Tension, Free Space, and Cell Damage in a Microfluidic Wound Healing Assay

We use a novel, microfluidics-based technique to deconstruct the classical wound healing scratch assay, decoupling the contribution of free space and cell damage on the migratory dynamics of an epithelial sheet. This method utilizes multiple laminar flows to selectively cleave cells enzymatically, and allows us to present a 'damage free' denudation. We therefore isolate the influence of free space on the onset of sheet migration. First, we observe denudation directly to measure the retraction in the cell sheet that occurs after cell-cell contact is broken, providing direct and quantitative evidence of strong tension within the sheet. We further probe the mechanical integrity of the sheet without denudation, instead using laminar flows to selectively inactivate actomyosin contractility. In both cases, retraction is observed over many cell diameters. We then extend this method and complement the enzymatic denudation with analogies to wounding, including gradients in signals associated with cell damage, such as reactive oxygen species, suspected to play a role in the induction of movement after wounding. These chemical factors are evaluated in combination with the enzymatic cleavage of cells, and are assessed for their influence on the collective migration of a non-abrasively denuded epithelial sheet. We conclude that free space alone is sufficient to induce movement, but this movement is predominantly limited to the leading edge, leaving cells further from the edge less able to move towards the wound. Surprisingly, when coupled with a gradient in ROS to simulate the chemical effects of abrasion however, motility was not restored, but further inhibited.Massachusetts Institute of Technology. Presidential FellowshipNational Institutes of Health (U.S.). Biotechnology Training FellowshipSingapore-MIT Alliance for Research and TechnologyMassachusetts Institute of Biotechnology Training GrantMassachusetts Institute of Technology (Open-source Funding

New microsatellite loci for annatto (Bixa orellana), a source of natural dyes from Brazilian Amazonia

Annatto (Bixa orellana) is a tropical crop native to the Americas with Amazonia as the likely center of origin of domestication. Annatto is important because it produces the dye bixin, which is widely used in the pharmaceutical, food, cosmetic and textile industries. A total of 32 microsatellite loci were isolated from a microsatellite-enriched genomic library, of which 12 polymorphic loci were used to characterize four populations of B. orellana and B. orellana var. urucurana, the wild relative. Higher genetic diversity estimates were detected for the wild populations when compared to the cultivated populations. Also, higher apparent outcrossing rates were found for the two wild than the cultivated populations. These results indicate a mixed mating system for the species. All markers described herein have potential to be used in further studies evaluating the genetic diversity, population dynamics, domestication, breeding, and conservation genetics of annatto. © 2018, Brazilian Society of Plant Breeding. All rights reserved

Letter to the editor: Chemotherapy-induced veno-occlusive disease of the liver

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Percepção de enfermeiros sobre dilemas éticos relacionados a pacientes terminais em Unidades de Terapia Intensiva Percepción de enfermeros sobre dilemas éticos relacionados a pacientes terminales en unidades de terapia intensiva Perception of nurses about ethical dilemmas related to terminal patients in intensive care units

O presente estudo teve por objetivos conhecer a percepção de enfermeiros sobre dilemas éticos existentes na assistência de enfermagem a pacientes terminais, no contexto da UTI de um hospital geral do município de São Paulo e o que é considerado para a tomada de decisão. O estudo foi realizado através de entrevistas com dez enfermeiros atuantes na UTI, utilizando uma abordagem qualitativa, conforme a análise de conteúdo. Foram encontrados dilemas éticos ligados a: diversidade de valores; presença dos pacientes terminais na UTI; incertezas sobre a terminalidade e limites de intervenção para prolongar a vida dos pacientes; discordância de tomadas de decisão; não aceitação do processo de morte pela família do paciente e a falta de esclarecimento da família e do paciente. Além disso, para tomar decisão frente aos dilemas éticos, ele considera os seus valores, a ética profissional, a empatia e o diálogo com os colegas.<br>El presente estudio tuvo como objetivos conocer la percepción de enfermeros sobre dilemas éticos existentes en la asistencia de enfermería a pacientes terminales en el contexto de la UTI de un hospital de São Paulo y lo que se considera como la toma de decisiones. El estudio fue realizado desde una perspectiva cualitativa, utilizando el análisis de contenidos. Fueron entrevistados diez enfermeros actuantes en la UTI. El estudio mostró que los enfermeros encuentran dilemas éticos generados por diversos factores: diversidad de valores; presencia dem los pacientes terminales en la UTI; incertidumbre generada a raíz de la condición terminal; los límites de intervención para prolongar la vida; discordancia en la toma de decisiones; resistencia para aceptar el proceso de muerte por parte de la familia y la falta de esclarecimiento de la família y de los pacientes. Además, sus valores, la ética profesional, la empatía y el diálogo son tenidos en cuenta para tomar decisiones.<br>The purpose of this study was to learn about nurses' perception about ethical dilemmas in nursing care for terminal patients in the context of a general hospital ICU in the city of São Paulo, and what they take into account when making decisions. The study was performed through interviews with ten nurses working at the ICU, using a qualitative approach based on content analysis. Ethical dilemmas were found to be linked to: diversity of values; presence of terminal patients at the ICU; uncertainties about terminality and the limits of intervention to prolong the patients' lives; disagreements in decision-making; non-acceptance of the process of dying by the patients' families and the lack of clarifications for the patient and the family. In addition, the nurses consider their values, the professional ethics, empathy and dialogue with co-workers to make decisions in view of such ethical dilemmas

