pacientes ainda apresentavam proteinúria após 3 anos. Conclusões: em pacientes com pré-eclâmpsia, a podocalixina urinária pós-parto diminuiu antes da proteinúria. Após três anos, a creatinina sérica, a podocalixina urinária e a proteína tenderam a se normalizar, embora alguns pacientes ainda tivessem proteinúria.


Asunto(s)
Humanos , Femenino , Adulto , Preeclampsia/fisiopatología , Podocitos/patología , Riñón/fisiopatología , Riñón/patología , Preeclampsia/orina , Preeclampsia/sangre , Sialoglicoproteínas/orina , Sialoglicoproteínas/sangre , Factores de Tiempo , Embarazo , Biomarcadores/orina , Biomarcadores/sangre , Estudios Prospectivos , Estudios de Seguimiento
7.
International Journal of Oral Science ; (4): 31-31, 2018.
Artículo en Inglés | WPRIM | ID: wpr-772284

RESUMEN

Phosphophoryn (PP) and dentin sialoprotein (DSP) are the most dominant non-collagenous proteins in dentin. PP is an extremely acidic protein that can function as a mineral nucleator for dentin mineralization. DSP was first identified in 1981, yet its functional significance is still controversial. Historically, these two proteins were considered to be independently synthesized and secreted by dental pulp cells into the developing dentin matrix. However, with the identification of the DSP coding sequence in 1994, followed 2 years later by the finding that the PP coding sequence was located immediately downstream from the DSP sequence, it became immediately clear that DSP and PP proteins were derived from a single DSP-PP (i.e., dentin sialophosphoprotein, DSPP) transcript. Since DSPP cDNA became available, tremendous progress has been made in studying DSP-PP mRNA distribution and DSP generation from the DSP-PP precursor protein at specific cleavage sites by protease tolloid-related-1 (TLR1) or bone morphogenetic protein 1 (BMP1). The functions of DSP-PP and DSP were investigated via DSP-PP knockout (KO) and DSP knockin in DSP-PP KO mice. In addition, a number of in vitro studies aimed to elucidate DSPP and DSP function in dental pulp cells.


Asunto(s)
Animales , Humanos , Ratones , Dentinogénesis , Fisiología , Proteínas de la Matriz Extracelular , Fisiología , Fosfoproteínas , Fisiología , Sialoglicoproteínas , Fisiología
8.
Chinese Journal of Biotechnology ; (12): 1133-1144, 2016.
Artículo en Chino | WPRIM | ID: wpr-242267

RESUMEN

The expression of dentin sialophosphoprotein (DSPP) is the marker for cells differentiated into odontoblasts. This study attempted to analyze the DSPP promoter and build the reporter LacZ expression system driven by this promoter, which allows convenient and quick detection of odontoblast cells. First, we separated the human dental mesenchymal cells in which the expression of DSPP can be effectively induced by dexamethasone. Second, four 5' flanking regions of human DSPP gene (- 4 000-+54, -2 500-+54, -1 447-+54 and -1 027-+54) were analyzed, the results showed that the highest promoter activity lied in the -2 500-+54 region. The promoter activity is reduced when the 5' flanking region was extended from -2 500 to -4 000 bp upstream from the transcription start site; The promoter activity are also decreased when the 5' flanking regions were shorted from -2 500 to -1 447 bp and from -1 447 to -1 027 bp, indicating that potential suppresser elements are lied in the region between -4 000 and -2 500 bp and potential activator elements are lied in the region between -2 500 and -1 027 bp. Then we constructed the lentiviral report vector phDSPP-LacZ containing the -2 500-+ 54 promoter region in front of the LacZ gene. The expression of LacZ was detected using X-Gal staining in both human dental mesenchymal cells and immortalized human dental mesenchymal cells infected with phDSPP-LacZ. The phDSPP-LacZ lentiviral vector may provide a more convenient method to detect the expression of DSPP in human odontogenic differentiation, tooth development and tooth regeneration studies.


