Comparación del efecto anticariogénico entre la ovoalbúmina y un barniz fluorurado de aplicación profesional en esmalte y dentina, in situ

68 p.Introducción: Se han reportado agentes de la dieta que poseen propiedades anticariogénicas, constituyendo una posible alternativa como terapia no invasiva. Por ejemplo, un mayor consumo de proteínas se asocia con una menor incidencia de lesiones cariosas. La ovoalbúmina, proteína con potencial anticariogénico, ha demostrado inhibir la desmineralización de esmalte, sin embargo se desconoce la magnitud de tal efecto tanto en esmalte como dentina al ser comparada con el barniz fluorurado. Objetivo: Comparar el efecto anticariogénico de la ovoalbúmina en relación a un barniz fluorurado de aplicación profesional en esmalte y dentina, in situ. Metodología: Se realizó un estudio in situ, ciego, aleatorizado y crossover. Se llevó a cabo tres fases de 14 días cada una, en las cuales 12 voluntarios usaron un aparato palatino con 3 bloques de esmalte y 3 bloques de dentina bovino, con valores de dureza superficial (DS) medidas previamente. Se aplicó en ellos una solución de sacarosa al 20% extraoralmente (8veces/día). Los voluntarios se dividieron en 3 grupos experimentales con su respectivo tratamiento (aplicados 3 veces/día): control (agua destilada), barniz fluorurado 22.600 ppm F (agua destilada) y ovoalbúmina (solución de ovoalbúmina 1mg/mL). En los días 7 (dentina) y 14 (esmalte) de cada fase se recolectaron los bloques evaluando la desmineralización, determinada por el % de pérdida de dureza superficial (%PDS). Resultados: El esmalte expuesto a los tratamientos de barniz y ovoalbúmina obtuvieron una menor %PDS, indicando una reducción de la desmineralización similar (p=0,0001). En dentina el %PDS del grupo ovoalbúmina (p=0,057) fue mayor que el barniz fluorurado (p=0,001) y no difirió del control. Conclusión: La ovoalbúmina en una concentración de 1mg/mL parece tener un efecto anticariogénico sobre la desmineralización del esmalte dentario similar al barniz fluorurado de aplicación profesional. En dentina, este efecto es menos marcado. Palabras claves: Lesión cariosa- Barniz Fluorurado-Dieta –Proteínas de la dieta- Ovoalbúmin

The economic cost of losing native pollinator species for orchard prodution

The alarming loss of pollinator diversity world‐wide can reduce the productivity of pollinator‐dependent crops, which could have economic impacts. However, it is unclear to what extent the loss of a key native pollinator species affects crop production and farmer's profits. By experimentally manipulating the presence of colonies of a native bumblebee species Bombus pauloensis in eight apple orchards in South Argentina, we evaluated the impact of losing natural populations of a key native pollinator group on (a) crop yield, (b) pollination quality, and (c) farmer's profit. To do so, we performed a factorial experiment of pollinator exclusion (yes/no) and hand pollination (yes/no). Our results showed that biotic pollination increased ripe fruit set by 13% when compared to non‐biotic pollination. Additionally, fruit set and the number of fruits per apple tree was reduced by less than a half in those orchards where bumblebees were absent, even when honeybees were present at high densities. Consequently, farmer's profit was 2.4‐fold lower in farms lacking bumblebees than in farms hosting both pollinator species. The pollination experiment further suggested that the benefits of bumblebees could be mediated by improved pollen quality rather than quantity. Synthesis and applications. This study highlights the pervasive consequences of losing key pollinator functional groups, such as bumblebees, for apple production and local economies. Adopting pollinator‐friendly practices such as minimizing the use of synthetic inputs or restoring/maintaining semi‐natural habitats at farm and landscape scales, will have the double advantage of promoting biodiversity conservation, and increasing crop productivity and profitability for local farmers. Yet because the implementation of these practices can take time to deliver results, the management of native pollinator species can be a provisional complementary strategy to increase economic profitability of apple growers in the short term.info:eu-repo/semantics/acceptedVersio

Extractos vegetales con actividad sobre cepas mutadas de saccharomyces cerevisiae con deficiencia en el mecanismo de reparacion del adn

