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1.
J Esthet Restor Dent ; 35(2): 416-422, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36200919

RESUMEN

OBJECTIVE: To evaluate if distinct 20%-22% carbamide peroxide bleaching gels present similar decomposition pattern and pH during the clinical use in both arches, as well as gels viscosity. METHODS: Participants randomly received treatments with carbamide peroxide gels (n = 10): OPF (OpalescencePF-20%); PNT (Polanight-22%); and WPC (Whiteness Perfect-22%) in three different days, with 2-day washout. Decomposition pattern was assessed by peroxide concentration. Both PC and pH of bleaching gels were measured in different time points in upper and lower trays during a total of 120 min of clinical use. Viscosity of bleaching gels was measured in triplicate. ANOVA and Tukey's test were applied (α = 0.05). RESULTS: Regarding decomposition pattern, no significant differences were observed for the interaction between gel, time, and tray position factors. The peroxide concentration progressively reduced until 120 min of trays use (p < 0.001), being overall more notable in lower trays (p < 0.001). Regarding pH, the lowest values were verified in WPC within time. At 120 min, an increase of pH was observed for both WPC and OPF (p < 0.001) compared to baseline means. PNT exhibited constant pH values over time. The values of viscosity were: OPF (1.682.000 ± 19 cP)a, WPC (1.388.667 ± 172.63 cP)ab, PNT (579.567 ± 0.98 cP)b. CONCLUSIONS: The bleaching gels presented overall decomposition pattern clinically equivalent, being more notable in lower trays over time. Nevertheless, distinct pH and viscosities were observed among the products. CLINICAL SIGNIFICANCE: Although the manufacturers recommend different times of use for bleaching gels with similar peroxide concentrations, the commercial products tested did not exhibit clinically relevant difference in the decomposition pattern during the 120 min of clinical procedure.


Asunto(s)
Blanqueadores Dentales , Blanqueamiento de Dientes , Humanos , Peróxido de Carbamida , Geles , Peróxido de Hidrógeno , Peróxidos/química , Blanqueamiento de Dientes/métodos , Blanqueadores Dentales/química , Urea/química , Estudios Cruzados
2.
Neotrop Entomol ; 51(3): 474-482, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35575878

RESUMEN

Musca domestica L. is a cosmopolitan nuisance of high sanitary importance. Entomopathogenic fungi are innovative and attractive tools for integrated control of the housefly to overcome insufficient levels of control caused by increasing resistance of this pest against chemical insecticides. High virulence of a fungal strain is a prerequisite to develop a mycoinsecticide, and the present study investigated the potential of hypocrealean fungi from the genera Beauveria, Clonostachys, Cordyceps, Akanthomyces, Metarhizium, and Tolypocladium, isolated from mosquitoes in Central Brazil against M. domestica. The highest mortalities (larvae, pupae, and adults) were caused by Metarhizium humberi IP 478 (98%) and IP 421 (90%), Metarhizium anisopliae IP 432 (85%), Beauveria bassiana IP 433 (82%), and Tolypocladium cylindrosporum IP 425 (68%) after a 23-day exposure of initially pre-pupating third instar larvae to conidia mixed with vermiculite. Lethal concentrations to kill 90% of adults of IP 433 and IP 478 were 5 × 107 and 108 conidia g-1 substrate, respectively. Fifty percent of adults were killed within 4 to 5 days of exposure initially as pupae close to emergence to substrate treated with conidia of IP 478 or IP 433 at 1.1 × 108 conidia g-1, respectively. The other fungal strains tested were less virulent. The results demonstrate high potentials for conidial preparations in vermiculite of IP 433 and IP 478 as candidates for the biological control of both pre-pupating larvae, pupae, and emerging adults of houseflies.


Asunto(s)
Beauveria , Moscas Domésticas , Metarhizium , Silicatos de Aluminio , Animales , Brasil , Larva/microbiología , Control Biológico de Vectores , Esporas Fúngicas
3.
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1410755

RESUMEN

O Ensino Remoto Emergencial (ERE) foi adotado por algumas instituições de ensino durante a pandemia da covid-19. Objetivou-se analisar a percepção de concluintes do curso de Licenciatura em Educação Física (EF) sobre o ERE. As participantes relataram ter bom ambiente para acompanhar as aulas remotas, não pensaram em trancar a matrícula/desistir do curso, mas se sentiram tristes por terem concluído pelo ERE. Foi detectada redução do interesse pelas aulas remotas e percepção que o ERE prejudicou a formação docente, além da falta de interação, distanciamento das aulas práticas e não poder estar presencialmente na escola nos estágios. A maior flexibilização de horário foi o aspecto positivo indicado.


