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Electrical contacts and interconnections are critical components for all electronic devices. Bendable electrodes with enhanced electro-mechanical properties are highly desirable to develop innovative wearable electronic devices. Herein we report on a fabrication method for robust bendable coatings based on titanium nitride (TiN) thin films and silver nanowires (Ag NWs). TiN and TiN-AgNWs nanocomposites were deposited on polyethylene terephthalate (PET) substrates using a plasma enhanced pulsed laser deposition (PLD) technique. The resulting TiN coatings exhibit excellent adhesion to PET and their sheet resistance can be tuned using a dual frequency PLD process and further decreased by incorporating Ag NWs into the TiN layers. Sample sheet resistance was decreased down to values as low as [Formula: see text] corresponding to the formation of TiN-AgNWs nanocomposites. The electro-mechanical robustness of TiN based coatings were evaluated by four-probe resistance measurements in situ under cyclic bending tests. We show that the TiNAgNWs nanocomposites surpass both ITO and Ag NWs coatings in terms of mechanical robustness and electrical conductivity respectively. These nanocomposites withstand high strain fatigue loading up to ϵ = 2.6%, keeping R S below 5 Ω/â¡. The data demonstrates that the incorporation of Ag NWs in TiN coatings improve the mechanical robustness, limiting the crack growth and propagation, with low optical transmittance decrease (≈11%). These results indicate that Ag NWs based nanocomposites are attractive materials for flexible electronic devices.
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BACKGROUND: Retrospective studies to assess the distribution of oral diseases (ODs) are helpful in estimating the prevalence of oral diagnoses in the population, and thus help in preventive and curative services. Prevalence and frequency data for ODs are available from many countries, but information from Chile is scarce. MATERIAL AND METHODS: This study investigated the frequency of OD in a Chilean population. For this, we included all patients treated at the University of Talca (UTALCA, Chile) between 2001 and 2014. Patient characteristics were retrieved from medical files. To contextualize our results, we conducted a systematic review (SystRev) using Publish or Perish software (PoP), Google Scholar and MEDLINE/PubMed. RESULTS: One hundred sixty-six ODs were diagnosed, and the most prevalent groups were soft tissue tumours, epithelial pathology and salivary gland pathology. Individually, irritation fibroma, oral lichen planus (OLP) and mucocele were the most common diagnoses. ODs frequently affected unspecified parts of the mouth (including cheek, vestibule and retromolar area), gum, lips, tongue and palate. In the SystRev, the more studied diagnoses were leukoplakia, OLP and recurrent aphthous stomatitis; prevalent lesions included Fordyce's spots, recurrent aphthous stomatitis and fissured tongue. Chilean patients and SistRev shared almost all ODs. CONCLUSIONS: The results reflect ODs diagnosed in a specialized service of oral pathology and medicine in Chile and will allow the establishment of preventive/curative policies, adequate health services and dentistry curriculum.
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Enfermedades de la Boca/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Chile/epidemiología , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Factores de Tiempo , Adulto JovenRESUMEN
MoO3 and MoO3-x nanostructures were grown in a simple one-step process by direct evaporation of MoO3 pellets from a tungsten resistive source in presence of helium or hydrogen at pressures from 100 to 1200 Pa. This method uses no templates, catalysts or oxidizing agents. It leads to one dimensional (1-D) crystalline nanostructures mixed with amorphous material in variable ratios. Amorphous structures grew preferentially when hydrogen was used as carrier gas while crystalline material predominated when helium was used. In fact, only crystalline structures were found when the evaporation was carried out under a helium pressure of 600 Pa with source temperatures between 763 and 910 degrees C. Hydrated MoO3 phases with different water concentrations were preferentially formed using hydrogen. X-ray photoelectron spectroscopy detected only molybdenum in its +6 oxidation state in the samples grown under helium, exhibiting the same chemical composition of the source material. Molybdenum in its +6 as well as its +5 oxidation states was detected in the samples obtained under hydrogen at 600 Pa. Hydroxyl groups were identified in samples grown using both gases. The effect of the helium pressure on the growth kinetics and crystallinity of the samples is discussed according to the kinetics conditions (supersaturation, evaporation, cooling and convection rates) driving to the formation of nanostructures in the inert-gas condensation. Finally, the effect of hydrogen on the growth of MoO3 is discussed.
