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1.
J Dent ; 149: 105283, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39096997

RESUMO

OBJECTIVE: The aim of this study was to evaluate the effect of an adhesive loaded with 0.2 % copper (Cu) and 5 % zinc oxide (ZnO) nanoparticles (Nps) on its adhesive properties and enzymatic activity at the hybrid layer ex vivo in a randomized clinical model. METHODS: Fifteen patients participated in this study, and a total of 30 third molars were used. Occlusal cavities (4 × 4 × 2 mm) were made in each tooth, and randomly divided into 2 groups: (i) Experimental group: commercial adhesive loaded with 0.2wt % CuNps and 5wt % ZnONps; and (ii) Control Group: non-loaded commercial adhesive. Teeth were restored with resin composite. Thirty days later, extractions were performed. Extracted teeth were longitudinally sectioned. Nps in powder were characterized by field emission scanning electron microscope (FE-SEM) and energy dispersive X-ray (EDX) analysis. Microtensile bond strength (µTBS), degree of conversion (DC), and nanoleakeage (NL) tests were executed. In situ zymography (Zym) was performed to evaluate the gelatinolytic activity at the hybrid layer. Student's t-test (α = 0.05) was applied for all tests. RESULTS: µTBS and DC did not show significant differences (p > 0.05) between both groups. However, NL and gelatinolytic activity at the hybrid layer showed significant values (p < 0.05) for experimental group in comparison with control group. CONCLUSION: The addition of 0.2 % CuNps and 5 % ZnONps to a universal adhesive decreases NL and gelatinolytic activity at the hybrid layer, without jeopardizing its adhesive properties. SIGNIFICANCE: This randomized clinical trial with ex vivo analysis demonstrate that a commercial adhesive modified with 0.2wt % Cu and 5wt % ZnO Nps that does not affect its adhesive properties, reducing gelatinolytic activity and nanoleakage at the hybrid layer, which should contribute to an improvement of long term bonding-dentine clinical performance.


Assuntos
Resinas Compostas , Cobre , Colagem Dentária , Microscopia Eletrônica de Varredura , Resistência à Tração , Óxido de Zinco , Humanos , Óxido de Zinco/química , Cobre/química , Colagem Dentária/métodos , Resinas Compostas/química , Nanopartículas/química , Adesivos Dentinários/química , Dentina/efeitos dos fármacos , Dentina/enzimologia , Teste de Materiais , Masculino , Cimentos de Resina/química , Adulto , Feminino , Propriedades de Superfície , Cimentos Dentários/química , Dente Serotino , Restauração Dentária Permanente/métodos , Espectrometria por Raios X
2.
Sci Total Environ ; 872: 162086, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36764536

RESUMO

Artificial light at night (ALAN) is a pervasive but still under-recognized driver of global change. In coastal settings, a large majority of the studies assessing ALAN impacts has focused on individual species, even though it is unclear whether results gathered from single species can be used to predict community-wide responses. Similarly, these studies often treat species as single life-stage entities, ignoring the variation associated with distinct life stages. This study addresses both limitations by focusing on the effects of ALAN on a sandy beach community consisting of species with distinct early- and late-life stages. Our hypothesis was that ALAN alters community structure and these changes are mediated by individual species and also by their ontogenetic stages. A field experiment was conducted in a sandy beach of north-central Chile using an artificial LED system. Samples were collected at different night hours (8-levels in total) across the intertidal (9-levels) over several days in November and January (austral spring and summer seasons). The abundance of adults of all species was significantly lower in ALAN treatments. Early stages of isopods showed the same pattern, but the opposite was observed for the early stages of the other two species. Clear differences were detected in the zonation of these species during natural darkness versus those exposed to ALAN, with some adult-juvenile differences in this response. These results support our hypothesis and document a series of changes affecting differentially both early and late life stages of these species, and ultimately, the structure of the entire community. Although the effects described correspond to short-term responses, more persistent effects are likely to occur if ALAN sources become established as permanent features in sandy beaches. The worldwide growth of ALAN suggests that the scope of its effect will continue to grow and represents a concern for sandy beach systems.


Assuntos
Ecossistema , Poluição Luminosa , Chile , Estações do Ano , Luz
3.
J Comput Aided Mol Des ; 37(2): 75-90, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36494599

RESUMO

Chagas disease, also known as American trypanosomiasis, is a neglected tropical disease caused by the protozoa Trypanosoma cruzi, affecting nearly 7 million people only in the Americas. Polyamines are essential compounds for parasite growth, survival, and differentiation. However, because trypanosomatids are auxotrophic for polyamines, they must be obtained from the host by specific transporters. In this investigation, an ensemble of QSAR classifiers able to identify polyamine analogs with trypanocidal activity was developed. Then, a multi-template homology model of the dimeric polyamine transporter of T. cruzi, TcPAT12, was created with Rosetta, and then refined by enhanced sampling molecular dynamics simulations. Using representative snapshots extracted from the trajectory, a docking model able to discriminate between active and inactive compounds was developed and validated. Both models were applied in a parallel virtual screening campaign to repurpose known drugs as anti-trypanosomal compounds inhibiting polyamine transport in T. cruzi. Montelukast, Quinestrol, Danazol, and Dutasteride were selected for in vitro testing, and all of them inhibited putrescine uptake in biochemical assays, confirming the predictive ability of the computational models. Furthermore, all the confirmed hits proved to inhibit epimastigote proliferation, and Quinestrol and Danazol were able to inhibit, in the low micromolar range, the viability of trypomastigotes and the intracellular growth of amastigotes.