Emergency Remote Learning (ERE) was adopted by some educational institutions during the pandemic of COVID-19. We aimed to analyze the perception of graduates of the Physical Education (PE) degree course about the ERE. The participants reported having a good environment to follow the remote classes, did not think about locking the enrollment/dropping out of the course, and felt sad to have concluded by the ERE. A reduction in interest in remote classes and the perception that the distance learning program had detrimental effects on teacher education were indicated, as well as a lack of interaction, distance from practical classes, and not being able to be present in the school during internships. The positive aspect indicated was a more flexible schedule.


El aprendizaje a distancia de emergencia (ERE) fue adoptado por algunas instituciones educativas durante la pandemia de COVID-19. El objetivo de este estudio fue analizar la percepción de los egresados de la carrera de Educación Física (EF) sobre el ERE. Los participantes manifestaron tener un buen ambiente para seguir las clases a distancia, no pensaron en cerrar la matrícula/abandonar el curso y se sintieron tristes por haber concluido por el ERE. Se indicó una reducción del interés por las clases a distancia y la percepción de que la ED había perjudicado su formación docente, así como la falta de interacción, el alejamiento de las clases prácticas y el no poder estar presente en la escuela durante las prácticas. La mayor flexibilidad de horarios fue el aspecto positivo indicado.

4.
Sci Total Environ ; 759: 143456, 2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33218813

RESUMEN

Iron ore tailings (IOT) represent a major problem in the mining industry worldwide due to large volumes of waste disposed in mine sites. IOT are exposed to the environment and subjected to wind and water dispersion, even under non-catastrophic scenarios as dam collapses, and the effects of these particles to the biota are still mostly unknown. This work aimed to prepare and to characterize a suspension containing the finest (micro/nano range) particles of IOT and to evaluate its effects on development and behavior of zebrafish (Danio rerio), at both embryonic and larval stages. IOT suspension comprised 37 mg L-1 of a multi-mineral material mainly composed by hematite and quartz, in a size-range of 33-1400 nm. Regarding in vivo toxicological assays, no robust alterations were recorded in functional, morphological and behavioral end-points analyzed, although a significant adhesion of IOT particles on zebrafish chorion was observed, without a prejudice of embryo hatching. Under applied conditions, iron ore particles did not present harmful effects to the initial stages of zebrafish development, and the particle size range and potential interactions with SiO2 content might be behind such effect.


Asunto(s)
Nanopartículas , Pez Cebra , Animales , Embrión no Mamífero , Hierro , Larva , Dióxido de Silicio
6.
Food Funct ; 11(6): 5346-5356, 2020 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-32462155

RESUMEN

Twenty-nine flavonoid glycosides were identified in the aqueous extract (PC) of Petroselinum crispum var. crispum leaves and apiin, the major compound, was isolated thereof. Apigenin was obtained (90% purity) by the hydrolysis of apiin. A high content of phenolics (12.49 ± 1.70 mg GAE per g of parsley extract - Folin-Ciocalteu method) and total flavonoids (15.05 ± 2.20 mg of quercetin equivalents per g of parsley extract - aluminum chloride method) was quantified in P. crispum, as well as high antioxidant activity ((EC50 - 15.50 mg mL-1, DPPH method) and (189.8 mM Fe(ii) per mg of dry plant aqueous extract - FRAP method)). In vivo analysis with Saccharomyces cerevisiae cells showed low toxicity of the aqueous extract of parsley, however, it revealed a high dose-dependent antioxidant potential, mainly in the lipoperoxidation assay. In addition, flavonoid apiin also showed antioxidant action on yeast cells under oxidative stress in the cell viability assay (0.1 mM) and lipid peroxidation (0.01 and 0.1 mM), while apigenin was slightly antioxidant. Therefore, it is likely that the antioxidant activity of apiin is related to the total antioxidant capacity of parsley.