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The present investigation reports the modification of Ti substrates by a plasma technique to enhance their physio-chemical properties as biocompatible substrates for the deposition of artificial membranes. For that purpose, nitrogen ions are implanted into Ti substrate using the plasma immersion ion implantation & deposition (PIII&D) technique in a capacitively coupled radio frequency plasma. The plasma was characterized using optical emission spectroscopy, together with radio frequency compensated Langmuir probe, while the ion current towards the substrate was measured during the implantation process using an opto-electronic device. X-ray photoelectron spectroscopy (XPS) was used for chemical analysis of the surface, confirming the presence of δ-TiN. The penetration depth of the nitrogen ions into the Ti substrate was measured using secondary ions mass spectroscopy (SIMS) while the morphological changes were observed using atomic force microscopy (AFM). A calorimetric assay was used to prove that the TiN samples maintain the biocompatibility of the untreated Ti surface with its native oxide layer. The ion implantation increases the load bearing ability of Ti surface by the formation of α-Ti(N) and δ-TiN phases on the sub-surface of Ti, and maintains the bio compatibility of Ti surface. After the plasma treatment a thin layer of chitosan (CH) was deposited in order to provide a moisturizing matrix for the artificial membrane of 1,2-dipalmitoyl-sn-3- phosphor glycerocholine (DPPC). The CH and subsequently the DPPC were deposited on the plasma deposited TiN substrate by using physical vapor deposition. The formation of artificial membranes was confirmed by AFM, measuring the topography at different temperatures and performing force curves.
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Materiales Biocompatibles/química , Membranas Artificiales , Nitrógeno/química , Gases em Plasma/química , Titanio/química , 1,2-Dipalmitoilfosfatidilcolina/química , Animales , Materiales Biocompatibles/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Quitosano/química , Ratones , Propiedades de SuperficieRESUMEN
Molybdenum trioxide nanostructures were grown by direct evaporation of MoO3 from a tungsten boat resistively heated in the presence of hydrogen or helium as carrier gas at pressures from 100 to 600 Pa. Crystalline structures such as, nanoribbons, nanofibers, nanoneedles and nanoparticles were obtained at source temperatures below 900 degrees C. On the other hand, at source temperatures above 1000 degrees C, nanoporous structures were obtained. The latter were found more often when hydrogen was used as carrier gas.
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Cristalización/métodos , Gases/química , Molibdeno/química , Nanoestructuras/química , Nanoestructuras/ultraestructura , Nanotecnología/métodos , Óxidos/química , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Tamaño de la Partícula , Porosidad , Propiedades de SuperficieRESUMEN
Introducción: El quiste odontogénico glandular (QOG) tiene una diversidad de características epidemiológicas, clínicas e imagenológicas. El propósito de la presente revisión fue analizarla epidemiología, clínica, imagenología junto con la agresividad, tratamiento, seguimiento y recidiva de QOG en la literatura actual. Materiales y métodos: Se realizó una búsqueda sistemática de casos clínicos de QOG publicados entre 2012-2022 en PubMed, Web of Science y Science Direct que tuvieran información epidemiológica, clínica e imagenológica junto a su confirmación histopatológica a través de descripción e imágenes. Resultados: Se incluyeron 27 artículos con 30QOG. Los QOG se presentaron entre los 7 y 78 años. Su tiempo de evolución promedio fue de un año. Se observaron mayoritariamente en región posterior de mandíbula y sin sintomatología. Mayoritariamente fueron radiolúcidos, uniloculares, con bordes definidos y corticalizados y presentaron expansión ósea. Presentaron características agresivas como gran tamaño, perforación ósea y los dientes involucrados tendieron a tenerespacio periodontal infiltrado, desplazamiento y rizálisis. La mayoría de los QOG se trataron con enucleación y no recidivaron. Conclusiones: Se observaron QOG con características que difieren de la literatura clásica en edad, tiempo de evolución, sintomatología, patrón imagenológico, presentación bilateral y ubicación. La imagenología del QOG tiene un comportamiento por lo general, agresivo. En tanto, su agresividad estuvo asociada con su mayor tamaño, borramiento y/o infiltración cortical, perforación ósea, espacio periodontal infiltrado, rizalisis externa y al compromiso de estructuras anatómicas adyacentes. Teniendo en cuenta estas características, los tratamientos de descompresión y exéresis, junto a seguimientos menores a 5 años podrían recidivar. (AU)