Asunto(s)
Humanos , Diferenciación Celular , Proteínas de la Matriz Extracelular , Genética , Genes Reporteros , Operón Lac , Odontoblastos , Biología Celular , Fosfoproteínas , Genética , Regiones Promotoras Genéticas , Sialoglicoproteínas , Genética
9.
Chinese Journal of Medical Genetics ; (6): 34-37, 2016.
Artículo en Chino | WPRIM | ID: wpr-287955

RESUMEN

<p><b>OBJECTIVE</b>To identify the causative mutation in a Chinese family affected with dentinogenesis imperfecta shields type II (DGI-II).</p><p><b>METHODS</b>With informed consent obtained from all participants, peripheral blood or chorionic villi samples were collected from the family members. Genomic DNA was extracted using a standard SDS-proteinase K-phenol/chloroform method. The whole coding region and exon/intron boundaries of the DSPP gene were amplified with polymerase chain reaction (PCR) and subjected to Sanger sequencing. To confirm the pathogenicity of the identified mutation, an Alu I recognition sequence was introduced into the mutant allele using mismatch primers by semi-nested PCR. Restriction fragment length polymorphism (RFLP) analysis was then carried out for all family members and 60 unrelated healthy controls. Meanwhile, mini-DSPP constructs were conducted to confirm the effect of the mutation in vitro.</p><p><b>RESULTS</b>A splicing site mutation, c.52-1G>A, which was located upstream of exon 3, was found in all three patients and the fetus of the proband. Restriction analysis confirmed that all unaffected individuals and the 60 healthy controls did not carry the same mutation. The expression of minigene showed that the exon 3 of the DSPP gene was skipped during the transcription.</p><p><b>CONCLUSION</b>A novel pathogenic splicing-mutation c.52-1G>A has been detected in a Chinese family affected with DGI-II, which enabled prenatal diagnosis for the fetus of the proband.</p>


Asunto(s)
Adulto , Preescolar , Femenino , Humanos , Masculino , Pueblo Asiatico , Genética , Secuencia de Bases , Dentinogénesis Imperfecta , Genética , Exones , Proteínas de la Matriz Extracelular , Genética , Datos de Secuencia Molecular , Linaje , Fosfoproteínas , Genética , Mutación Puntual , Empalme del ARN , Sialoglicoproteínas , Genética
10.
Braz. oral res. (Online) ; 30(1): e20, 2016. tab, graf
Artículo en Inglés | LILACS | ID: biblio-951968

RESUMEN

Abstract The aim of this study was to evaluate whether medium modification improves the odontogenic differentiation of human dental pulp stem cells (DPSC) in vitro and in vivo. DPSC isolated from human impacted third molar teeth were analysed for clusters of differentiation with flow cytometry. Odontogenic differentiation was stimulated by medium modification with the addition of bone morphogenetic protein 2 (BMP2). The expression of dentin sialophosphoprotein, dentin matrix protein 1, enamelysin/matrix metalloproteinase 20 and the phosphate-regulating gene with homologies to endopeptidases on the X chromosome of the cells were analysed with RT-PCR at 7, 14 and 21 days. Then, DPSC were transplanted on the back of immunocompromised mice via a hydroxyapatite tricalcium phosphate scaffold, and the structure of the formed tissue was investigated. The cells were identified as mesenchymal stem cells with a 98.3% CD73 and CD90 double-positive cell rate. The increase in mineralization capacity and expression of human enamel-dentin specific transcripts proportional to the culture period were determined after differentiation. Six weeks after transplantation, an osteo-dentin matrix was formed in the group in which odontogenic differentiation was stimulated, and the odontogenic characteristics of the matrix were confirmed by histological examination and RT-PCR analysis. Odontogenic differentiation of the isolated and characterized human DPSC was improved with medium modification by the addition of BMP2 in vitro and in vivo. The defined medium and applied technique have a potential use for forming reparative dentin in the future, but the effects of the method should be investigated in long-term studies.


Asunto(s)
Humanos , Animales , Adulto , Ratones , Adulto Joven , Células Madre/citología , Diferenciación Celular/efectos de los fármacos , Medios de Cultivo/química , Pulpa Dental/citología , Proteína Morfogenética Ósea 2/farmacología , Fosfoproteínas/análisis , Sialoglicoproteínas/análisis , Factores de Tiempo , Diferenciación Celular/fisiología , Células Cultivadas , Reproducibilidad de los Resultados , Proteínas de la Matriz Extracelular/análisis , Actinas/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Trasplante de Células Madre/métodos , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Metaloproteinasa 20 de la Matriz/análisis , Endopeptidasa Neutra Reguladora de Fosfato PHEX/análisis , Proteína Morfogenética Ósea 2/química , Citometría de Flujo , Odontogénesis/efectos de los fármacos , Odontogénesis/fisiología
11.
Braz. oral res. (Online) ; 30(1): e120, 2016. tab, graf
Artículo en Inglés | LILACS | ID: biblio-951977

