463 research outputs found

    In vitro wearing away of orthodontic brackets and wires in different conditions: A review

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    Introduction: The release of metallic ions from orthodontic brackets and wires typically depends on their quality (chemical composition) and the medium to which they are exposed, e.g., acidic, alkaline, substances with a high fluoride concentration, etc. This review examines corrosion and wear of orthodontic brackets, wires, and arches exposed to different media, including: beverages (juices), mouthwashes and artificial saliva among others, and the possible health effects resulting from the release of metallic ions under various conditions. Objective: This review aims to determine the exposure conditions that cause the most wear on orthodontic devices, as well as the possible health effects that can be caused by the release of metallic ions under various conditions. Sources: A search was carried out in the Scopus database, for articles related to oral media that can corrode brackets and wires. The initial research resulted in 8,127 documents, after applying inclusion and exclusion criteria, 76 articles remained. Conclusion: Stainless steel, which is commonly used in orthodontic devices, is the material that suffers the most wear. It was also found that acidic pH, alcohols, fluorides, and chlorides worsen orthodontic material corrosion. Further, nickel released from brackets and wires can cause allergic reactions and gingival overgrowth into patients.Fil: Espinoza Montero, Patricio J.. Pontificia Universidad Católica del Ecuador; EcuadorFil: Montero Jiménez, Marjorie Elizabeth. Pontificia Universidad Católica del Ecuador; Ecuador. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; ArgentinaFil: Fernández, Lenys. Pontificia Universidad Católica del Ecuador; EcuadorFil: Paz, Jose Luis. Universidad Nacional Mayor de San Marcos; PerúFil: Piñeiros, José Luis. Pontificia Universidad Católica del Ecuador; EcuadorFil: Ceballos, Sandra Macías. Universidad Central del Ecuador; Ecuado

    Effect of Sphaerosporella brunnea mycorrhizas on mycorrhization of Quercus ilex × Tuber melanosporum

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    It is generally accepted that Sphaerosporella brunnea is a significant ectomycorrhizal contaminant in nurseries producing plants mycorrhized with various species of Tuber, and subsequently in truffières after outplanting. At the University of Alcalá, Spain, 397 small plants of Quercus ilex which were mycorrhized with Tuber melanosporum were inadvertently contaminated with S. brunnea, and this contamination was then monitored for 2 years. Sixty percent of the plants were contaminated and had S. brunnea ascomata on the surface of the container on one or several occasions. However, a Spearman test provided no evidence that S. brunnea mycorrhizas affected T. melanosporum mycorrhization whereas other contaminating ectomycorrhizal fungi significantly did. Therefore, it appears that S. brunnea is not detrimental to plants which are well mycorrhized with T. melanosporum

    DNA damage induced during mitosis undergoes DNA repair synthesis.

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    Understanding the mitotic DNA damage response (DDR) is critical to our comprehension of cancer, premature aging and developmental disorders which are marked by DNA repair deficiencies. In this study we use a micro-focused laser to induce DNA damage in selected mitotic chromosomes to study the subsequent repair response. Our findings demonstrate that (1) mitotic cells are capable of DNA repair as evidenced by DNA synthesis at damage sites, (2) Repair is attenuated when DNA-PKcs and ATM are simultaneously compromised, (3) Laser damage may permit the observation of previously undetected DDR proteins when damage is elicited by other methods in mitosis, and (4) Twenty five percent of mitotic DNA-damaged cells undergo a subsequent mitosis. Together these findings suggest that mitotic DDR is more complex than previously thought and may involve factors from multiple repair pathways that are better understood in interphase

    Mesenchymal Stem Cell Migration and Proliferation Are Mediated by Hypoxia-Inducible Factor-1 alpha Upstream of Notch and SUMO Pathways