Assuntos
Doença de Chagas , Tripanossomicidas , Trypanosoma cruzi , Humanos , Putrescina/uso terapêutico , Ligantes , Danazol/uso terapêutico , Quinestrol/uso terapêutico , Poliaminas/química , Poliaminas/uso terapêutico , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Proteínas de Membrana Transportadoras/uso terapêutico , Tripanossomicidas/farmacologia , Tripanossomicidas/química
4.
Environ Sci Pollut Res Int ; 29(24): 35977-35985, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35060027

RESUMO

Artificial Light at Night (ALAN) is expanding worldwide, and the study of its influence remains limited mainly to documenting impacts, overlooking the variation in key characteristics of the artificial light such as its intensity. The potential dose-response of fitness-related traits to different light intensities has not been assessed in sandy beach organisms. Hence, this study explored dose-responses to ALAN by exposing the intertidal sandy beach isopod Tylos spinulosus to a range of light intensities at night: 0 (control), 20, 40, 60, 80 and 100 lx. We quantified the response of this species at the molecular (RNA:DNA ratios), physiological (absorption efficiency) and organismal (growth rate) levels. Linear and non-linear regressions were used to explore the relationship between light intensity and the isopod response. The regressions showed that increasing light intensity caused an overall ~ threefold decline in RNA:DNA ratios and a ~ threefold increase in absorption efficiency, with strong dose-dependent effects. For both response variables, non-linear regressions also identified likely thresholds at 80 lx (RNA:DNA) and 40 lx (absorption efficiency). By contrast, isopod growth rates were unrelated (unaltered) by the increase in light intensity at night. We suggest that ALAN is detrimental for the condition of the isopods, likely by reducing the activity and feeding of these nocturnal organisms, and that the isopods compensate this by absorbing nutrients more efficiently in order to maintain growth levels.


Assuntos
Isópodes , Poluição Luminosa , Animais , Causalidade , DNA , Isópodes/efeitos da radiação , RNA
5.
Mar Pollut Bull ; 168: 112416, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33957496

RESUMO

Many coastal processes are regulated by day/night cycles and are expected to be altered by Artificial Light at Night (ALAN). The goal of this study was to assess the influence of ALAN on the settlement rates of intertidal barnacles. A newly designed settlement plate equipped with a small central LED light source was used to quantify settlement rates in presence/absence of ALAN conditions. "ALAN plates" as well as regular settlement plates were deployed in the mid rocky intertidal zone. Both ALAN and control plates collected early and late settlers of the barnacles Notochthamalus scabrosus and Jehlius cirratus. Early settlers (pre-metamorphosis cyprids) were not affected by ALAN. By contrast, the density of late settlers (post-metamorphosis spats) was significantly lower in ALAN than in control plates for both species, suggesting detrimental ALAN impacts on the settlement process. The new ALAN plates represent an attractive and alternative methodology to study ALAN effects.


Assuntos
Thoracica , Animais , Ecossistema , Luz , Metamorfose Biológica
6.
Front Chem ; 9: 671980, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017821

RESUMO

This study focuses on examining the isomerization of allyl alcohol using ruthenium (Ru) supported on alumina as a heterogeneous catalyst. The synthesized Ru/Al solids were characterized by various characterization techniques. The content of Ru was estimated by the energy dispersive x-ray technique. The x-ray diffraction (XRD) confirmed the presence of phases in the support and active species in the catalysts. The surface area of the support after Ru impregnation and the pore volume were determined by nitrogen physisorption. The analysis of programmed temperature (TPR and TPO) shows different redox sites which is confirmed by XPS. The catalytic results suggest a dependence on the amount of available metallic Ru, as well as the importance of the continuous regeneration of the metal using H2 to achieve a good conversion of the allyl alcohol. For comparison purposes, the commercial Ru on alumina 5% (CAS 908142) was used. The results show up to 68% alcohol conversion and 27% yield of the isomerization product using Ru(1,5.4h)/Al catalyst in comparison with 86% conversion and 39% yield of the isomerization product using CAS 908142. In contrast, our catalysts always presented higher TOF values (149-160) in comparison with CAS 908142 (101).

7.
Int. j. med. surg. sci. (Print) ; 7(4): 1-12, dic. 2020. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1151790

RESUMO

La parálisis facial periférica es un trastorno neurológico que tiene consecuencias motoras y sensoriales y que afecta al nervio facial. Ocasiona alteraciones en la acción de los músculos del rostro, en la secreción de saliva, lágrimas y en el sentido del gusto.El objetivo de esta publicación es dar cuenta de un caso en el que se realizó un tratamiento con terapias combinadas mínimamente invasivas junto con el uso de láserterapia de baja potencia, en un paciente femenino, 52 años de edad, con antecedentes médicos relevantes, derivada para evaluación estética. La paciente presenta una parálisis facial moderada sin resolver. Fue sometida a láserterapia con longitud de onda (808 nm) y una energía de 3 Joules por sesión en el lado afectado, complementada con toxina botulinica Tipo A, en el lado sano.El tratamiento de parálisis facial periférica con terapias combinadas mínimamente invasivas ha mostrado ser una herramienta útil terapéutica de las secuelas faciales. A su vez, la terapia de fotobiomodulación con láser de baja potencia es prometedora como coadyuvante en el proceso de reparación nerviosa lo que permitiría la recuperación funcional del nervio facial a mediano y largo plazo.