RESUMEN

Abstract This study was designed to determine the in vivo performance of three different materials as scaffolds for dental pulp stem cells (DPSC) undergoing induced odontogenic differentiation. An odontogenic medium modified by the addition of recombinant human bone morphogenetic protein 2 was used in the experimental groups to induce differentiation. Mesenchymal stem cell medium was used in the control groups. DPSC were transplanted onto the backs of mice via three scaffolds: copolymer of L-lactide and DL-lactide (PLDL), copolymer of DL-lactide (PDL) and hydroxyapatite tricalcium phosphate (HA/TCP). The expression levels of dentin sialo-phosphoprotein (DSPP), dentin matrix protein-1 (DMP1), enamelysin/matrix metalloproteinase 20 (MMP20) and phosphate-regulating gene with homologies to endopeptidases on X chromosome (PHEX) were analysed using RT-PCR. The expressions in the experimental groups were compared to those in the control groups. The transcript expressions at 6 and 12 weeks were significantly different for all scaffolds (p < 0.05), except for the expression of DSPP in the PLDL group with regard to the time variable. Although there was a decrease in the expression of enamelysin/MMP20 in PLDL and HA/TCP at 12 weeks, all other expressions increased and reached their highest level at 12 weeks. The highest DSPP expression was in the PDL group (p < 0.05). The highest expression of DMP1 was detected in the HA/TCP group (p < 0.05). The highest expression of PHEX was in the PLDL group (p < 0.05). Consequently, PLDL and PDL seemed to be promising scaffold candidates for odontogenic regeneration at least as HA-TCP, when they were applied with the DPSC induced for odontogenic differentiation.


Asunto(s)
Humanos , Animales , Polímeros/química , Células Madre/fisiología , Diferenciación Celular/fisiología , Pulpa Dental/citología , Andamios del Tejido/química , Fosfoproteínas/análisis , Sialoglicoproteínas/análisis , Factores de Tiempo , Materiales Biocompatibles/química , Fosfatos de Calcio/química , Expresión Génica , Reproducibilidad de los Resultados , Proteínas de la Matriz Extracelular/análisis , Durapatita/química , Técnicas de Cultivo de Célula , Esmalte Dental/química , Dentina/química , Dioxanos/química , Metaloproteinasa 20 de la Matriz/análisis , Endopeptidasa Neutra Reguladora de Fosfato PHEX/análisis
12.
Chinese Journal of Stomatology ; (12): 725-730, 2015.
Artículo en Chino | WPRIM | ID: wpr-259453

RESUMEN

<p><b>OBJECTIVE</b>To investigate the effect of bioactivity glass 45S5- silk fibroin(BG45S5- SF) membrane on growth, proliferation and differentiation of human dental pulp stem cells(hDPSC), and to provide new ideas and method for the regeneration of pulp-dentine complex.</p><p><b>METHODS</b>hDPSC seed on pure silk fibroin membrane (protein membrane group) and BG45S5-SF membrane with different concentrations(1 000, 5 000 mg/L, composite membrane group A and B, respectively) were prepared, and the materials were incubated in cell culture fluid for 24 h. No material membrane orifice plate was used as blank control group. Contact angle meter was used to measure surface contact angle of protein membrane and composite membrane group(each group had three repeated holes). Cell proliferation was assessed by cell counting kit- 8 on the 4, 7, 14, and 21 days. The state of adhesion and growth of hDPSC on the materials surface was evaluated by scanning electron microscopy and cytoskeleton staining; and alkaline phosphatase (ALP) activity was measured to evaluate the cell differentiation potential. The expression of odontoblastic differentiation-related genes was measured by real-time PCR.</p><p><b>RESULTS</b>Surface contact angle of the protein membrane group and composite membrane group A and group B were 89.51° ± 0.12°, 70.32° ± 0.07° and 71.31° ± 0.09° respectively. hDPSC adhered well on each materials surface on the 7, 14, 21 days, ALP activity and differentiation genes of composite membrane group A and B rised more significantly than the blank control group and protein membrane group did (P<0.05). Dentin matrix protein1(DMP- 1), dentin sialoprotein(DSP), ALP, osteocalcin(OC) mRNA expression reached peak on the 14 days in group A, and in group B on the 21 days. Bone sialoprotein(BSP) mRNA expression in both group A and B reached peak on the 21 days.</p><p><b>CONCLUSIONS</b>BG45S5- SF membrane is able to support the proliferation and showed the potential of odontoblastic differentiation for hDPSC. This finding suggests that BG45S5-SF membrane was a kind of tissue engineering film material with the regeneration potential for pulp-dentine complex.</p>