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    Mesenchymal stem cells (MSCs) are effective in treating several pathologies. We and others have demonstrated that hypoxia or hypoxia-inducible factor 1 alpha (HIF-1 alpha) stabilization improves several MSC functions, including cell adhesion, migration, and proliferation, thereby increasing their therapeutic potential. To further explore the mechanisms induced by HIF-1 alpha in MSCs, we studied its relationship with Notch signaling and observed that overexpression of HIF-1 alpha in MSCs increased protein levels of the Notch ligands Jagged 1-2 and Delta-like (Dll) 1, Dll3, and Dll4 and potentiated Notch signaling only when this pathway was activated. Crosstalk between HIF and Notch resulted in Notch-dependent migration and spreading of MSCs, which was abolished by gamma-secretase inhibition. However, the HIF-1-induced increase in MSC proliferation was independent of Notch signaling. The ubiquitin family member, small ubiquitin-like modifier (SUMO), has important functions in many cellular processes and increased SUMO1 protein levels have been reported in hypoxia. To investigate the potential involvement of SUMOylation in HIF/Notch crosstalk, we measured general SUMOylation levels and observed increased SUMOylation in HIF-1-expressing MSCs. Moreover, proliferation and migration of MSCs were reduced in the presence of a SUMOylation inhibitor, and this effect was particularly robust in HIF-MSCs. Immunoprecipitation studies demonstrated SUMOylation of the intracellular domain of Notch1 (N1ICD) in HIF-1-expressing MSCs, which contributed to Notch pathway activation and resulted in increased levels of N1ICD nuclear translocation as assessed by subcellular fractionation. SUMOylation of N1ICD was also observed in HEK293T cells with stabilized HIF-1 alpha expression, suggesting that this is a common mechanism in eukaryotic cells. In summary, we describe, for the first time, SUMOylation of N1ICD, which is potentiated by HIF signaling. These phenomena could be relevant for the therapeutic effects of MSCs in hypoxia or under conditions of HIF stabilization.This work was supported, in part, by grants from the Instituto de Salud Carlos III PI13/00414, PI16/0107, RE-TICS RD12/0019/0025 to P.S. and RETICS RD12/0019/0003 (TERCEL) to J.L.D.L.P cofunded by FEDER ``una manera de hacer Europa. It was also supported by the Regenerative Medicine Program of Instituto de Salud Carlos III and Valencian Community to Centro de Investigacion Principe Felipe. The authors are grateful to Dr. A. Dorronsoro for critical review of the work and Dr. K McCreath for manuscript editing.S

    Simulación dinámica para el dimensionado de una instalación basada en energías renovables que abastece energéticamente a una construcción Pasivhaus de emisiones cero

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    Dimensionamiento energético de una construcción en tres escenarios climáticos por medio del software HOMER ENERGY.<br /

    A systematic literature review and expert consensus on risk factors associated to infection progression in adult patients with respiratory tract or rectal colonisation by carbapenem-resistant Gram-negative bacteria

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    Multi-drug resistance; Risk factor; ColonizationResistencia a múltiples fármacos; Factor de riesgo; ColonizaciónResistència a múltiples fàrmacs; Factor de risc; ColonitzacióObjective. Risk factors (RFs) associated with infection progression in patients already colonised by carbapenem-resistant Gram-negative bacteria (CRGNB) have been addressed in few and disperse works. The aim of this study is to identify the relevant RFs associated to infection progression in patients with respiratory tract or rectal colonisation. Material and methods. A systematic literature review was developed to identify RFs associated with infection progression in patients with CRGNB respiratory tract or rectal colonisation. Identified RFs were then evaluated and discussed by the expert panel to identify those that are relevant according to the evidence and expert’s experience. Results. A total of 8 articles were included for the CRGNB respiratory tract colonisation and 21 for CRGNB rectal colonisation, identifying 19 RFs associated with pneumonia development and 44 RFs associated with infection progression, respectively. After discussion, the experts agreed on 13 RFs to be associated with pneumonia development after respiratory tract CRGNB colonisation and 33 RFs to be associated with infection progression after rectal CRGNB colonisation. Respiratory tract and rectal colonisation, previous stay in the ICU and longer stay in the ICU were classified as relevant RF independently of the pathogen and site of colonisation. Previous exposure to antibiotic therapy or previous carbapenem use were also common relevant RF for patients with CRGNB respiratory tract and rectal colonisation. Conclusion. The results of this study may contribute to the early identification of CRGNB colonized patients at higher risk of infection development, favouring time-to-effective therapy and improving health outcomes.This study was funded by Shionogi S.L.U

    Validación del Münchner Alkoholismus Test Subjektiv para el diagnóstico de alcoholismo en población adulta