Peripheral Facial Palsy is a neurological disorder that has motor and sensory consequences and affects the facial nerve. It causes alterations in the action of the muscles of the face, in the secretion of saliva, tears, and in the sense of taste.The objective of this publication is to report a case in which a treatment with minimally invasive combined therapies was performed together with the use of low-level laser therapy, in a 52-year-old female patient. With relevant medical history, referred for aesthetic evaluation and with unresolved moderate facial paralysis. She was subjected to laser therapy with wavelength (808 nm) and an energy of 3 Joules per session on the affected side, supplemented with Botulinum Toxin Type A, on the healthy side.The treatment of peripheral facial paralysis with minimally invasive combined therapies has proven to be a useful therapeutic tool for facial sequelae. In turn, low-level laser photobiomodulation therapy is promising as an adjunct in the nerve repair process, which would allow functional recovery of the facial nerve in the medium and long term.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Terapia com Luz de Baixa Intensidade , Paralisia Facial/radioterapia
8.
Int. j. med. surg. sci. (Print) ; 7(4): 1-12, dic. 2020. ilus
Artigo em Espanhol | LILACS | ID: biblio-1151807

RESUMO

Los implantes dentales son ampliamente usados para el reemplazo de piezas dentarias y se han convertido en el "gold standard" de las terapias protésicas en odontología. Dado el mayor uso de éstos, las investigaciones epidemiológicas recientes han demostrado elevadas tasas de prevalencia de enfermedad periimplantaria. En el presente estudio se presentan tres casos clínicos diagnosticados con periimplantitis. Todos los casos presentaron aumento de la profundidad al sondaje periimplantario en relación a controles anteriores, supuración, sangramiento al sondaje y pérdida ósea confirmada a través de tomografía computada cone beam. El tratamiento indicado para todos los casos fue una terapia conjunta entre un tratamiento mecánico mediante ultrasonido con la utilización de puntas plásticas (P.I EMS®, Suiza) y la terapia con láser. Para la laserterapia se utilizó un equipo de láser diodo de 940 nm (Biolase®, USA) con una potencia de 2 W en modo CW, utilizando una punta de 300 µm. El láser de diodo no daña la superficie de titanio y es capaz de descontaminar las superficies rugosas de los implantes. En este reporte, el uso de una terapia combinada mecánica y láser fue efectiva en todos los casos. En los controles clínicos, la mucosa periimplantaria no presentó signos de supuración ni sangramiento, y la profundidad al sondaje también se vió disminuída. El nivel óseo se controló a través de una tomografía computada cone beam y no se evidenciaron cambios significativos. En la actualidad, la evidencia clínica para el tratamiento periimplantario mediante la fototerapia todavía es limitada. Sin embargo, el láser ofrece un enfoque técnico novedoso que es completamente diferente de los instrumentos mecánicos y tiene varios efectos beneficiosos, por lo que puede desempeñar un papel importante, en la resolución de la peri-implantitis.


Dental implants are widely used for the replacement of teeth and have become the "gold standard" of prosthetic therapies in dentistry. Given the increased use of these, recent epidemiological investigations have shown high prevalence rates of peri-implant disease. In the present study, three clinical cases diagnosed with peri-implantitis are presented. All cases presented increased depth to peri-implant probing in relation to previous controls, suppuration, bleeding and bone loss confirmed by cone beam computed tomography. The treatment indicated for all cases was a joint therapy between a mechanical ultrasound treatment with the use of plastic tips (P.I EMS®, Switzerland) and laser therapy. For laser therapy, a 940 nm diode laser equipment was used (Biolase®, USA) with a power of 2W in continuous laser beam mode, using a 300 µm tip. The diode laser does not damage the titanium surface and is capable of decontaminating the rough surfaces of the implants. In this report, the use of a combined mechanical and laser therapy was effective in all cases. In clinical controls, the peri-implant mucosa did not show signs of suppuration or bleeding, and the depth on probing was decreased. The bone level was controlled through a cone beam computed tomography and no significant changes were evidenced. At present, the clinical evidence for peri-implant treatment using phototherapy is still limited. However, the laser offers a novel technical approach that is completely different from mechanical instruments and has several beneficial effects, so it can play an important role in the resolution of peri-implantitis.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Lasers Semicondutores/uso terapêutico , Peri-Implantite/radioterapia , Implantes Dentários
9.
Polymers (Basel) ; 12(9)2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32867134

RESUMO

In this work, thermoplastic polyurethane (TPU) composites incorporated with 1.0 wt% Cu particles were synthesized by the melt blending method. The effect of the incorporated copper particle size on the antibacterial, thermal, rheological, and mechanical properties of TPU was investigated. The obtained results showed that (i) the addition of copper particles increased the thermal and mechanical properties because they acted as co-stabilizers of polyurethane (PU) (ii) copper nanoparticles decreased the viscosity of composite melts, and (iii) microparticles > 0.5 µm had a tendency to easily increase the maximum torque and formation of agglomerates. SEM micrographics showed that a good mixture between TPU and copper particles was obtained by the extrusion process. Additionally, copper-TPU composite materials effectively inhibited the growth of the Gram-negative Escherichia coli and the Gram-positive Staphylococcus aureus. Considering that the natural concentration of copper in the blood is in the range of 0.7-0.12 mg/L and that the total migration value of copper particles from TPU was 1000 times lower, the results suggested that TPU nanocomposites could be adequately employed for biomedical applications without a risk of contamination.