Asunto(s)
Humanos , Adhesión Celular , Técnicas de Cultivo de Célula , Diferenciación Celular , Proliferación Celular , Cerámica , Usos Terapéuticos , Pulpa Dental , Biología Celular , Proteínas de la Matriz Extracelular , Metabolismo , Fibroínas , Usos Terapéuticos , Vidrio , Membranas Artificiales , Odontoblastos , Biología Celular , Osteocalcina , Metabolismo , Fosfoproteínas , Metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Sialoglicoproteínas , Metabolismo , Células Madre , Biología Celular , Ingeniería de Tejidos
13.
West China Journal of Stomatology ; (6): 75-79, 2015.
Artículo en Chino | WPRIM | ID: wpr-261134

RESUMEN

<p><b>OBJECTIVE</b>This study aims to investigate the effects of mineral trioxide aggregate (MTA) and calcium hydroxide on proliferation and differentiation of human pulp cells from primary and permanent teeth.</p><p><b>METHODS</b>Cell proliferation was detected by methyl thiazolyl tetrazolium (MTT) assay. The mRNA expression levels of dentinogenesis-related factors, including alkaline phosphatase (ALP) and dentin sialophosphoprotein (DSPP), and odontoclastogenesis-related factors, such as osteo- protegerin (OPG) and receptor activator of NF-κB ligand (RANKL), were determined by real time polymerase chain reac- tion (PCR).</p><p><b>RESULTS</b>Primary and permanent pulp cells treated with calcium hydroxide exhibited significantly lower proli- feration rates than the control cells (P<0.01). By contrast, the MTA-treated group showed significantly higher proliferation rates than the control group (P<0.01). Real time PCR results showed that calcium hydroxide-treated primary pulp cells exhi- bited significantly decreased ALP, DSPP, and OPG expression compared with the control group (P<0.01). Conversely, the MTA-treated group displayed significantly increased ALP, DSPP, and OPG expression (P<0.01). Calcium hydroxide-treated primary pulp cells also exhibited significantly upregulated RANKL expression (P < 0.01); by contrast, MTA-treated cells did not show any change in RANKL expression (P>0.05). Likewise, MTA-treated permanent pulp cells showed significantly upregulated ALP and DSPP expression (P < 0.01). However, the calcium hydroxide-treated group remained almost the same as the control group (P > 0.05). Neither MTA nor calcium hydroxide affected OPG and RANKL expression in per- manent pulp cells (P > 0.05).</p><p><b>CONCLUSION</b>MTA is more suitable as a pulp-capping agent, particularly in primary teeth, than calcium hydroxide.</p>


Asunto(s)
Humanos , Compuestos de Aluminio , Compuestos de Calcio , Hidróxido de Calcio , Diferenciación Celular , Proliferación Celular , Pulpa Dental , Dentición Permanente , Combinación de Medicamentos , Proteínas de la Matriz Extracelular , Óxidos , Fosfoproteínas , Sialoglicoproteínas , Silicatos
14.
Dental press j. orthod. (Impr.) ; 19(6): 62-69, Nov-Dec/2014. graf
Artículo en Inglés | LILACS | ID: lil-732434

RESUMEN

OBJECTIVE: The aim of this study is to determine a protocol of gingival crevicular fluid protein extraction used for the first dimension of 2-DE gels. It also aims at conducting a review on the current candidates for protein markers of this pathology, all of which may be used to prevent the disease. METHODS: Gingival crevicular fluid was collected from two groups of 60 patients each, with and without external root resorption. Samples were extracted by means of various methods of protein extraction. SDS-PAGE gels were used to assess the quality of the method which was subsequently tested during isoelectric focusing of 2-DE gels taken from samples of patients with and without the disease. RESULTS: Milli-Q ultrapure ice cold water, without precipitation for gingival crevicular fluid protein extraction, proved the method with greatest sharpness to detect protein bands. Additionally, it allowed two-dimensional electrophoresis to be performed. CONCLUSION: The new protein extraction protocol does not interfere in isoeletric focusing of 2-DE gels. Furthermore, it provides the greatest sharpness in detecting protein bands of SDS-PAGE gels. This will allow mapping and searching of new external root resorption markers, particularly due to the difficulty in carrying out molecular tests with the current candidates for protein markers. .