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    ResumenObjetivoValidar la parte subjetiva del cuestionario MALT (Münchner Alkoholismus Test) para el diagnóstico de alcoholismo en población adulta.DiseñoEstudio descriptivo de validación de un instrumento diagnóstico.EmplazamientoDos centros de atención primaria, un centro de drogodependencias y un centro de atención a alcohólicos, ubicados en la provincia de Córdoba, España.ParticipantesSeiscientos catorce pacientes con edades de entre 18 y 80 años.Mediciones principalesMediante entrevista personal se realizaron los cuestionarios MALT, AUDIT (Alcohol Use Disorders Identification Test) y el SCAN (Schedules for clinical assessment in Neuropsychiatry). Se analizó la fiabilidad interna, la reproducibilidad, la validez criterial (patrón de referencia: criterios del Manual Diagnóstico y Estadístico de los Trastornos Mentales IV [DSM-IV]) y la validez convergente.ResultadosLa edad media de la población fue de 43 años (desviación estándar de 1,43). El 17,4% presentó síndrome de dependencia alcohólica. Los coeficientes kappa de los ítems del test oscilaban entre 0,568 y 0,969. El alfa de Cronbach del MALT completo fue de 0,919; el alfa de Cronbach del MALT subjetivo fue de 0,939, y el alfa de Cronbach del MALT objetivo fue de 0,737. El área bajo la curva de eficacia diagnóstica para el MALT-S fue de 0,946 y para el MALT completo fue de 0,953. Para un punto de corte de 4, la sensibilidad del MALT-S fue del 92,6% y la especificidad fue del 90,8%. El coeficiente de correlación del MALT-S y del AUDIT fue de 0,86 (p<0,001).ConclusionesEl MALT subjetivo es un cuestionario tan válido y fiable como el MALT completo, por lo que puede ser utilizado aisladamente para la detección y el diagnóstico de alcoholismo.AbstractObjectiveTo validate the subjective part of the MALT questionnaire (MALT-S) for the detection of alcoholism among the adult population.DesignA descriptive study on the validation of a diagnostic tool.SettingTwo primary health care centres, a centre for drug addicts and a centre for alcoholics in Cordoba (Spain).Participants614 patients, between 18 and 80 years.MeasurementsThrough personal interviews the MALT, AUDIT and SCAN questionnaires were given. The internal reliability, stability and both the criterion and convergent validity were analysed.ResultsThe mean age of the population’ was 43±1.43 (SD) years and 17.4% of them showed Alcohol Dependence Syndrome. The Kappa coefficients of the test items ranged from 0.568 to 0.969. The Cronbach alpha of the complete MALT was 0.919, of the MALT-S, 0.939 and of the MALT-O, 0.737. The area under the ROC curve of the MALT-S was 0.946 and that of the complete MALT was 0.953. For a cut-off point of four, the sensitivity of the MALT-S is 92.7% while its specificity was 90.9%. The correlation coefficient of the MALT-S and AUDIT was 0.86 (P<0.001).ConclusionsThe MALT-S questionnaire is as valid and reliable as the complete MALT; therefore, it can be used on its own for the diagnosis of alcoholism

    European traditional tomatoes galore: a result of farmers' selection of a few diversity-rich loci

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    A comprehensive collection of 1254 tomato accessions, corresponding to European traditional and modern varieties, early domesticated varieties, and wild relatives, was analyzed by genotyping by sequencing. A continuous genetic gradient between the traditional and modern varieties was observed. European traditional tomatoes displayed very low genetic diversity, with only 298 polymorphic loci (95% threshold) out of 64 943 total variants. European traditional tomatoes could be classified into several genetic groups. Two main clusters consisting of Spanish and Italian accessions showed higher genetic diversity than the remaining varieties, suggesting that these regions might be independent secondary centers of diversity with a different history. Other varieties seem to be the result of a more recent complex pattern of migrations and hybridizations among the European regions. Several polymorphic loci were associated in a genome-wide association study with fruit morphological traits in the European traditional collection. The corresponding alleles were found to contribute to the distinctive phenotypic characteristic of the genetic varietal groups. The few highly polymorphic loci associated with morphological traits in an otherwise a low-diversity population suggests a history of balancing selection, in which tomato farmers likely maintained the morphological variation by inadvertently applying a high selective pressure within different varietal types
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