Introduction: Glandular odontogenic cyst (GOC) has a diversity of epidemiological, clinical and imaging characteristics. The purpose of this review was to analyze the epidemiology, clinic, and imaging, along with aggressiveness, treatment, follow-up, and recurrence of GOC in the current literature. Materials and methods: A systematic search for clinical cases of GOC published between 2012-2022 was conducted in PubMed, Web of Science and Science Direct. Epidemiological, clinical and imaging information, along with their histopathological confirmation through description and images had to be present in the articles. Results: 27 articles with 30 GOC were included. GOC was found to be present between 7 and 78 years. Its average evolution time was one year. They were observed mostly in the posterior mandible and were asymptomatic. They were mostly radiolucent, unilocular, with defined and corticated borders and presented bone expansion. They presented aggressive characteristics such as larger size, bone perforation and the teeth involved tended to have infiltrated periodontal space, displacement and root resorption. GOC were mostly treated with enucleation and did not present recurrence. Conclusions: GOC was observed with atypical characteristics, which differ from classical literature in terms of age, time of evolution, symptomatology, imaging pattern, bilateral presentation and location. Imaging of QOG generally has an aggressive behavior. Its aggressiveness was associated with its larger size, cortical effacement and/or infiltration, bone perforation, infiltrated periodontal space, root resorption, and involvement of adjacent anatomical structures. Considering the characteristics mentioned above, decompression and excision treatments, together with follow-up of less than 5 years, could lead to recurrence. (AU)
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Humanos , Quiste Odontogénico Calcificado , Diagnóstico por Imagen , Práctica Profesional , Maxilar , Mandíbula , OdontólogosRESUMEN
INTRODUCTION: The congenital transmission of Trypanosoma cruzi (T. cruzi) is responsible for one-third of new Chagas disease cases each year. During congenital transmission, the parasite breaks down the placental barrier formed by the trophoblast, basal laminae and villous stroma. The observation that only 5% of infected mothers transmit the parasite to the fetus implies that the placenta may impair parasite transmission. The trophoblast undergoes continuous epithelial turnover, which is considered part of innate immunity. Therefore, we propose that T. cruzi induces differentiation in the trophoblast as part of a local antiparasitic mechanism of the placenta. METHODS: We analyzed ß-human chorionic gonadotropin (ß-hCG) and syncytin protein expression in HPCVE and BeWo cells using immunofluorescence and western blotting. Additionally, ß-hCG secretion into the culture medium was measured by ELISA. We assessed the differentiation of trophoblastic cells in BeWo cells using the two-color fusion assay and by determining desmoplakin re-distribution. RESULTS: T. cruzi trypomastigotes induce ß-hCG secretion and protein expression as well as syncytin protein expression in HPCVE and BeWo cells. Additionally, the parasite induces the trophoblast fusion of BeWo cells. DISCUSSION: T. cruzi induces differentiation of the trophoblast, which may contribute to increase the trophoblast turnover. The turnover could be a component of local antiparasitic mechanisms in the human placenta.
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Diferenciación Celular , Enfermedad de Chagas/patología , Placenta/parasitología , Trofoblastos/parasitología , Trypanosoma cruzi , Línea Celular , Enfermedad de Chagas/metabolismo , Gonadotropina Coriónica Humana de Subunidad beta/metabolismo , Femenino , Productos del Gen env/metabolismo , Humanos , Placenta/metabolismo , Placenta/patología , Embarazo , Proteínas Gestacionales/metabolismo , Trofoblastos/metabolismo , Trofoblastos/patologíaRESUMEN
Pathogenic processes have been identified that could associate chronic stress and cancer, but these findings have not been observed in oral cancer. This study examined the role of chronic restraint stress on the incidence and severity of OSCC induced with 4-nitroquinoline-1-oxide (4-NQO) in the tongues of CF-1 mice. One hundred twenty CF-1 male mice were divided into 4 groups: (A) received two treatments - restraint stress and induction of chemical carcinogenesis (n = 50); (B) induction of chemical carcinogenesis, without restraint stress (n = 50); (C) restraint stress (n = 10); and (D) control (n = 10). After 30 weeks, tongues were dissected and analyzed by conventional histopathology. The severity of OSSC was analyzed according to the International Histological Classification of Tumors and Bryne's Multifactorial Grading System for the Invasive Tumor Front (ITF). Chronic stress induction was confirmed by plasma corticosterone levels. Results showed that chronic stress was induced with movement restriction (p ≤ 0.05, Mann-Whitney U-test). However, chronic stress did not increase the incidence (p > 0.05, Chi-square) or severity (p > 0.05, Mann-Whitney U-test) of the 4-NQO-induced OSSC in the tongues of CF-1 mice. These results suggest that there is no relationship between chronic stress (induced in mice by restraint) and the incidence and severity of OSSC.