OBJETIVO: o objetivo desse trabalho foi determinar o protocolo de extração proteica do fluido crevicular gengival, que pudesse ser utilizado para a realização da primeira dimensão dos géis 2-DE, bem como fazer uma revisão dos atuais candidatos a marcadores proteicos dessa patologia que podem ser utilizados na prevenção dessa doença. MÉTODOS: foi coletado o fluido crevicular gengival de dois grupos de 60 pacientes, com e sem a reabsorção radicular externa. As amostras foram extraídas por diversos métodos de extração proteica e utilizados géis SDS-PAGE para aferir a qualidade do método, que posteriormente foi testado durante a realização da focalização isoelétrica dos géis 2-DE, de amostras de pacientes com e sem a patologia. RESULTADOS: a utilização de água Milli-Q gelada ultrapura, sem nenhuma precipitação para a extração proteica do fluido crevicular gengival, foi o método com maior nitidez das bandas proteicas, além de permitir a realização da eletroforese bidimensional. CONCLUSÕES: o novo protocolo de extração proteica não interfere na focalização durante a realização dos géis 2-DE, além de maior nitidez na resolução das bandas proteicas dos géis SDS-PAGE. Isso permitirá o mapeamento e busca de novos marcadores da reabsorção radicular externa, tendo em vista a dificuldade de realização de testes moleculares com os atuais candidatos a marcadores proteicos. .


Asunto(s)
Adolescente , Adulto , Femenino , Humanos , Masculino , Adulto Joven , Proteínas de la Matriz Extracelular/análisis , Líquido del Surco Gingival/química , Resorción Radicular/metabolismo , Biomarcadores/análisis , Electroforesis en Gel Bidimensional/métodos , Electroforesis en Gel de Poliacrilamida/métodos , Focalización Isoeléctrica/métodos , Fosfoproteínas/análisis , Sialoglicoproteínas/análisis , Agua/química
15.
Arq. bras. endocrinol. metab ; 58(6): 630-639, 08/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-721394

RESUMEN

Objective: We sought to test the effect of different dosages of pioglitazone (PIO) on the glomerular expression of podocalyxin and urinary sediment podocalyxin excretion and to explore the potential renoprotective mechanism. Materials and methods: Type 1 diabetes induced with streptozotocin (65 mg/kg) in 36 male Sprague-Dawley rats were randomly allocated to be treated with vehicle or 10, 20, 30 mg/kg/d PIO respectively for 8 weeks. Eight rats were enrolled in the normal control group. Results: At 8th week, rats were sacrificed for the observation of kidney injury through electron microscope. Glomerular podocalyxin production including mRNA and protein were determined by RT-PCR and immunohistochemistry respectively. Levels of urinary albumin excretion and urinary sediment podocalyxin, kidney injury index were all significantly increased, whereas expression of glomerular podocalyxin protein and mRNA were decreased significantly in diabetic rats compared to normal control. Dosages-dependent analysis revealed that protective effect of PIO ameliorated the physiopathological changes and reached a peak at dosage of 20 mg/kg/d. Conclusion: PIO could alleviate diabetic kidney injury in a dose-dependent pattern and the role may be associated with restraining urinary sediment podocalyxin excretion and preserving the glomerular podocalyxin expression. .