Asunto(s)
Antioxidantes/análisis , Petroselinum/química , Extractos Vegetales/análisis , Extractos Vegetales/aislamiento & purificación , Antioxidantes/farmacología , Apigenina/análisis , Apigenina/farmacología , Flavonoides/análisis , Glicósidos/análisis , Estrés Oxidativo , Fenoles/análisis , Extractos Vegetales/farmacología , Hojas de la Planta/química , Saccharomyces cerevisiae/efectos de los fármacos
7.
Chemosphere ; 253: 126665, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32278191

RESUMEN

Acid mine drainage (AMD) represents a major problem in the mining industry worldwide due to the risk of water and soil pollution. Its active treatment involves the addition of alkaline reagents such as NaOH or Ca(OH)2 to increase the pH and precipitate the dissolved metals, although substantial amounts of dissolved ions might persists. Under a remediation approach, the aim of this work was to assess the chemical and physical characteristics of treated effluent and to evaluate its ecotoxicological effects on zebrafish (Danio rerio) embryonic and larval stages, through developmental, functional, morphological, and behavioral end-points. The studied AMD sample, highly associated with pyrite, presented high sulfate and dissolved metal ions content and was submitted to the following treatment conditions: NaOH - pH 7.0 and 8.7, and Ca(OH)2 - pH 7.0 and 8.7. All neutralizing treatments resulted in a satisfactory reduction of the metals concentration, with best results achieved using Ca(OH)2 at pH 8.7; although Mn and As still remained above or very near the discharge maximum limits according to Brazilian legislation. Therefore, an additional step was employed to Mn and As adsorption by algal biomass. Regarding in-vivo toxicological assays, no significant lethality was recorded in all treated AMD groups, although adverse effects were observed in all endpoints analyzed. Ca(OH)2 groups performed closer to control than NaOH-treated groups. The additional polishing stage treatment with the algae Scenesmus sp. allowed tenuous improvements in terms of removal of residual amounts of As and Mn but not in the toxicological characteristics of treated AMD.


Asunto(s)
Minería , Contaminantes Químicos del Agua/química , Ácidos/química , Adsorción , Animales , Brasil , Ecotoxicología , Concentración de Iones de Hidrógeno , Hierro , Metales/análisis , Sulfatos , Sulfuros , Agua , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Pez Cebra/fisiología
8.
Rev Panam Salud Publica ; 43: e96, 2019.
Artículo en Portugués | MEDLINE | ID: mdl-31819746

RESUMEN

The present report describes the process of convergence between the Brazilian National School Feeding Program (PNAE) and the Brazilian National Textbook Program (PNLD), highlighting a project that introduced diet and nutrition topics on the covers of textbooks distributed at no cost to all public schools in Brazil. This intersectoral initiative speaks directly to the recommendations of the Dietary Guidelines for the Brazilian Population, the principles of the Nutrition Education Framework for Public Policies, and the proposals laid out in the United Nations Decade of Action on Nutrition. The report shows that the construction of a dialogic and intersectoral space is a possible path to promote a healthy and appropriate diet among students. However, further studies are necessary to evaluate the effectiveness of introducing diet and nutrition topics in textbooks, and also studies investigating the perception of teachers and students regarding the use of books to promote education on diet and nutrition.


El objetivo del presente informe es describir la trayectoria de convergencia del Programa Nacional de Alimentación Escolar (PNAE) con el Programa Nacional de Libros y Materiales Didácticos (PNLD) en Brasil, con hincapié en el proyecto de inclusión de los temas de alimentación y nutrición en las portadas de los libros didácticos distribuidos de manera general y gratuita a todas las escuelas públicas brasileñas. Esa iniciativa intersectorial guarda una relación directa con las recomendaciones de la guía alimentaria para la población brasileña, los principios del marco de educación alimentaria y nutricional para las políticas públicas y las propuestas del Decenio de las Naciones Unidas de Acción sobre la Nutrición. Se comprobó que la construcción de un espacio dialógico e intersectorial es una posible vía para fomentar el consumo de una alimentación adecuada y saludable en los estudiantes. Sin embargo, se recomienda realizar estudios para evaluar la efectividad de la inclusión de los temas de alimentación y nutrición en los libros didácticos e investigar la forma en que el cuerpo docente y discente percibe el empleo de los libros para promover la educación alimentaria y nutricional.

