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Digital Microscopy (digital + microscopy)
Selected AbstractsEstimation of Centres and Radial Intensity Profiles of Spherical Nano-Particles in Digital MicroscopyBIOMETRICAL JOURNAL, Issue 2 2007Mats Kvarnström Abstract Control of the microscopic characteristics of colloidal systems is critical in a wealth of application areas, ranging from food to pharmaceuticals. To assist in estimating these characteristics, we present a method for estimating the positions of spherical nano-particles in digital microscopy images. The radial intensity profiles of particles, which depend on the distances of the particles from the focal plane of the light microscope and have no closed functional form, are modelled using a local quadratic kernel estimate. We also allow for the case where pixel values are censored at an upper limit of 255. Standard errors of centre estimates are obtained using a sandwich estimator which takes into account spatial autocorrelation in the errors. The approach is validated by a simulation study. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Gastroduodenal reflux induces group IIa secretory phospholipase A2 expression and activity in murine esophagusDISEASES OF THE ESOPHAGUS, Issue 5 2010David Mauchley SUMMARY Exposure of esophageal epithelium to gastric and duodenal contents results in the histologic changes of hyperproliferation and mucosal thickening. We have previously shown that presence of secretory phospholipase A2 (sPLA2) is necessary to produce these histologic changes in a murine model of gastroduodenal reflux. We sought to determine the influence of gastroduodenal reflux (GDR) on sPLA2 protein and mRNA levels as well as enzyme activity in esophageal tissue. BALB/c (sPLA2+/+) mice (n= 28) underwent side-to-side surgical anastomosis of the first portion of the duodenum and GE junction (DGEA) resulting in continuous exposure of esophageal mucosa to mixed gastric and duodenal contents. Sham control mice (n= 14) underwent laparotomy, esophagotomy and closure. Real-time RT PCR was used to quantitate the influence of GDR on group IIa sPLA2 expression. Immunofluorescent staining was quantitated by digital microscopy using a specific antibody to identify and locate sPLA2 protein. A colorimetric assay was used to quantify total sPLA2 activity after standardization of protein levels. Statistical analysis was conducted using Student's t -test. Group IIa sPLA2 mRNA and protein levels were increased at 4 and 8 weeks compared with sham controls. This increase occurred in a time-dependent manner and correlated with esophageal mucosal thickness. Furthermore, sPLA2 enzyme activity was increased significantly at 4 and 8 weeks compared with untreated controls. The expression of group IIa sPLA2 as well as sPLA2 activity is induced by GDR. This novel finding indicates that sPLA2 may play a role in the development of the histologic changes produced by GDR in esophageal mucosa. [source] Halo naevus is associated with leucotrichia: use of portable digital microscopyJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 9 2009D-Y Lee [source] A new model organism among the lower Bilateria and the use of digital microscopy in taxonomy of meiobenthic Platyhelminthes: Macrostomum lignano, n. sp. (Rhabditophora, Macrostomorpha)JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 2 2005P. Ladurner Abstract Macrostomum lignano n. sp. is a member of the Macrostomorpha, the basal-most subtaxon of the Platyhelminthes,Rhabditophora. This new species can be easily cultured in the laboratory and has been already the subject of several developmental/evolutionary studies. The small size, with only about 25 000 cells constituting the major bilaterian organ systems, makes this simultaneous hermaphrodite a possible candidate for a new model organism that is phylogenetically more basal than any of the model organisms currently used in such studies within the Bilateria. M. lignano belongs to the largest genus of the Macrostomorpha. Over 100 marine, fresh water and brackish water species are contained in the genus Macrostomum, some of them with worldwide distribution pattern. Within it, M. lignano is a member of the M. tuba -species group, which we have summarized here. In the species description, we have used a novel approach to document such small soft-bodied meiobenthic organisms: we provide extensive digital micrographical documentation, which are deposited as a CD together with the type material. Zusammenfassung Macrostomum lignano n. sp. gehört zu den Macrostomorpha, dem ursprünglichsten Subtaxon der Plathelminthes-Rhabditophora. An der neuen Art, die sich im Labor besonders einfach züchten lässt, wurden bereits zahlreiche entwicklungsbiologische und evolutionsbiologische Studien durchgeführt. Die kleinen simultan-hermaphroditischen Tiere, bei denen nur etwa 25'000 Zellen alle wichtigen Organsysteme der Bilateria ausbilden, sind für derartige Untersuchungen ein möglicher Modellorganismus, der phylogenetisch weit ursprünglicher ist als die üblichen Modellorganismen. Macrostomum ist die größte Gattung der Macrostomorpha. Sie umfasst mehr als 100 Meer-, Süss- und Brackwasser-Arten, einige davon mit weltweiter Verbreitung. Innerhalb der Gattung ist M. lignano der M. tuba -Artengruppe zuzurechnen, die zusammenfassend dargestellt wird. Zur Charakterisierung dieser meiobenthischen neuen Art wird als neuartige Dokumentationsform digitales Bildmaterial verwendet, das als CD zusammen mit dem Typenmaterial hinterlegt wird. [source] Cluster computing for digital microscopyMICROSCOPY RESEARCH AND TECHNIQUE, Issue 2 2004Walter A. Carrington Abstract Microscopy is becoming increasingly digital and dependent on computation. Some of the computational tasks in microscopy are computationally intense, such as image restoration (deconvolution), some optical calculations, image segmentation, and image analysis. Several modern microscope technologies enable the acquisition of very large data sets. 3D imaging of live cells over time, multispectral imaging, very large tiled 3D images of thick samples, or images from high throughput biology all can produce extremely large images. These large data sets place a very large burden on laboratory computer resources. This combination of computationally intensive tasks and larger data sizes can easily exceed the capability of single personal computers. The large multiprocessor computers that are the traditional technology for larger tasks are too expensive for most laboratories. An alternative approach is to use a number of inexpensive personal computers as a cluster; that is, use multiple networked computers programmed to run the problem in parallel on all the computers in the cluster. By the use of relatively inexpensive over-the-counter hardware and open source software, this approach can be much more cost effective for many tasks. We discuss the different computer architectures available, and their advantages and disadvantages. Microsc. Res. Tech. 64:204,213, 2004. © 2004 Wiley-Liss, Inc. [source] Active Participation Instead of Passive Behaviour Opens Up New Vistas in Education of Veterinary Anatomy and HistologyANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2009J. Plendl Summary Teaching morphology, a fundamental part of medicine curricula is traditionally based on lectures and practical trainings. We introduced peer-assisted learning (PAL) and student expert teams to the courses to give the students the possibility to improve their free speech and self-confidence. We involved students in active preparation of online materials such as labelled e-slides and e-pics. We offered online digital microscopy (ZoomifyTM) and dissection (CyberPrep) allowing repeating the learned material and studying veterinary morphology outside the dissection theatre. Over 60% of first and third semester students profited from being a peer or being taught by a peer and 50% said the expert teams were an excellent method to learn the topographic anatomy. Almost all students applied ZoomifyTM and CyberPrep and 75% of them found the digital microscopy and dissection to be a helpful or very helpful learning tool. In face of reduced contact hours, these forms of education compensated in part the lost teaching time. We observed improvement of rhetoric and presentation skills and self-confidence. The approaches should therefore find their constant place in the veterinary medicine curricula. [source] | |||||||||||||