Objetivo: Buscamos testar os efeitos de diferentes doses de pioglitazona (PIO) sobre a expressão glomerular de podocalixina e sobre a excreção de podocalixina em células do sedimento urinário, além de explorar o potencial mecanismo de proteção renal. Materiais e métodos: O diabetes tipo 1 foi induzido em 36 ratos Sprague-Dawley machos com estreptozotocina (65 mg/kg). Os animais foram tratados apenas com o veículo, ou com 10, 20, 30 mg/kg/d de PIO por 8 semanas. Oito ratos foram colocados no grupo controle. Resultados: Na oitava semana, os ratos foram sacrificados para se observar a lesão renal em microscopia eletrônica. A produção de podocalixina glomerular, incluindo mRNA e proteína, foi determinada por RT-PCR e imuno-histoquímica, respectivamente. Os níveis urinários de albumina e podocalixina nas células do sedimento urinário e o índice de lesão renal estavam todos significativamente aumentados, enquanto a expressão glomerular da proteína podocalixina e do mRNA estava significativamente diminuída em ratos diabéticos comparados com o controle normal. A análise dos efeitos dose-dependentes revelou que o efeito protetor da PIO melhorou as mudanças fisiopatológicas e atingiu um pico na dose de 20 mg/kg/dia. Conclusão: A PIO pode melhorar a injúria renal de forma dose-dependente e este papel pode estar associado com a prevenção da excreção de podocalixina nas células do sedimento urinário e com a preservação da expressão glomerular de podocalixina. .


Asunto(s)
Animales , Masculino , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Podocitos/patología , Sialoglicoproteínas/metabolismo , Tiazolidinedionas/uso terapéutico , HDL-Colesterol/sangre , HDL-Colesterol/efectos de los fármacos , LDL-Colesterol/sangre , LDL-Colesterol/efectos de los fármacos , Diabetes Mellitus Experimental/patología , Inmunohistoquímica , Glomérulos Renales/efectos de los fármacos , Glomérulos Renales/lesiones , Glomérulos Renales/ultraestructura , Microscopía Electrónica , Distribución Aleatoria , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa , ARN Mensajero/aislamiento & purificación , Sialoglicoproteínas/genética , Sialoglicoproteínas/orina , Triglicéridos/sangre
16.
The Korean Journal of Helicobacter and Upper Gastrointestinal Research ; : 173-181, 2013.
Artículo en Coreano | WPRIM | ID: wpr-30352

RESUMEN

BACKGROUND/AIMS: Sulglycotide is a non-systemic drug, used in the treatment of peptic ulcer and gastritis. The aim of this study was to assess the therapeutic effect and safety of Gliptide (sulglycotide 200 mg) in comparison with Mucosta (rebamipide 100 mg) for treatment of gastritis. MATERIALS AND METHODS: Two hundred and three symptomatic patients with erosive gastritis at endoscopy were randomized to receive sulglycotide or rebamipide for four weeks. Therapeutic effects of the drugs for gastritis were evaluated by follow up endoscopic scoring systems and clinical symptoms. We also sought possible adverse effects of the two drugs. RESULTS: Gliptide (sulglycotide) and Mucosta (rebamipide) treatment in symptomatic gastritis resulted in endoscopic improvement rates of gastritis by 52.0%, 60.6% in intention-to-treat (ITT) analysis, 53.4%, 61.1% in per protocol (PP) analysis, which means therapeutic effects was not different between the two groups. The symptom improvement rates in the sulglycotide and rebamipide treated group were 57.3%, 57.5% in ITT analysis, 54.7%, 58.8% in PP analysis, which mean statistically no significant difference between the two groups. Endoscopic findings such as cure rates of erosion, edema, improvement rates of redness, hemorrhage were not significantly different between the two groups. No statistical significant differences were observed for adverse events between the two groups. The results of 95% CIs for the difference in endoscopic improvement rate and symptom improvement rate met the criteria for the non-inferiority of sulglycotide to rebamipide. CONCLUSIONS: These results demonstrate that Gliptide (sulglycotide) was not inferior to Mucosta (rebamipide) for endoscopic and symptomatic improvements for symptomatic erosive gastritis.