11.
Environ Pollut ; 248: 565-573, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30831353

RESUMO

Coastal habitats, in particular sandy beaches, are becoming increasingly exposed to artificial light pollution at night (ALAN). Yet, only a few studies have this far assessed the effects of ALAN on the species inhabiting these ecosystems. In this study we assessed the effects of ALAN on Tylos spinulosus, a prominent wrack-consumer isopod living in sandy beaches of north-central Chile. This species burrows in the sand during daylight and emerges at night to migrate down-shore, so we argue it can be used as a model species for the study of ALAN effects on coastal nocturnal species. We assessed whether ALAN alters the distribution and locomotor activity of this isopod using a light system placed in upper shore sediments close to the edge of the dunes, mimicking light intensities measured near public lighting. The response of the isopods was compared to control transects located farther away and not exposed to artificial light. In parallel, we measured the isopods' locomotor activity in the laboratory using actographs that recorded their movement within mesocosms simulating the beach surface. Measurements in the field indicated a clear reduction in isopod abundance near the source of the light and a restriction of their tidal distribution range, as compared to control transects. Meanwhile, the laboratory experiments showed that in mesocosms exposed to ALAN, isopods exhibited reduced activity and a circadian rhythm that was altered and even lost after a few days. Such changes with respect to control mesocosms with a natural day/night cycle suggest that the changes observed in the field were directly related to a disruption in the locomotor activity of the isopods. All together these results provide causal evidence of negative ALAN effects on this species, and call for further research on other nocturnal sandy beach species that might become increasingly affected by ALAN.


Assuntos
Ritmo Circadiano/efeitos da radiação , Poluição Ambiental/efeitos adversos , Isópodes/fisiologia , Iluminação/efeitos adversos , Locomoção/efeitos da radiação , Animais , Chile , Ecossistema
12.
J Leukoc Biol ; 105(1): 163-175, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30371945

RESUMO

IL-10 is a pleiotropic cytokine with immunoregulatory functions affecting various cell types. In a model of experimental infection with the protozoan Trypanosoma cruzi (T. cruzi), we found increased morbidity and lower parasite control in IL-10 deficient mice (IL-10 KO) compared to wild-type (WT) mice. Despite enhanced Mϕ function and dendritic cell activation, IL-10 KO mice were more susceptible to infection. The kinetics of T cells in spleen and peripheral blood revealed that infected IL-10 KO mice failed to increase the number of spleen and circulating total CD8+ T cells, a phenomenon observed from the second week of infection in WT mice. Total CD8+ T cells from IL-10 KO mice exhibited diminished proliferation, cytotoxic potential and IFN-γ production than their WT counterparts and T. cruzi-specific CD8+ T cells displayed reduced in vivo cytotoxicity. The absence of IL-10 selectively affected expansion, survival, and increased PD-1 expression of CD8+ T cells without altering these same parameters on CD4+ T cells. Increased inhibitory receptors expression and down-modulation of T-bet by CD8+ T cells from IL-10 KO infected mice were compatible with a T cell exhaustion phenotype. Collectively, these findings reveal that during acute infection, IL-10 plays a previously unrecognized stimulatory role on CD8+ T cells, the most relevant lymphocyte population for the control of intracellular T. cruzi stages. A clear knowledge of the underlying mechanisms that drive effector functions of cytotoxic T cells is critical to understand pathogen persistence and rational design of prophylactic strategies against T. cruzi.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Doença de Chagas/imunologia , Doença de Chagas/parasitologia , Interleucina-10/metabolismo , Ativação Linfocitária/imunologia , Trypanosoma cruzi/patogenicidade , Doença Aguda , Animais , Apoptose/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Contagem de Células , Proliferação de Células/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Interleucina-2/biossíntese , Ativação Linfocitária/efeitos dos fármacos , Subpopulações de Linfócitos/imunologia , Camundongos Endogâmicos BALB C , Camundongos Knockout , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Fenótipo , Receptor de Morte Celular Programada 1/metabolismo , Receptores de Interleucina-10/metabolismo , Proteínas Recombinantes/farmacologia , Baço/patologia , Virulência
13.
Int. j. odontostomatol. (Print) ; 12(4): 348-354, dic. 2018. tab
Artigo em Espanhol | LILACS | ID: biblio-975756

RESUMO

RESUMEN: El objetivo del presente trabajo fue estudiar el potencial de los selladores de superficie basados en resinas de evitar cambios de color de resinas compuestas de restauración ante la acción de una bebida coloreada. Para ello, se confeccionó una muestra de 40 discos de resina nanocompuesta Filtek Z350 XT (3M- ESPE) color A2D de 7x2 mm, se pulieron en forma convencional con una serie de discos de óxido de aluminio y se distribuyeron aleatoriamente en 2 grupos de 20 especímenes. Al grupo 1 se le selló toda su superficie usando el agente sellador Fortify®, al grupo 2 se le dejó sin tratar. Se sometió a todos los discos (n=40) a un proceso de termociclado luego del cual se procedió a medir su color inicial mediante el espectrofotómetro de punto Vita Easyshadeµ®. Cada grupo de discos fue inmerso en recipientes metálicos de acero inoxidable en un medio que contenía a una infusión concentrada de té negro durante 7 días a 37 ºC. Finalmente, se midió el color final a cada uno de los grupos de discos luego del periodo de inmersión. Los resultados fueron sometidos al análisis estadístico con el programa Stata 12 y el test T-Student con una significancia de p<0,05. Los resultados indicaron un significativo cambio de color de ambos grupos de discos, siendo ligeramente menor en el grupo de discos sellados, sin embargo, no existió diferencia significativa entre ellos. Como conclusión se determinó que bajo las condiciones del presente estudio el uso del agente sellante de superficie Fortify® no evitó el cambio de color de la resina nanocompuesta de restauración.