Ciento treinta y ocho extractos obtenidos de plantas pertenecientes a las familias botánicas Asteraceae, Euphorbiaceae, Melastomataceae, Podocarpaceae, Rubiaceae y Solanaceae recolectadas en reservas naturales de la Ecorregión del Eje Cafetero (EEC) fueron evaluadas contra cepas de la levadura Saccharomyces cerevisiae RS 322N, R52Y y RS 321 por el método de difusión en agar, con el propósito de identificar nuevos extractos bioactivos que dañen el ADN y/o que inhiban las topoisomerasas I o II. Los extractos metanólicos de las especies pertenecientes a la familia Solanaceae: Browallia speciosa, Cestrum olivaceum y Solanum brevifolium mostraron selectividad para el ensayo de la levadura Saccharomyces cerevisiae mutada, presentando actividad como inhibidor de la topoisomerasa I. Adicionalmente, el extracto de diclorometano deSolanum deflexiflorum perteneciente a la misma familia presentó actividad inhibidora de la topoisomerasa II

Extractos vegetales con actividad sobre cepas mutadas de saccharomyces cerevisiae con deficiencia en el mecanismo de reparacion del adn

Ciento treinta y ocho extractos obtenidos de plantas pertenecientes a las familias botánicas Asteraceae, Euphorbiaceae, Melastomataceae, Podocarpaceae, Rubiaceae y Solanaceae recolectadas en reservas naturales de la Ecorregión del Eje Cafetero (EEC) fueron evaluadas contra cepas de la levadura Saccharomyces cerevisiae RS 322N, R52Y y RS 321 por el método de difusión en agar, con el propósito de identificar nuevos extractos bioactivos que dañen el ADN y/o que inhiban las topoisomerasas I o II. Los extractos metanólicos de las especies pertenecientes a la familia Solanaceae: Browallia speciosa, Cestrum olivaceum y Solanum brevifolium mostraron selectividad para el ensayo de la levadura Saccharomyces cerevisiae mutada, presentando actividad como inhibidor de la topoisomerasa I. Adicionalmente, el extracto de diclorometano deSolanum deflexiflorum perteneciente a la misma familia presentó actividad inhibidora de la topoisomerasa II

El primer año de la pandemia – ¿Qué hemos aprendido del SARS-CoV-2/COVID-19?

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Infectious Diseases, Social, Economic and Political Crises, Anthropogenic Disasters and Beyond: Venezuela 2019 – Implications for Public Health and Travel Medicine

During last months, there have been a significant increase in the evidences showing the catastrophic health situation in Venezuela. There are multiple epidemics, increase in emerging and reemerging infectious, tropical and parasitic diseases as consequences of the social, economic and political crises, which would be considered today a clearly anthropogenic disaster. Venezuela is facing in 2019, the worse sanitary conditions, with multiple implications for public health and travel medicine. So far, from a global perspective, this situation will be an impediment for the achievement of the sustainable development goals (SDG) in 2030. In this multiauthor review, there is a comprehensive analysis of the situation for infectious diseases, non-communicable diseases, their impact in the Americas region, given the migration crisis as well as the comparative status of the SDG 2030. This discussion can provide input for prioritizing emerging health problems and establish a future agenda

Infectious Diseases, Social, Economic and Political Crises, Anthropogenic Disasters and Beyond: Venezuela 2019 – Implications for Public Health and Travel Medicine

During last months, there have been a significant increase in the evidences showing the catastrophic health situation in Venezuela. There are multiple epidemics, increase in emerging and reemerging infectious, tropical and parasitic diseases as consequences of the social, economic and political crises, which would be considered today a clearly anthropogenic disaster. Venezuela is facing in 2019, the worse sanitary conditions, with multiple implications for public health and travel medicine. So far, from a global perspective, this situation will be an impediment for the achievement of the sustainable development goals (SDG) in 2030. In this multiauthor review, there is a comprehensive analysis of the situation for infectious diseases, non-communicable diseases, their impact in the Americas region, given the migration crisis as well as the comparative status of the SDG 2030. This discussion can provide input for prioritizing emerging health problems and establish a future agenda