Asunto(s)
Humanos , Alanina , Edema , Endoscopía , Estudios de Seguimiento , Gastritis , Hemorragia , Úlcera Péptica , Quinolonas , Sialoglicoproteínas
17.
Journal of Southern Medical University ; (12): 1512-1516, 2013.
Artículo en Chino | WPRIM | ID: wpr-232763

RESUMEN

<p><b>OBJECTIVE</b>To regenerate dentin-pulp complex by tissue engineering with human stem cells from apical papilla cells (SCAP) as the seed cells.</p><p><b>METHODS</b>SCAP was separated from from normal human impacted third molars with immature roots by outgrowth culture. The cells were then cultured in the differentiation medium for 3 weeks or in normal medium for 60 days, and analyzed for mineralization potential by Alizarin red staining. The osteo/odontogenic markers including alkaline phosphatase (ALP), bone sialoprotein (BSP), osteocalcin (OC) and dentin sialoprotein (DSP) were investigated by immunofluorescence staining and reverse transcription-polymerase chain reaction. The co-cultured mixture of SCAP and HA/TCP, or HA/TCP alone was implanted subcutaneously on the back of nude mice for 8 weeks, and the implants were collected and examined by HE and immunohistochemical staining.</p><p><b>RESULTS</b>Round alizarin red-positive nodules formed in the isolated cells after cell culture in the differentiation medium for 3 weeks or in normal medium for 60 days with positive staining for osteo/odontogenic markers. SCAP with HA/TCP could regenerate pulp-dentin complex-like tissue in nude mice. The cells near the dentin-like tissue were positive for DSP. No mineral tissue was found in mice receiving HA/TCP implantation.</p><p><b>CONCLUSIONS</b>SCAP may serve as a promising seed cell for dentin-pulp complex tissue engineering.</p>


Asunto(s)
Adolescente , Adulto , Animales , Femenino , Humanos , Ratones , Adulto Joven , Fosfatasa Alcalina , Técnicas de Cultivo de Célula , Diferenciación Celular , Técnicas de Cocultivo , Papila Dental , Biología Celular , Pulpa Dental , Biología Celular , Proteínas de la Matriz Extracelular , Sialoproteína de Unión a Integrina , Ratones Desnudos , Odontogénesis , Fisiología , Osteocalcina , Fosfoproteínas , Sialoglicoproteínas , Células Madre , Química , Fisiología , Ingeniería de Tejidos , Métodos
18.
Chinese Journal of Stomatology ; (12): 27-31, 2013.
Artículo en Chino | WPRIM | ID: wpr-260184

RESUMEN

<p><b>OBJECTIVE</b>To determine the effects of KH2PO4 on the odonto- and osteogenic differentiation potential of human stem cells from apical papillae (SCAP) in vitro.</p><p><b>METHODS</b>SCAP were isolated and cultured respectively in alpha minimum essential medium (α-MEM) or α-MEM containing 1.8 mmol/L KH2PO4. Alkaline phosphatase (ALP) activity, alizarin red staining, real-time reverse transcription polymerase chain reaction (RT-PCR) and Western blotting were used to examine the odonto and osteogenic potential of SCAP in the two media.</p><p><b>RESULTS</b>SCAP cultured in α-MEM containing 1.8 mmol/L KH2PO4 exhibited a higher ALP activity [(0.370 ± 0.013) Sigma unit×min(-1)×mg(-1)] at day 3 than control group [(0.285 ± 0.008) Sigma unit×min(-1)×mg(-1)] and KH2PO4-treated SCAP formed more calcified nodules at day 5 [(0.539 ± 0.007) µg/g] and day 7 [(1.617 ± 0.042) µg/g] than those in normal medium [(0.138 ± 0.037) µg/g, P < 0.01]. The expression of odonto- and osteogenic markers were significantly up-regulated after the stimulation of KH2PO4 at day 3 and 7 respectively, as compared with control group.</p><p><b>CONCLUSIONS</b>1.8 mmol/L KH2PO4 can promote the odonto and osteogenic differentiation potential of human SCAP.</p>


Asunto(s)
Humanos , Diferenciación Celular , Células Cultivadas , Pulpa Dental , Biología Celular , Proteínas de la Matriz Extracelular , Metabolismo , Osteoblastos , Biología Celular , Osteocalcina , Metabolismo , Fosfatos , Farmacología , Fosfoproteínas , Metabolismo , Compuestos de Potasio , Farmacología , Sialoglicoproteínas , Metabolismo , Células Madre , Biología Celular , Metabolismo
19.
Chinese Journal of Stomatology ; (12): 672-678, 2013.
Artículo en Chino | WPRIM | ID: wpr-274160