ABSTRACT: The objective of the present work was to study the potential of surface sealers based on resins to avoid color changes of resin composite restoration before the action of a colored drink. Therefore, a sample of 40 discs of nanocomposite Filtek Z350 XT (3M-ESPE) color A2D of 7x2 mm was included, these were conventionally polished with a series of aluminum oxide discs and randomly distributed in 2 groups of 20 specimens. Group 1 was sealed with its entire surface using Fortify® sealant, group 2 was left untreated. All discs (n = 40) were subjected to a thermocycling process after which their initial color was measured by the Vita Easyshadem® point spectrophotometer. Each group of discs was immersed in metallic stainless steel containers, in a concentrated infusion of black tea for 7 days at 37 °C. Finally, the final color was measured in each of the disk groups following the immersion period. Results were subjected to the statistical analysis with the Stata 12 program and the T-Student test with a significance of p <0.05. The results indicated a significant color change in both groups of discs, being slightly lower in the group of sealed discs, however, there was no significant difference between them. In conclusion it was determined that under the conditions of the present study the use of the Fortify® surface sealant did not prevent the color change of the nanocomposite restoration resin.


Assuntos
Humanos , Selantes de Fossas e Fissuras/uso terapêutico , Cárie Dentária/prevenção & controle , Resinas Acrílicas/uso terapêutico , Oclusão Dentária , Corantes/efeitos adversos
14.
Artigo em Inglês | MEDLINE | ID: mdl-29888213

RESUMO

Chagas disease is a neglected tropical disease endemic to Latin America, though migratory movements have recently spread it to other regions. Here, we have applied a cascade virtual screening campaign combining ligand- and structure-based methods. In order to find novel inhibitors of putrescine uptake in Trypanosoma cruzi, an ensemble of linear ligand-based classifiers obtained by has been applied as initial screening filter, followed by docking into a homology model of the putrescine permease TcPAT12. 1,000 individual linear classifiers were inferred from a balanced dataset. Subsequently, different schemes were tested to combine the individual classifiers: MIN operator, average ranking, average score, average voting, with MIN operator leading to the best performance. The homology model was based on the arginine/agmatine antiporter (AdiC) from Escherichia coli as template. It showed 64% coverage of the entire query sequence and it was selected based on the normalized Discrete Optimized Protein Energy parameter and the GA341 score. The modeled structure had 96% in the allowed area of Ramachandran's plot, and none of the residues located in non-allowed regions were involved in the active site of the transporter. Positivity Predictive Value surfaces were applied to optimize the score thresholds to be used in the ligand-based virtual screening step: for that purpose Positivity Predictive Value was charted as a function of putative yields of active in the range 0.001-0.010 and the Se/Sp ratio. With a focus on drug repositioning opportunities, DrugBank and Sweetlead databases were subjected to screening. Among 8 hits, cinnarizine, a drug frequently prescribed for motion sickness and balance disorder, was tested against T. cruzi epimastigotes and amastigotes, confirming its trypanocidal effects and its inhibitory effects on putrescine uptake. Furthermore, clofazimine, an antibiotic with already proven trypanocidal effects, also displayed inhibitory effects on putrescine uptake. Two other hits, meclizine and butoconazole, also displayed trypanocidal effects (in the case of meclizine, against both epimastigotes and amastigotes), without inhibiting putrescine uptake.


Assuntos
Transporte Biológico/efeitos dos fármacos , Putrescina/metabolismo , Tripanossomicidas/antagonistas & inibidores , Tripanossomicidas/química , Tripanossomicidas/isolamento & purificação , Doença de Chagas/dietoterapia , Cinarizina/antagonistas & inibidores , Clofazimina/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos/métodos , Reposicionamento de Medicamentos , Imidazóis/antagonistas & inibidores , Meclizina/antagonistas & inibidores , Proteínas de Membrana Transportadoras , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/metabolismo
15.
Rev. salud pública ; Rev. salud pública;19(4): 499-505, jul.-ago. 2017. tab
Artigo em Espanhol | LILACS | ID: biblio-903136

RESUMO

RESUMEN Objetivo Caracterizar y comparar la población de conductores de servicio público de una empresa de transporte en Armenia, Colombia. Materiales y Métodos Estudio analítico de corte transversal en el cual participaron conductores de taxi y colectivo en una empresa de servicio público de Armenia, Colombia. El análisis de las variables se realizó por medio de Statgraphics Centurion XVI. Se de criben las variables, se lleva a cabo una regresión múltiple y una regresión logística. Resultados Participaron 125 conductores, de los cuales, ocho se retiraron y finalmente quedaron 117 de sexo masculino como objeto de investigación. El 28,21 % ha conducido colectivo y 71,79 % taxi. Se observó un mayor consumo de alcohol respecto al de tabaco. El 60,69 % no realizaba ningún tipo de ejercicio físico. El promedio de IMC y perímetro abdominal fue de 28,03 kg/m2 y 100,09 cm, respectivamente. La media de triglicéridos y HDL-c en suero fue de 207,53 mg/dL y 33,12 mg/dL. Del total de conductores, el 49,57 % cumplía con los criterios diagnósticos de METS. Se encontraron diferencias estadísticamente significativas en los valores de IMC, perímetro abdominal, presión arterial sistólica, presión arterial diastólica, ejercicio semanal, triglicéridos y glicemia en ayunas entre individuos con Síndrome Metabólico y sin éste. Conclusiones Los conductores de servicio público presentan un perfil de riesgo aumentado para desarrollar Síndrome Metabólico. La obesidad, la hipertrigliceridemia y los bajos niveles de HDL-c fueron los principales parámetros de alarma para la presencia de Síndrome Metabólico.(AU)