Evolução de homicídios por área geográfica em Pernambuco entre 1980 e 1998 Homicide progression per geographical area in the State of Pernambuco, Brazil, 1980-1998

OBJETIVO: Analisar magnitude e evolução temporal de homicídios na população masculina, segundo divisão geopolítica. MÉTODOS: Foi realizado estudo do tipo ecológico, no qual se efetuou uma análise de série temporal utilizando-se as técnicas de média móvel e análise de regressão. Foi estudada a população masculina de 15 a 49 anos de idade, residente no estado de Pernambuco, Brasil. A fonte de dados utilizada para os óbitos foi o Sistema de Informação em Mortalidade do Ministério da Saúde. Para a população, foram usados os dados dos censos de 1980, 1991 e a contagem populacional de 1996 da Fundação Instituto Brasileiro de Geografia e Estatística. Para os anos intercensitários, as populações foram estimadas por interpolação e, para os anos de 1997 e 1998, por projeção, usando-se o método geométrico. RESULTADOS: Na década de 1980, houve crescimento mais elevado (390%) nas taxas de homicídios em Recife, capital do estado de Pernambuco. Na década de 90, o maior crescimento ocorreu na região metropolitana (68,5%), sugerindo disseminação da violência da capital em direção aos demais municípios da grande Recife. A tendência das taxas de homicídios apresentou comportamento de crescimento linear no interior do estado. Já na capital e região metropolitana, esse comportamento caracterizou-se por um crescimento exponencial. O percentual de homicídios por arma de fogo a partir de 1984 apresentou-se acima de 50% nas três áreas estudadas. CONCLUSÕES: A evolução dos homicídios nas três áreas estudadas revela um crescimento diferenciado e ressalta que embora seja o mesmo fenômeno -- homicídio masculino --, as dinâmicas geradoras desse processo possuem especificidades entre esses espaços mais urbanos e o interior que devem ser levadas em consideração no desenvolvimento de políticas públicas regionalizadas de assistência às vítimas e de prevenção desses eventos.<br>OBJECTIVE: To analyze the magnitude and growth of homicides among male population according to the geopolitical areas. METHODS: An ecological study including a time series analysis was carried out among 15 to 49 year-old males living in the state of Pernambuco, Brazil. Mortality data was collected from the Ministry of Health's Mortality Information System. Data on population was from the 1980 and 1991 censuses and the 1996 Brazilian Institute of Geography and Statistics' census. For inter-census years, the population size was estimated by interpolation, and for the period 1997-1998 it was estimated by projection, using the geometric method. Statistical analysis was performed using mobile mean and regression analysis techniques. RESULTS: In the 1980s, the greatest increase in homicide rates was in the state capital (390%). In the 1990s, the greatest increase occurred in the metropolitan region (68.5%) suggesting violence spread from the capital to other municipalities of greater Recife. Homicide rates tended to grow linearly in the interior, whilst there was an exponential growth in the capital and metropolitan region. A striking feature is the high rates of homicides with firearms in the three areas. CONCLUSIONS: The progression of homicides in the three areas of study shows a characteristic increase. It should be stressed that even though it is the same phenomenon - male homicides -, the generating dynamic of this process has geographical particularities between more urban and interior areas and they should be taken into account while developing local policies for supporting victims and preventing these events

Relationship between fruit traits and contents of ascorbic acid and carotenoids in peach

This study aimed to evaluate the relationship between fruit traits and their direct and indirect effects on the content of ascorbic acid and carotenoids in peaches and nectarines. The traits fruit mass (FM); equatorial diameter (ED); suture diameter (SD); polar diameter (PD); pulp firmness (FIR); soluble solids (SS); titratable acidity (TA); SS/TA ratio; contents of ascorbic acid (AA) and carotenoids (CT); and skin and pulp color were evaluated in 28 peach cultivars, and two nectarine cultivars. The phenotypic correlation coefficients were estimated (rf), and after multicollinearity diagnosis, unfolding was carried out in direct and indirect effects of the explanatory variables in the response variable by using path analysis. The strongest correlations were found between ​​ FM, SD, ED, and PD, and between carotenoid content and °h pulp. The traits considered in the path diagrams are not the main determinants of the ascorbic acid content. The yellow color of the pulp has the potential for indirect selection for carotenoid content