Influence of surface geometry on the culture of human cell lines: a comparative study using flat, round-bottom and v-shaped 96 well plates

© 2017 Shafaie et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.In vitro cell based models have been invaluable tools for studying cell behaviour and for investigating drug disposition, toxicity and potential adverse effects of administered drugs. Within this drug discovery pipeline, the ability to assess and prioritise candidate compounds as soon as possible offers a distinct advantage. However, the ability to apply this approach to a cell culture study is limited by the need to provide an accurate, in vitro-like, microenvironment in conjunction with a low cost and high-throughput screening (HTS) methodology. Although the geometry and/or alignment of cells has been reported to have a profound influence on cell growth and differentiation, only a handful of studies have directly compared the growth of a single cell line on different shaped multiwell plates the most commonly used substrate for HTS, in vitro, studies. Herein, the impact of various surface geometries (flat, round and v-shaped 96 well plates), as well as fixed volume growth media and fixed growth surface area have been investigated on the characteristics of three commonly used human cell lines in biopharmaceutical research and development, namely ARPE-19 (retinal epithelial), A549 (alveolar epithelial) and Malme-3M (dermal fibroblastic) cells. The effect of the surface curvature on cells was characterised using a combination of a metabolic activity assay (CellTiter AQ/MTS), LDH release profiles (CytoTox ONE) and absolute cell counts (Guava ViaCount), respectively. In addition, cell differentiation and expression of specific marker proteins were determined using flow cytometry. These in vitro results confirmed that surface topography had a significant effect (p < 0.05) on cell activity and morphology. However, although specific marker proteins were expressed on day 1 and 5 of the experiment, no significant differences were seen between the different plate geometries (p < 0.05) at the later time point. Accordingly, these results highlight the impact of substrate geometry on the culture of a cell line and the influence it has on the cells' correct growth and differentiation characteristics. As such, these results provide important implications in many aspects of cell biology the development of a HTS, in vitro, cell based systems to further investigate different aspects of toxicity testing and drug delivery.Peer reviewedFinal Published versio

Interferometric Observations of Rapidly Rotating Stars

Optical interferometry provides us with a unique opportunity to improve our understanding of stellar structure and evolution. Through direct observation of rotationally distorted photospheres at sub-milliarcsecond scales, we are now able to characterize latitude dependencies of stellar radius, temperature structure, and even energy transport. These detailed new views of stars are leading to revised thinking in a broad array of associated topics, such as spectroscopy, stellar evolution, and exoplanet detection. As newly advanced techniques and instrumentation mature, this topic in astronomy is poised to greatly expand in depth and influence.Comment: Accepted for publication in A&AR

Mortalidade infantil no Estado de São Paulo, 1999: uma análise das causas múltiplas de morte a partir de componentes principais Infant mortality in the State of São Paulo, 1999: principal components analysis of multiple causes of death

OBJETIVOS: Descrever o padrão da mortalidade infantil no Estado de São Paulo em 1999, segundo causas múltiplas de morte, bem como comparar os dados de causas básicas e múltiplas de óbito. MATERIAL E MÉTODOS: Utilizou-se dados de 12.793 óbitos infantis para 1999, obtidos da Fundação Sistema Estadual de Análise de Dados (Seade). As causas de óbito haviam sido codificadas de acordo com a Décima Classificação Internacional de Doenças e foram categorizadas em 28 grupos de causas. Para análise das causas múltiplas de morte, fez-se uma tabulação simples das mesmas e utilizou-se a análise de componentes principais, a fim de se obter os principais grupos de enfermidades que conduziram ao óbito. RESULTADOS: As principais causas múltiplas de óbito foram os transtornos respiratórios e cardiovasculares específicos do período perinatal (24,2% do total de causas múltiplas), os transtornos relacionados com a duração da gestação e com o crescimento fetal (20,2%), as malformações congênitas (8,6%) e as infecções perinatais (7,6%). A análise de componentes principais revelou três componentes interpretáveis, relativos aos óbitos devidos a causas de origem "pós-neonatais, infecciosas, redutíveis", às "complicações de procedimentos e causas externas" e aos "transtornos perinatais não associados ao baixo peso e/ou à imaturidade". CONCLUSÃO: A sistematização das causas múltiplas de morte em conjuntos de enfermidades permitiu analisá-las e entender como se associavam, desdobrando-se em manifestações de doenças que conduziram à morte, o que não é possível através da análise segundo causas básicas. Foi possível, então, observar com maior clareza os conjuntos de enfermidades que levaram ao óbito, o que é mais elucidativo para fins de Saúde Pública, visando a prevenção das doenças em suas diversas fases de causação.<br>OBJECTIVE: To describe infant mortality in the State of São Paulo, in 1999, based on multiple causes of death and to compare data from underlying and multiple causes of death. METHODS: Data came from 12,793 infant death records in 1999, of Seade Foundation (State Data Analysis System Foundation). Causes of death were coded according to the Tenth Revision of the International Statistical Classification of Diseases and Related Problems and were classified into 28 meaningful groups for the purpose of this article. In order to analyze multiple causes of death, simple frequencies were used in addition to principal components analysis to obtain the main groups of causes that contributed to death. RESULTS: The most frequent multiple causes of death were respiratory and cardiovascular diseases of the perinatal period (24.2% of all multiple causes), diseases related to growth and maturity of the fetus and the newborn (20.2%), congenital malformations (8.6%) and perinatal infections (7.6%). Principal components analysis revealed three major interpretable components: "post-neonatal, infectious and avoidable deaths", "complications of procedures and external causes" and "perinatal disorders, not related to low birth weight and/or immaturity". CONCLUSION: By using principal components analysis it was easier to understand how the multiple causes were associated. This is more interesting for Public Health purposes, because it may help clarify the steps in disease causation

Organocatalytic enantio- and diastereoselective cycloetherification via dynamic kinetic resolution of chiral cyanohydrins

特定の分子にのみ反応する酵素の特徴を応用し精密有機合成を実現 --薬剤候補物質の効率的な合成へ--. 京都大学プレスリリース. 2017-11-14.Enantioselective approaches to synthesize six-membered oxacycles with multiple stereogenic centres are in high demand to enable the discovery of new therapeutic agents. Here we present a concise organocatalytic cycloetherification for the highly enantio- and diastereoselective synthesis of tetrahydropyrans involving simultaneous construction of two chiral centres, one of which is fully substituted. This method involves dynamic kinetic resolution of reversibly generated chiral cyanohydrins. A chiral bifunctional organocatalyst selectively recognizes a specific chair-like conformation of the intermediate, in which the small steric effect of the linear cyano group as well as its anomeric effect play important roles in controlling stereoselectivity. The products offer additional utility as synthetic intermediates because the cyano group can be further transformed into a variety of important functional groups. This strategy provides a platform to design efficient approaches to obtain a wide range of optically active tetrahydropyrans, which are otherwise synthetically challenging materials