ABSTRACT Objective To characterize and compare the population of public service drivers of a transport company in Armenia, Colombia. Materials and Methods Taxi and bus drivers from a transport company of Armenia, Colombia participated in an Analytical cross-sectional study. The analysis of the variables was made through Statgraphics Centurion XVI. The comparison of variables as well as multiple and logistic regression were carried out. Results 125 individuals participated, 8 were removed, and finally there were 117 male drivers as aim of research. The 28.21 % of individuals have driven small buses and the 71.79 % have driven cars. The increase in alcohol consumption was remarkable compared to tobacco. The 60.69 % of subjects did not get exercise. Besides, the BMI average and abdominal circumference was 28.03 kg/m2 and 100.09 cm respectively. The triglyceride average and serum HDL-C were 207.53 mg/dL to 33.12 mg/dL. 49.57 % of all drivers, fulfilled the Metabolic Syndrome diagnostic criteria. Statistically significant differences were found in the values of BMI, waist circumference, systolic blood pressure, diastolic blood pressure, weekly exercise, triglycerides and fasting glucose between individuals with and without Metabolic Syndrome. Conclusion Public service drivers have a profile risk for developing Metabolic Syndrome. Obesity, hypertriglyceridemia and low HDL-C were the main alarm parameters of the presence of Metabolic.(AU)Syndrome.


Assuntos
Humanos , Condução de Veículo , Síndrome Metabólica/etiologia , Obesidade/epidemiologia , Índice de Massa Corporal , Estudos Transversais/instrumentação , Colômbia/epidemiologia
16.
Rev Salud Publica (Bogota) ; 19(4): 499-505, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-30183854

RESUMO

OBJECTIVE: To characterize and compare the population of public service drivers of a transport company in Armenia, Colombia. MATERIALS AND METHODS: Taxi and bus drivers from a transport company of Armenia, Colombia participated in an Analytical cross-sectional study. The analysis of the variables was made through Statgraphics Centurion XVI. The comparison of variables as well as multiple and logistic regression were carried out. RESULTS: 125 individuals participated, 8 were removed, and finally there were 117 male drivers as aim of research. The 28.21 % of individuals have driven small buses and the 71.79 % have driven cars. The increase in alcohol consumption was remarkable compared to tobacco. The 60.69 % of subjects did not get exercise. Besides, the BMI average and abdominal circumference was 28.03 kg/m2 and 100.09 cm respectively. The triglyceride average and serum HDL-C were 207.53 mg/dL to 33.12 mg/dL. 49.57 % of all drivers, fulfilled the Metabolic Syndrome diagnostic criteria. Statistically significant differences were found in the values of BMI, waist circumference, systolic blood pressure, diastolic blood pressure, weekly exercise, triglycerides and fasting glucose between individuals with and without Metabolic Syndrome. CONCLUSION: Public service drivers have a profile risk for developing Metabolic Syndrome. Obesity, hypertriglyceridemia and low HDL-C were the main alarm parameters of the presence of Metabolic Syndrome.


OBJETIVO: Caracterizar y comparar la población de conductores de servicio público de una empresa de transporte en Armenia, Colombia. MATERIALES Y MÉTODOS: Estudio analítico de corte transversal en el cual participaron conductores de taxi y colectivo en una empresa de servicio público de Armenia, Colombia. El análisis de las variables se realizó por medio de Statgraphics Centurion XVI. Se de criben las variables, se lleva a cabo una regresión múltiple y una regresión logística. RESULTADOS: Participaron 125 conductores, de los cuales, ocho se retiraron y finalmente quedaron 117 de sexo masculino como objeto de investigación. El 28,21 % ha conducido colectivo y 71,79 % taxi. Se observó un mayor consumo de alcohol respecto al de tabaco. El 60,69 % no realizaba ningún tipo de ejercicio físico. El promedio de IMC y perímetro abdominal fue de 28,03 kg/m2 y 100,09 cm, respectivamente. La media de triglicéridos y HDL-c en suero fue de 207,53 mg/dL y 33,12 mg/dL. Del total de conductores, el 49,57 % cumplía con los criterios diagnósticos de METS. Se encontraron diferencias estadísticamente significativas en los valores de IMC, perímetro abdominal, presión arterial sistólica, presión arterial diastólica, ejercicio semanal, triglicéridos y glicemia en ayunas entre individuos con Síndrome Metabólico y sin éste. CONCLUSIONES: Los conductores de servicio público presentan un perfil de riesgo aumentado para desarrollar Síndrome Metabólico. La obesidad, la hipertrigliceridemia y los bajos niveles de HDL-c fueron los principales parámetros de alarma para la presencia de Síndrome Metabólico.