The effect of low-level laser irradiation (In-Ga-Al-AsP - 660 nm) on melanoma in vitro and in vivo

<p>Abstract</p> <p>Background</p> <p>It has been speculated that the biostimulatory effect of Low Level Laser Therapy could cause undesirable enhancement of tumor growth in neoplastic diseases. The aim of the present study is to analyze the behavior of melanoma cells (B16F10) <it>in vitro </it>and the <it>in vivo </it>development of melanoma in mice after laser irradiation.</p> <p>Methods</p> <p>We performed a controlled <it>in vitro </it>study on B16F10 melanoma cells to investigate cell viability and cell cycle changes by the Tripan Blue, MTT and cell quest histogram tests at 24, 48 and 72 h post irradiation. The <it>in vivo </it>mouse model (male Balb C, n = 21) of melanoma was used to analyze tumor volume and histological characteristics. Laser irradiation was performed three times (once a day for three consecutive days) with a 660 nm 50 mW CW laser, beam spot size 2 mm², irradiance 2.5 W/cm²and irradiation times of 60s (dose 150 J/cm²) and 420s (dose 1050 J/cm²) respectively.</p> <p>Results</p> <p>There were no statistically significant differences between the <it>in vitro </it>groups, except for an increase in the hypodiploid melanoma cells (8.48 ± 1.40% and 4.26 ± 0.60%) at 72 h post-irradiation. This cancer-protective effect was not reproduced in the <it>in vivo </it>experiment where outcome measures for the 150 J/cm²dose group were not significantly different from controls. For the 1050 J/cm²dose group, there were significant increases in tumor volume, blood vessels and cell abnormalities compared to the other groups.</p> <p>Conclusion</p> <p>LLLT Irradiation should be avoided over melanomas as the combination of high irradiance (2.5 W/cm²) and high dose (1050 J/cm²) significantly increases melanoma tumor growth <it>in vivo</it>.</p

Evaluation of the relationship between academic performance and stress in medical students

Estudiar algunos factores de riesgo que inciden en el rendimiento académico (estrés, alcohol, redes de amistad, depresión y funcionalidad familiar) en los estudiantes de la Facultad de Medicina de la Universidad de Manizales. Materiales y métodos: Estudio descriptivo de una muestra probabilística de estudiantes de 2º a 11º semestre. Se aplicó una encuesta trasversal anónima en donde se establecieron características sociodemográficas, culturales, escolares y motivacionales, así como la presencia de estrés, depresión, disfunción familiar y consumo de sustancias. Se correlacionaron las variables con el rendimiento académico, mediante prueba de chi cuadrado, coeficientes de correlación de Pearson y análisis de regresión lineal. Resultados: Se analizaron 212 estudiantes entre 17 y 31 años, procedentes en su mayoría de otra ciudad. Todas las variables estuvieron asociadas con el rendimiento académico (α ≤ 0.05). Conclusiones: Se encontró relación significativa entre el rendimiento académico y estrés, y de éste con depresión, alcohol y funcionalidad familiar. [Bermúdez SB, Durán MM, Escobar C, Morales A, Monroy SA, Ramírez A, et al. Evaluación de la relación entre rendimiento académico y estrés en estudiantes de MedicinaTo study risk factors that where found as influence in the academic yield (stress, alcohol, friendships, depression and family relations) in the students of the Medicine Faculty of the Universidad de Manizales. Materials and methods: Descriptive study integrated by random selected sample, who were attending of II to XI semester of the Medicine faculty. An anonymous survey was conduced about sociodemographic, cultural, academic and motivational characteris-tics, including stress, depresión, family disfunction and substance abuse. We correlated all variables with academic yield using chi square test, Pearson`s coefficient and lineal regression. Results: 212 students of ages between 17 and 31 years where analyzed, in which the majority where from another city. Some of the factors were detected which affect the academic yield of the students as it is stress, depression, the family function and friendships among others. Conclusions: A significant relation between academic yield and stress was found. In turn, stress variable was influenced by depression, alcohol and family relation. [Bermúdez SB, Durán MM, Escobar C, Morales A, Monroy SA, Ramírez A, et al. Relation between academic yield and stress in medical students