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1.
Polymers (Basel) ; 16(11)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38891480

RESUMEN

BACKGROUND: Sealing the peri-implant tissue is a determining factor for long-term implant survival. In the transmucosal region, the cervical fraction of the prosthetic crown is in contact with these tissues, so mucointegration will also be influenced by the biomaterial used for the prosthetic restoration. This study aims to compare the tissue response generated by definitive restorative materials and polymeric materials from a histological point of view. METHODS: This study performed an observational prospective cohort study in which biopsies of the peri-implant mucosa were taken after placement of implant-supported prosthetic restorations made of different materials (zirconium oxide, lithium disilicate, and PMMA). RESULTS: A statistically significant difference was observed in the increase in the thickness of the non-keratinized epithelium when comparing the definitive materials (zirconium oxide/lithium disilicate) vs. the provisional material (PMMA) and in the number of collagen fibers when comparing zirconium oxide and lithium disilicate. CONCLUSIONS: This study found that zirconia is the material that presents the most adequate biological response of peri-implant tissues. It shows a lower intensity of inflammatory cellular content, a total normality in the number of collagen fibers (the arrangement of the fibers is normal in 90% of the cases), and vascular proliferation of connective tissue in 83% of the cases. These parameters make it a material with a predictable response. Similarly, only the following slight statistically significant differences between the definitive and provisional materials are observed, indicating that the biological response generated by the provisional material (PMMA) is not very different from that obtained with the placement of the definitive restoration.

2.
J Clin Med ; 13(7)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38610713

RESUMEN

Introduction: The COVID-19 pandemic has induced profound societal and healthcare transformations globally. Material and methods: This multicenter retrospective study aimed to assess potential shifts in the epidemiology and management of oromaxillofacial trauma requiring surgical intervention over a 1-year period encompassing the onset of the COVID-19 pandemic, in comparison to the preceding year. The parameters investigated included age, sex, injury mechanisms, fractured bones, and treatment modalities. The statistical significance was set at p < 0.05. Results: A notable 39.36% reduction in oromaxillofacial fractures was identified (p < 0.001), with no significant alterations in sex distribution, types of fractured bones, or treatment modalities. An appreciable increase in mean age was observed (35.92 vs. 40.26) (p = 0.006). Analysis of the causes of oromaxillofacial trauma revealed diminished incidents of interpersonal violence (41% vs. 35%) and sports-related injuries (14% vs. 8%), alongside an escalation in cases attributed to falls (27% vs. 35%), precipitation events (2% vs. 5%), and traffic accidents (12% vs. 13%). The mandible emerged as the most frequently fractured bone. Conclusion: In conclusion, the COVID-19 pandemic has decreased the number of maxillofacial fractures treated surgically and has changed the epidemiology and the etiology of facial traumas.

3.
Sensors (Basel) ; 22(17)2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36081061

RESUMEN

Road surface properties have a major impact on pavement's life service conditions. Nowadays, contactless techniques are widely used to monitor road surfaces due to their portability and high precision. Among the different possibilities, laser profilometers are widely used, even though they have two major drawbacks: spatial information is missed and the cost of the equipment is considerable. The scope of this work is to show the methodology used to develop a fast and low-cost system using images taken with a commercial camera to recover the height information of the road surface using Convolutional Neural Networks. Hence, the dataset was created ad hoc. Based on photometric theory, a closed black-box with four light sources positioned around the surface sample was built. The surface was provided with markers in order to link the ground truth measurements carried out with a laser profilometer and their corresponding intensity values. The proposed network was trained, validated and tested on the created dataset. Three loss functions where studied. The results showed the Binary Cross Entropy loss to be the most performing and the best overall on the reconstruction task. The methodology described in this study shows the feasibility of a low-cost system using commercial cameras based on Artificial Intelligence.


Asunto(s)
Inteligencia Artificial , Redes Neurales de la Computación
4.
PLoS One ; 9(12): e114837, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25514808

RESUMEN

The Shoc2 protein has been implicated in the positive regulation of the Ras-ERK pathway by increasing the functional binding interaction between Ras and Raf, leading to increased ERK activity. Here we found that Shoc2 overexpression induced sustained ERK phosphorylation, notably in the case of EGF stimulation, and Shoc2 knockdown inhibited ERK activation. We demonstrate that ectopic overexpression of human Shoc2 in PC12 cells significantly promotes neurite extension in the presence of EGF, a stimulus that induces proliferation rather than differentiation in these cells. Finally, Shoc2 depletion reduces both NGF-induced neurite outgrowth and ERK activation in PC12 cells. Our data indicate that Shoc2 is essential to modulate the Ras-ERK signaling outcome in cell differentiation processes involved in neurite outgrowth.


