584 research outputs found
Assays for mitotic chromosome condensation in live yeast and mammalian cells
The dynamic reorganization of chromatin into rigid and compact mitotic chromosomes is of fundamental importance for faithful chromosome segregation. Owing to the difficulty of investigating this process under physiological conditions, the exact morphological transitions and the molecular machinery driving chromosome condensation remain poorly defined. Here, we review how imaging-based methods can be used to quantitate chromosome condensation in vivo, focusing on yeast and animal tissue culture cells as widely used model systems. We discuss approaches how to address structural dynamics of condensing chromosomes and chromosome segments, as well as to probe for mechanical properties of mitotic chromosomes. Application of such methods to systematic perturbation studies will provide a means to reveal the molecular networks underlying the regulation of mitotic chromosome condensatio
Using graphical style and visibility constraints for a meaningful layout in visual programming interfaces
In the expanding field of visual applications, layout design and graphical editing tasks are crucial points. In this paper, we address the incorporation of AI aspects in the visual software design process and the automatic layout and beautification of informational graphics such as visual programs and chart diagrams. Since layout in dynamic settings frequently requires a direct manipulation responsiveness, an incremental redesign of the generated visual material is necessary. Following our previous work on constraint-based multimodal design, we show how powerful constraint processing techniques, such as constraint hierarchies and dynamic constraint satisfaction, can be applied to visual programming environments in order to maintain graphical style and consistency for a meaningful layout. We describe InLay, a system for constraint-based presenting and editing visual programs. Finally, we will have a short look at some extensions with regard to advanced interaction and visualization techniques
Base stacking interactions of L-histidine and thyrotropin-releasing hormone with adenosine-5âČ-monophosphate
Origin and outcome of multiple pregnancies in Bern, Switzerland, 1995-2006 and the current proposal of the Swiss parliament to revise the Swiss law of reproductive medicine: Switzerland quo vadis?
INTRODUCTION: Infertility treatments are a major source of the increase in multiple pregnancies (MPs).
AIMS: The aims of the present study were (1.) to investigate the origin and maternal/neonatal outcomes of MP and (2.) to review the different measures that can be adopted to reduce these serious complications.
METHODS: The study included all women with multiple births between 1 January 1995 and 31 December 2006 at the University Hospital of Bern, Switzerland. The outcomes associated with the various origins of MP (natural conception, ovarian stimulation [OS] â in-vitro fertilisation [IVF-ICSI]) were analysed using a multinomial logistic regression model. An analysis of the Swiss law on reproductive medicine and its current proposed revision, as well as a literature review using Pubmed, was carried out.
RESULTS: A total of 592 MP were registered, 91% (n = 537) resulted in live births. There was significantly more neonatal/maternal morbidity in MP after OS compared with natural conception and even with the IVF-ICSI group. With a policy of elective single embryo transfer (eSET), twin rates after IVF-ICSI can be reduced to <5% and triplets to <1%.
CONCLUSIONS: After OS, more triplets are found and the outcome of MP is worse. MP is known to be associated with morbidity, mortality, and economic and social risks. To counteract these complications (1.) better training for physicians performing OS should be encouraged and (2.) the Swiss law on reproductive medicine needs to be changed, with the introduction of eSET policies. This would lead to a dramatic decrease in neonatal and maternal morbidity/mortality as well as significant cost reductions for the Swiss healthcare system
Ălaboration de cocristaux pharmaceutiques par procĂ©dĂ©s assistĂ©s au CO2
For the pharmaceutical industry, cocrystal design allows tuning physicochemical propertiesof an active compound without altering its therapeutic activity. These monophasic solidscontain two or more different species interacting by weak and neutral bonds. Whereas themajority of cocrystallization studies pertain to generation and characterization of newcocrystalline phases, this work was aiming at exploring a new way of cocrystal fabrication,using supercritical CO2-assisted processes. The possibility of interaction formation betweendifferent types of compounds when these are precipitated by antisolvent CO2 has beenstudied by the batch GAS (Gaseous Anti-Solvent) and the semi-continuous SAS(Supercritical Anti-Solvent) versions of the antisolvent method on two different molecularsystems: naproxen-nicotinamide and acetazolamide-theophylline. Naproxen being a chiralcompound, its cocrystallization with nicotinamide from a racemic mixture has also beenaddressed. A known naproxen-based cocrystal and a new racemic cocrystalline phase havebeen obtained thanks to the antisolvent precipitation. A new acetazolamide-theophyllinecocrystal has also been produced for the first time with the GAS process. The influence ofGAS and SAS operational parameters such as CO2 feed rate, species molar ratio andconcentrations in the initial solution, has been investigated to allow a better understanding ofthe mechanisms involved in supercritical CO2-induced cocrystallization. Results have shownthat purity in cocrystal of the produced powders is influenced by the CO2 composition of thesolution/antisolvent mixture and by the ratio and concentrations of the solutes(thermodynamic equilibria), but also by the homogeneity of the mixture in the precipitationchamber of the process.Pour lâindustrie pharmaceutique, la conception de cocristaux permet de moduler les propriĂ©tĂ©s physico-chimiques de composĂ©s dâintĂ©rĂȘt sans en altĂ©rer lâactivitĂ© thĂ©rapeutique.Ces solides monophasĂ©s sont dĂ©finis comme Ă©tant des structures comportant plusieurs espĂšces reliĂ©es entre elles par des liaisons faibles et neutres. Alors que la majoritĂ© des Ă©tudes de cocristallisation sont centrĂ©es sur la gĂ©nĂ©ration et la caractĂ©risation de nouvelles phases, ce travail a eu pour objectif dâexplorer une nouvelle mĂ©thode de fabrication de cocristaux, en utilisant des procĂ©dĂ©s assistĂ©s au CO2 supercritique. La possibilitĂ© de formerdes interactions entre composĂ©s de diffĂ©rentes natures par recristallisation au CO2antisolvant a Ă©tĂ© Ă©tudiĂ©e avec les versions discontinue GAS (Gaseous Anti-Solvent) et semicontinue SAS (Supercritical Anti-Solvent) sur deux systĂšmes: naproxĂšne-nicotinamide et acĂ©tazolamide-thĂ©ophylline. Le naproxĂšne Ă©tant chiral, la cocristallisation Ă partir du mĂ©lange naproxĂšne racĂ©mique-nicotinamide a Ă©galement Ă©tĂ© abordĂ©e. Un cocristal connu etdeux phases cocristallines jamais observĂ©es, dont une racĂ©mique, ont pu ĂȘtre synthĂ©tisĂ©s.LâĂ©tude de lâinfluence de divers paramĂštres opĂ©ratoires des procĂ©dĂ©s GAS et SAS, tels que la concentration de la solution initiale, le ratio des espĂšces ou le dĂ©bit dâajout de lâantisolvant,a permis une meilleure comprĂ©hension de la cocristallisation induite par CO2 supercritique.Les rĂ©sultats ont montrĂ© que la puretĂ© en cocristaux des poudres obtenues Ă©tait influencĂ©e Ă la fois par la proportion de CO2 dans le mĂ©lange solution/CO2 et les concentrations des espĂšces en solution (contribution des Ă©quilibres thermodynamiques) mais Ă©galement par lâhomogĂ©nĂ©itĂ© du rĂ©acteur de prĂ©cipitation
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