9.
Psicol Reflex Crit ; 32(1): 20, 2019 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-32026072

RESUMEN

Peers are the preferred source of help for Brazilian adolescents who experience dating violence. However, they are not always the best informants for effective responses for dealing with situations of violence in romantic relationships among peers. This experimental study aimed to evaluate the short-term efficacy of three aspects of a peer- and bystander approach-based intervention: the intent to offer help, empathy, and bystander attitudes in response to dating violence in a Brazilian sample of adolescents. The study's participants were 33 adolescents randomized in two groups: experimental group (EG, n = 14) and control group (CG, n = 19). The EG underwent three weekly intervention sessions of 90 min each on the healthy versus violent romantic relationships, the quality of friendship in the peer network, and the role of the bystander, while the CG received no intervention. Evaluations were performed 1 week before and two and half months after the intervention. Statistically significant differences between EG and CG at post-test were not found in intention to help, empathy, and bystander attitudes. Future studies should include evaluations of larger samples and mid- and long-term follow-ups to identify patterns of change over the long term as well as examine barriers to utilization of bystander behaviors by adolescents in Brazilian culture.

10.
Int J Dent ; 2017: 5815493, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28638410

RESUMEN

AIM: To assess the epidemiological and clinical factors that influence the prognosis of oral and oropharyngeal squamous cell carcinoma (SCC). METHODS: One hundred and twenty-one cases of oral and oropharyngeal SCC were selected. The survival curves for each variable were estimated using the Kaplan-Meier method. The Cox regression model was applied to assess the effect of the variables on survival. RESULTS: Cancers at an advanced stage were observed in 103 patients (85.1%). Cancers on the tongue were more frequent (23.1%). The survival analysis was 59.9% in one year, 40.7% in two years, and 27.8% in 5 years. There was a significant low survival rate linked to alcohol intake (p = 0.038), advanced cancer staging (p = 0.003), and procedures without surgery (p < 0.001). When these variables were included in the Cox regression model only surgery procedures (p = 0.005) demonstrated a significant effect on survival. CONCLUSION: The findings suggest that patients who underwent surgery had a greater survival rate compared with those that did not. The low survival rates and the high percentage of patients diagnosed at advanced stages demonstrate that oral and oropharyngeal cancer patients should receive more attention.

11.
J Invertebr Pathol ; 136: 109-16, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27018147

RESUMEN

Numerous isolates of an oomycete 'fungus', Leptolegnia chapmanii, are reported from Brazil for the first time. This aquatic pathogen was baited with Aedes aegypti sentinel larvae from stagnant, temporary bodies of water in selected locations under secondary tropical forest in and near the central Brazilian city of Goiânia and from more distant sites in the western and northern regions of the state of Goiás. Isolates were identified based on their morphological and developmental characters, comparative sequence data for the ITS and TEF loci, as well as their rapid activity against A. aegypti larvae. Taxonomic issues affecting the application of the name L. chapmanii and its typification are rectified. This study contributes to a better understanding of the presence and distribution of this oomycete in Brazil, its sequence-based identification, and of its potential as a biological agent against mosquito vectors.


Asunto(s)
Aedes/microbiología , Peronospora/clasificación , Animales , Brasil , Reacción en Cadena de la Polimerasa
12.
Rev Saude Publica ; 50 Suppl 1: 15s, 2016 Feb.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-26910547

RESUMEN

OBJECTIVE To estimate the prevalence of sexual initiation and contraceptive use at the last sexual intercourse of Brazilian adolescents, according to sociodemographic features. METHODS The data were obtained from the Study of Cardiovascular Risks in Adolescents (ERICA), a national school-based cross-sectional study. We included 74,589 adolescents from 32 geographic strata (27 capitals and five sets of municipalities with more than 100,000 inhabitants of each of the five macro-regions of the Country). Information on sexual initiation and contraceptive use at the last sexual intercourse (male condom and oral contraceptive pill) has been used. We have estimated prevalence and confidence intervals (95%CI) considering sample weights according to sex, age, type of school, residence status, macro-region and capitals. RESULTS We observed that 28.1% (95%CI 27.0-29.2) of the adolescents had already initiated sexual life, with higher prevalence among those aged 17 years (56.4%, 95%CI 53.9-58.9), males (33.5%, 95%CI 31.8-35.2), studying at public schools (29.9%, 95%CI 28.5-31.4), and from the Northern region (33.9%, 95%CI 32.3-35.4), mainly from Macapa, Manaus, and Rio Branco. Among those who had started their sexual life, 82.3% (95%CI 81.1-83.4) reported the use of contraceptive methods at the last intercourse, and the prevalence of use was higher among adolescents aged 17 years (85.3%, 95%CI 82.7-87.6), females (85.2%, 95%CI 83.8-86.5) and those living in the Southern region (85.9%, 95%CI 82.9-88.5). Male condom was used by 68.8% (95%CI 66.9-70.7), with no difference by type of school or macro-regions; the contraceptive pill was used by 13.4% (CI95% 12.2-14.6), and more frequently used among women (24.7%, 95%CI 22.5-27,0) and 17-year-old adolescents (20.8%, 95%CI 18.2-23.6) from urban settings(13.7%, 95%CI 12.5-14.9) and from the Southern region (22.6%, 95%CI 19.0-26.8), and less often in the Northern region. CONCLUSIONS ERICA's data analysis on sexuality and contraception shows heterogeneities in the prevalence of sexual initiation and use of contraceptive methods among Brazilian adolescents, depending on their age, where they live, and the type of school they study at. Younger adolescents and those living in the Northern region seem to be more vulnerable to the consequences of unprotected sexual intercourses.