Asunto(s)
Factor de Crecimiento Epidérmico/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Neuritas/metabolismo , Animales , Línea Celular Tumoral , Activación Enzimática/genética , Células HEK293 , Humanos , Péptidos y Proteínas de Señalización Intracelular/biosíntesis , Sistema de Señalización de MAP Quinasas , Células PC12 , Fosforilación , Interferencia de ARN , ARN Interferente Pequeño , Ratas , Proteínas ras/genética , Proteínas ras/metabolismo
5.
PLoS One ; 6(2): e16787, 2011 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-21364986

RESUMEN

Sprouty and Spred proteins have been widely implicated in the negative regulation of the fibroblast growth factor receptor-extracellular regulated kinase (ERK) pathway. In considering the functional role of these proteins, we explored their effects on ERK activation induced by cyclopentenone prostanoids, which bind to and activate Ras proteins. We therefore found that ectopic overexpression in HeLa cells of human Sprouty2, or human Spred1 or 2, inhibits ERK1/2 and Elk-1 activation triggered by the cyclopentenone prostanoids PGA(1) and 15d-PGJ(2). Furthermore, we found that in HT cells that do not express Sprouty2 due to hypermethylation of its gene-promoter, PGA(1)-provoked ERK activation was more intense and sustained compared to other hematopoietic cell lines with unaltered Sprouty2 expression. Cyclopentenone prostanoids did not induce Sprouty2 tyrosine phosphorylation, in agreement with its incapability to activate tyrosine-kinase receptors. However, Sprouty2 Y55F, which acts as a defective mutant upon tyrosine-kinase receptor stimulation, did not inhibit cyclopentenone prostanoids-elicited ERK pathway activation. In addition, Sprouty2 did not affect the Ras-GTP levels promoted by cyclopentenone prostanoids. These results unveil both common and differential features in the activation of Ras-dependent pathways by cyclopentenone prostanoids and growth factors. Moreover, they provide the first evidence that Sprouty and Spred proteins are negative regulators of the ERK/Elk-1 pathway activation induced not only by growth-factors, but also by reactive lipidic mediators.


Asunto(s)
Ciclopentanos/farmacología , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/fisiología , Proteínas de la Membrana/fisiología , Prostaglandinas/farmacología , Proteínas Represoras/fisiología , Proteínas Adaptadoras Transductoras de Señales , Línea Celular Tumoral , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Activación Enzimática/efectos de los fármacos , Activación Enzimática/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Células HeLa , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Modelos Biológicos , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Transfección
6.
Endocrinol Nutr ; 56(10): 452-7, 2009 Dec.
Artículo en Español | MEDLINE | ID: mdl-20114015

RESUMEN

BACKGROUND: Iodine deficiency in pregnant women may result in substantial and irreversible impairment in fetal brain development, even from the first few weeks of pregnancy. OBJECTIVE: To assess the nutritional iodine status of pregnant women in our health area and its relationship with dietary factors and thyroid function and to suggest treatment guidelines. PATIENTS AND METHOD: A study in 164 pregnant women in early pregnancy was carried out. Data on urinary iodine concentrations were gathered from 24-hour urine samples. Data on anthropometric parameters and thyroid function were included. Information on dietary habits in the previous week was collected using a nutritional questionnaire. All data were obtained before iodine supplements were administered. RESULTS: The median urinary iodine concentration was 92 [p25-p75 range, 71-139] microg/l. Seventy-eight percent of urinary iodine values were under 150 microg/l. Women who took iodized salt had higher levels of urinary iodine concentrations than women without iodized salt intake. CONCLUSIONS: Seventy-eight percent of pregnant women in our health area were iodine deficient. Iodized salt intake is related to iodine sufficiency and to increased urinary iodine concentrations. Measures to increase intake of iodized salt among the population should be implemented. Iodized salt supplements should be systematically prescribed in women from the beginning of pregnancy.


Asunto(s)
Yodo/deficiencia , Adulto , Enfermedades Carenciales/epidemiología , Femenino , Humanos , Estado Nutricional , Embarazo , Prevalencia , España/epidemiología
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