Assuntos
Condução de Veículo , Síndrome Metabólica/epidemiologia , Doenças Profissionais/epidemiologia , Adulto , Colômbia/epidemiologia , Estudos Transversais , Humanos , Modelos Logísticos , Masculino , Síndrome Metabólica/etiologia , Pessoa de Meia-Idade , Veículos Automotores , Doenças Profissionais/etiologia , Fatores de Risco
17.
Artigo em Espanhol | LILACS | ID: biblio-844750

RESUMO

Objetivo: El objetivo de este estudio fue determinar las consecuencias clínicas expresadas en índices COPD y ceod y su relación con la presencia de hipomineralización incisivo molar (HIM) en una población de escolares de 6 a 12 años de la provincia de Santiago. Método: Este estudio de corte transversal fue realizado en 851 escolares de 6 a 12 años de la provincia de Santiago, quienes fueron evaluados por 2 dentistas calibrados. Con consentimiento de los tutores legales, los escolares fueron examinados, y se utilizaron los criterios diagnósticos para HIM de la Academia Europea de Odontopediatría (EAPD). La historia de caries fue determinada con COPD/ceod de acuerdo a los criterios de la OMS. Los datos fueron recolectados en una ficha especialmente diseñada para esto. Los datos fueron analizados con test «t¼ para muestras individuales (considerando p < 0,05). Resultados: Los escolares afectados por HIM tuvieron una media de COPD de 0,91 (±1,21) y una media de ceod de 1,98 (±2,48), el cual fue mayor que el COPD y ceod de escolares sin HIM (0,41 [±0,95] y 1,34 [±2,15] respectivamente). La diferencia entre ambos grupos fue estadísticamente significativa para COPD (p < 0,000) y ceod (p = 0,002). Conclusiones: Escolares de la provincia de Santiago de 6 a 12 años afectados con HIM presentaron mayor COPD/ceod que escolares sin HIM.


Objective. The aim of this study was to determine the clinical consequences, expressed in DMFT and dmft, and their relationship with Molar Incisor Hypomineralisation (MIH) in a population of schoolchildren of 6 to 12 years old in the Santiago Province. Method: A cross-sectional study was conducted on 851 schoolchildren between 6-12 years old from the Santiago Province were examined by two calibrated examiners. With informed consent from their parents, the schoolchildren were examined, and the European Academy of Paediatric Dentistry (EAPD) diagnostic criteria was used for MIH detection. Caries history was assessed with the DMFT/dmft score according to WHO criteria. Data was collected with a form specially designed for this study. Data was analysed using Student's t-test for individual samples and a post-hoc Bonferroni (P < .05). Results: The mean DMFT score in the MIH-affected schoolchildren was 0.91 (±1.21), with a mean dmft score of 1.98 (±2.48), which were greater than the scores in the non-MIH affected schoolchildren (mean DMFT score 0.41 [±0.95] and mean dmft 1.34 [±2.15]). The differences between DMFT and dmft scores in the two groups were statistically significant (P < .000 and P = .002, respectively). Conclusions: Schoolchildren of Santiago Province of 6-12 year old diagnosed with MIH had higher DMFT/dmft scores compared to schoolchildren not affected with MIH.


Assuntos
Humanos , Masculino , Feminino , Criança , Cárie Dentária/epidemiologia , Cárie Dentária/etiologia , Desmineralização do Dente/complicações , Desmineralização do Dente/epidemiologia , Chile , Índice CPO , Doenças Dentárias/epidemiologia , Doenças Dentárias/etiologia
18.
Rev. Fac. Odontol. Univ. Antioq ; 27(2): 425-441, Jan.-July 2016. tab
Artigo em Inglês | LILACS | ID: biblio-957222

RESUMO

ABSTRACT Calcium silicate cements have been used as dental materials for more than twenty years; however, their use in restorative dentistry is more recent. Better mechanical properties and shorter curing times make them suitable for a variety of applications in which they are used as a substitute of dentin, including direct/indirect pulp capping and as cavity base/liner. These materials may also be used to restore enamel temporarily. This article seeks to review the available scientific evidence with a focus on their applications in restorative dentistry. The information was gathered by reviewing original scientific research articles and literature reviews published in journals available in databases such as Medline/Pubmed and Scielo, along with technical information provided by the manufacturers of these cements. This article describes the composition, instructions for use, and curing reaction of calcium silicate cements, as well as the scientific evidence on their applications in restorative dentistry.


RESUMEN Los cementos de silicato de calcio se han aplicado como materiales dentales desde hace más de veinte años; sin embargo, su uso en el área de la odontología restauradora es más reciente. Mejores propiedades mecánicas y menores tiempos de endurecimiento le permiten ser indicados para una variedad de aplicaciones en las que este material se utiliza como sustituto dentinario, entre ellas el recubrimiento pulpar directo/indirecto y como base/liner cavitario. A su vez, también se podría utilizar como material para restaurar esmalte de manera temporal. El presente artículo busca revisar la evidencia científica disponible, enfocándola a sus aplicaciones en odontología restauradora. La información se obtuvo a partir de artículos originales de investigación científica y revisiones de literatura, publicados en revistas disponibles en bases de datos como Medline/Pubmed y Scielo, junto a la información técnica otorgada por los fabricantes de estos cementos. El presente trabajo describe la composición, el modo de empleo, la reacción de fraguado y la evidencia científica sobre las aplicaciones de los cementos de silicato de calcio en odontología restauradora.