Asunto(s)
Conducta Sexual/estadística & datos numéricos , Adolescente , Conducta del Adolescente/fisiología , Brasil , Condones/estadística & datos numéricos , Anticoncepción , Conducta Anticonceptiva , Estudios Transversales , Femenino , Humanos , Masculino , Características de la Residencia , Encuestas y Cuestionarios
13.
Nat Struct Mol Biol ; 22(2): 138-44, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25599396

RESUMEN

Aquarius is a multifunctional putative RNA helicase that binds precursor-mRNA introns at a defined position. Here we report the crystal structure of human Aquarius, revealing a central RNA helicase core and several unique accessory domains, including an ARM-repeat domain. We show that Aquarius is integrated into spliceosomes as part of a pentameric intron-binding complex (IBC) that, together with the ARM domain, cross-links to U2 snRNP proteins within activated spliceosomes; this suggests that the latter aid in positioning Aquarius on the intron. Aquarius's ARM domain is essential for IBC formation, thus indicating that it has a key protein-protein-scaffolding role. Finally, we provide evidence that Aquarius is required for efficient precursor-mRNA splicing in vitro. Our findings highlight the remarkable structural adaptations of a helicase to achieve position-specific recruitment to a ribonucleoprotein complex and reveal a new building block of the human spliceosome.


Asunto(s)
ARN Helicasas/química , ARN Helicasas/metabolismo , Empalmosomas/metabolismo , Adenilil Imidodifosfato/química , Adenilil Imidodifosfato/metabolismo , Cristalografía por Rayos X , Humanos , Intrones/genética , Unión Proteica/genética , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , ARN Helicasas/genética , Empalme del ARN/genética , Ribonucleoproteína Nuclear Pequeña U2/química , Ribonucleoproteína Nuclear Pequeña U2/metabolismo
14.
J Exp Bot ; 57(1): 91-9, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16291801

RESUMEN

The functional role of Adh in regulating susceptibility to abiotic stress and the synthesis of secondary metabolites was investigated in transgenic grapevine plants over- and underexpressing alcohol dehydrogenase (Adh). Plants were transformed with gene constructs containing a sense or antisense orientated grapevine VvAdh2 cDNA under the constitutive cauliflower mosaic virus 35S promoter. Plants transformed with either antisense orientation or the Adh-less construct displayed a low but detectable constitutive ADH activity, whereas plants transformed with the sense-expressed transgene showed a significantly higher (100-fold) ADH activity than the control. Compared with the control, the sense transgene induced an overexpression of VvAdh2 transcripts, whereas a reduced VvAdh2 expression was detected in antisense transformants. Grapevine plants overexpressing Adh displayed a lower sucrose content, a higher degree of polymerization of proanthocyanidins, and a generally increased content of volatile compounds, mainly in carotenoid- and shikimate-derived volatiles. In general, no significant differences between sense/antisense transformants were observed with regard to carotenoid and chlorophyll contents, suggesting a strong metabolic regulation of the synthesis of these compounds.


Asunto(s)
Alcohol Deshidrogenasa/metabolismo , Hojas de la Planta/enzimología , Vitis/enzimología , Alcohol Deshidrogenasa/genética , Carotenoides/metabolismo , Clorofila/metabolismo , Ácidos Cumáricos/metabolismo , Flavonoles/metabolismo , Hexosas/metabolismo , Norisoprenoides/metabolismo , Plantas Modificadas Genéticamente , Proantocianidinas/metabolismo , Terpenos/metabolismo , Transformación Genética , Vitis/genética
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