RESUMEN

<p><b>OBJECTIVE</b>To investigate the expression of octamer-binding transcription factor 4A(Oct4A) in human dental pulp cells(DPC)and the effect of Oct4A on the proliferation and multiple differentiation ability of DPC.</p><p><b>METHODS</b>Expression of Oct4A in DPC was detected by realtime quantitative PCR(RT-qPCR). siRNA-Oct4A was constructed and transfected (50 nmol/L) into DPC with Lipofectamine(TM) RNAiMAX for 24, 48, 72, 96 and 120 h. The proliferation rate of DPC was examined using cell counting kit 8 (CCK-8) assay. The alizarin red staining was used to observe the formation of calcification nodules in DPC with 14 d of osteogenic induction, and oil red O staining to observe the formation of lipid droplet in DPC with 14 d of adipogenic induction. The expression of osteogenesis-related genes dentin sialophosphoprotein (DSPP) and adipogenesis-related genes lipoprotein lipase (LPL) was detected using RT-qPCR and Western blotting.</p><p><b>RESULTS</b>The expression of Oct4A reached the peak in P3 DPC (2.10 ± 0.10), which was 2.10 times as much as that in P1 (P = 0.000 vs. P1 and P7), and decreased along passages. The interference efficiency of DPC transfection peaked at 72 h (69.7%). Compared with control group and negative control group (IR-siRNA), the proliferation rate and multiple differentiation ability of DPC in interference group (Oct4A-siRNA) were downregulated (P = 0.000), and DSPP and LPL in DPC from interference group significantly decreased (P = 0.000).</p><p><b>CONCLUSIONS</b>The interference of Oct4A significantly downregulated the cell proliferation rate and multilineage differentiation capability of DPC.</p>


Asunto(s)
Adolescente , Adulto , Humanos , Adulto Joven , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Pulpa Dental , Biología Celular , Metabolismo , Proteínas de la Matriz Extracelular , Metabolismo , Lipoproteína Lipasa , Metabolismo , Factor 3 de Transcripción de Unión a Octámeros , Genética , Metabolismo , Osteogénesis , Genética , Fisiología , Fosfoproteínas , Metabolismo , ARN Mensajero , Metabolismo , ARN Interferente Pequeño , Genética , Sialoglicoproteínas , Metabolismo , Transfección
20.
Chinese Journal of Contemporary Pediatrics ; (12): 817-821, 2013.
Artículo en Chino | WPRIM | ID: wpr-345700

RESUMEN

<p><b>OBJECTIVE</b>To study the expression of histone acetyltransferases (HATs) and histone deacetylases (HDACs) in children with tetralogy of Fallot (TOF), and to investigate the role of histone acetylation and acetylation-related enzymes in the pathogenesis of TOF.</p><p><b>METHODS</b>Myocardial tissue samples in the TOF group were obtained from 46 children with TOF who underwent radical operation, and myocardial tissue samples in the control group were obtained from 16 children who suffered accidental deaths and had no cardiac anomalies as shown by autopsy. The acetylation of H3K9, H3K18 and H3K27 was evaluated by immunohistochemistry. The mRNA expression of HATs and HDACs in the myocardium was measured by real-time PCR. The correlation between mRNA expression of HATs and HDACs and histone acetylation was analyzed.</p><p><b>RESULTS</b>Compared with the control group, the TOF group showed significantly increased acetylation of H3K9 (P=0.0165) and significantly decreased acetylation of H3K18 (P=0.0048) and H3K27 (P=0.0084). As to 4 HATs and 6 HDACs, the mRNA expression of EP300 and CBP was significantly higher in the TOF group than in the control group (P=0.025; P=0.017), and there was no significant difference in the mRNA expression of other HATs and HDACs between the two groups. The correlation analysis revealed a positive correlation between H3K9 acetylation and mRNA expression of EP300 (r=0.71, P<0.01) and CBP (r=0.72, P<0.01).</p><p><b>CONCLUSIONS</b>Upregulated mRNA expression of EP300 and CBP may be associated with increased H3K9 acetylation, suggesting that EP300 and CBP might affect cardiac development by regulating H3K9 acetylation.</p>


Asunto(s)
Femenino , Humanos , Lactante , Masculino , Acetilación , Proteína p300 Asociada a E1A , Genética , Histona Acetiltransferasas , Genética , Histona Desacetilasas , Genética , Histonas , Metabolismo , Miocardio , Metabolismo , Fragmentos de Péptidos , Genética , ARN Mensajero , Sialoglicoproteínas , Genética , Tetralogía de Fallot , Metabolismo
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