Assuntos
Materiais Dentários , Cimentos Dentários , Polpa Dentária
19.
Rev. Fac. Odontol. Univ. Antioq ; 27(1): 177-196, July-Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: biblio-957209

RESUMO

ABSTRACT. Introduction: ameloblasts are cells responsible for the production and mineralization of the organic matrix of enamel through several stages: pre-secretory, secretory, transition, and maturation. The organic matrix components are produced in the secretory phase. In the maturation phase, the organic component is removed and the mineralization process starts. This process requires the involvement of matrix metalloproteinase 20 (MMP-20), also called enamelysin. Several studies have shown the presence of MMP-20 in tooth development and its relationship to alterations in enamel formation. The objective was: to classify the different studies and laboratory techniques used to demonstrate the involvement of enamelysin in tooth development and its relation to pathologies during enamel formation. Methods: a systematic review was conducted with the following bibliographic databases: PubMed, Science-Direct, Hinari, and SciELO, in order to classify the different studies related to the involvement of MMP-20 in tooth development and the methods to detect its expression, between the years of 2009 and 2014. Results and conclusions: 11 in vitro models show that MMP-20 has specific cleavage sites for enamel matrix proteins. This process is altered by chemical composition, ions, and the presence of hydroxyapatite. Enamel morphology is altered in the knockout models. In human studies, MMP-20 has been associated with increased susceptibility to dental caries, enamel thickness, and dental agenesis.


RESUMEN. Introducción: el ameloblasto es la célula encargada de la producción y mineralización de la matriz orgánica del esmalte. Atraviesa varias etapas: la fase pre-secretora, secretora, de transición y maduración. En la fase secretora se producen los componentes de la matriz orgánica. En la fase de maduración se elimina el componente orgánico y se inicia el proceso de mineralización. Este proceso requiere de la participación de la metaloproteinasa de matriz 20 (MMP-20) o también llamada enamelisina. Diversos estudios demuestran la presencia de MMP-20 en el desarrollo dentario y su relación con alteraciones en la formación del esmalte. El objeto fue clasificar los diferentes estudios y técnicas de laboratorio empleadas que demuestren la participación de enamelisina en el desarrollo dentario y su relación con patologías en la formación del esmalte. Métodos: se realizó una revisión sistemática de la literatura con las siguientes bases bibliográficas: PubMed, Science-Direct, Hinari y SciELO, con el fin de clasificar los diferentes estudios relacionados con la participación de MMP-20 en el desarrollo dental y los métodos utilizados para detectar su expresión, entre los años de 2009 a 2014. Resultados y conclusiones: los modelos in vitro evidencian que MMP-20 tiene sitios específicos de escisión para las proteínas de matriz de esmalte. Este proceso se ve alterado por la composición química, iones, y la presencia de hidroxiapatita. En los modelos knockout la morfología del esmalte está alterada. En los estudios en humanos, se ha relacionado la MMP-20 con una mayor susceptibilidad de caries dental, el grosor completo de esmalte y agenesias dentales.


Assuntos
Restauração Dentária Permanente , Resinas Sintéticas , Materiais Dentários
20.
Rev. Fac. Odontol. Univ. Antioq ; 26(2): 358-367, ene.-jun. 2015. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-735127

RESUMO

Introducción: el objetivo de este estudio fue determinar si el entrenamiento, consistente en entrega de contenidos teóricos y el uso de un programa computacional, mejora a corto plazo la discriminación visual de la dimensión más importante en la selección de color dentario: la luminosidad. Métodos: 51 estudiantes que cumplieron con los criterios de inclusión, participaron del estudio firmando un consentimiento informado. Cada uno debió ordenar las 16 muestras de la guía Vitapan Classical, de mayor a menor luminosidad, según escala del fabricante. Este procedimiento se realizó con el código de identificación cubierto, en un tiempo de 3 min, bajo luz día, sobre un fondo de color gris neutro. Se hizo una primera ordenación sin entrenamiento. Posteriormente se realizó el entrenamiento que consistió en una clase teórica de 45 min y práctica durante 1 hora, utilizando los 7 grupos de ejercicios del programa computacional Color training exercises. Finalmente, cada participante hizo una segunda ordenación a la semana siguiente del entrenamiento. Los resultados fueron comparados usando el test T de Student para muestras pareadas. Resultados: en la primera ordenación se obtuvo un porcentaje de aciertos de 33,3% y luego del entrenamiento un promedio de 33,6%. No se observaron diferencias significativas (p = 0,8520). Conclusiones: con las limitaciones propias del estudio, la entrega de contenido teórico más el entrenamiento visual mediante el uso de programa computacional, no es efectivo en mejorar, a corto plazo, la discriminación visual de luminosidad de color dentario en los sujetos en estudio.


Introduction: the objective of this study was to determine whether a short training workshop including theoretical instruction and the use of a computer program improves visual discrimination of the most important dimension in tooth color selection: luminosity. Methods: 51 students who met the inclusion criteria participated in the study after signing an informed consent. Each student was asked to arrange 16 samples of the Vitapan Classical Guide from highest to lowest luminosity according to the manufacturer's scale. This procedure was done in 3 minutes with covered identification codes, under daylight, and against a neutral gray background. This first arrangement was done with no prior instruction. Training was provided afterwards and consisted of a 45-minute theoretical class and one-hour practicum using the 7-exercise groups of the Color Training Exercises computer program. Finally, each participant made a second arrangement one week after the training workshop. The results were compared using the Student T-test for paired samples. Results: the first arrangement yielded 33.3% of success and after training there was 33.6% success in average. There were no significant differences (p = 0.8520). Conclusions: considering the limitations of the study, providing a short theoretical workshop plus visual training using a computer program is not effective in improving visual discrimination of tooth color luminosity in the study subjects.


Assuntos
Cor , Educação em Saúde Bucal , Tutoria
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