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Pregnancy Timeline by SemestersDevelopmental TimelineFertilizationFirst TrimesterSecond TrimesterThird TrimesterFirst Thin Layer of Skin AppearsEnd of Embryonic PeriodEnd of Embryonic PeriodFemale Reproductive SystemBeginning Cerebral HemispheresA Four Chambered HeartFirst Detectable Brain WavesThe Appearance of SomitesBasic Brain Structure in PlaceHeartbeat can be detectedHeartbeat can be detectedFinger and toe prints appearFinger and toe prints appearFetal sexual organs visibleBrown fat surrounds lymphatic systemBone marrow starts making blood cellsBone marrow starts making blood cellsInner Ear Bones HardenSensory brain waves begin to activateSensory brain waves begin to activateFetal liver is producing blood cellsBrain convolutions beginBrain convolutions beginImmune system beginningWhite fat begins to be madeHead may position into pelvisWhite fat begins to be madePeriod of rapid brain growthFull TermHead may position into pelvisImmune system beginningLungs begin to produce surfactant
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Developmental Biology - Imaging Technology

The mesoSPIM Initiative

New microscopes can image brain tissue down to individual neurons five times thinner than a human hair...

New microscopes, known as mesoSPIMs, can image the minute detail of brain tissue down to individual neurons five times thinner than a human hair, uncovering the 3D anatomy of entire small organs, faster than ever before.
MesoSPIMs provide new insight into brain and spinal cord organization for researchers working to restore movement after paralysis or to investigate neuronal networks involved in cognition, pleasure, or drug addiction.

The work supporting this new imaging appears in Nature Methods.

Because mesoSPIMs create high-resolution images of large samples faster than existing microscopes, they are beneficial for rapidly screening many samples. A new open-source initiative, made up of top European researchers in neuroscience, is driving dissemination of mesoSPIMs globally by sharing their expertise and excitement as well as stunning images and videos.

MesoSPIMs, short for 'mesoscale selective plane-illumination microscopes', are light-sheet microscopes. Unlike traditional microscopy in which specimens are cut in slices with a blade before being viewed on a slide under a microscope, light-sheet microscopes optically slice samples with a sheet of light. This optical sectioning captures slivers of image without damaging the sample. The imaged slices are then combined to reconstruct a detailed three-dimensional image of a whole organ or specimen.

The data sets produced by standard light-sheet microscopes are very large and analysing them is time consuming. MesoSPIMs get around this problem with innovative optical technologies that allow fast scanning as well as direct visualization and quantification of the captured data.
"We created the open-source mesoSPIM Initiative to share the latest developments in microscope instrumentation and software with the imaging community. Anyone seeking high-quality anatomical data from large samples now has the information they need to build and operate their own mesoSPIM."

Fabian Voigt PhD, Fritjof Helmchen group, Brain Research Institute, University of Zurich, Switzerland.

The power of the initiative lies in the insights brought from differing disciplines, such as physics, developmental biology and neuroscience which allows microscope development, and brain research, to flourish.

There are currently seven mesoSPIMs in operation across Europe and several more instruments under construction. One of the new mesoSPIMs is hosted by the Advanced Lightsheet Imaging Center (ALICe) at the Wyss Center. Open to external users, ALICe offers a complete pipeline from sample preparation to image analysis, under the scientific guidance of experts from the University of Geneva and the École Polytechnique Fédérale de Lausanne (EPFL).
"We are proud to have one of only seven mesoSPIM microscopes in the world at the Wyss Center. MesoSPIM microscopes solve the longstanding problem of how to achieve exceptional images in large samples over very short time-scales. We are delighted to be part of an initiative bringing this technology to the world."

Stéphane Pagès PhD, ALICe Scientific Coordinator.

The mesoSPIM Initiative is aimed at research groups and imaging facilities with experience in building and supporting custom microscopes. A mesoSPIM can be installed in few days and typically requires a budget of around $200K.

Light-sheet microscopy is an ideal technique for imaging large cleared samples; however, the community is still lacking instruments capable of producing volumetric images of centimeter-sized cleared samples with near-isotropic resolution within minutes. Here, we introduce the mesoscale selective plane-illumination microscopy initiative, an open-hardware project for building and operating a light-sheet microscope that addresses these challenges and is compatible with any type of cleared or expanded sample (www.mesospim.org).

Fabian F. Voigt, Daniel Kirschenbaum, Evgenia Platonova, Stéphane Pagès, Robert A. A. Campbell, Rahel Kastli, Martina Schaettin, Ladan Egolf, Alexander van der Bourg, Philipp Bethge, Karen Haenraets, Noémie Frézel, Thomas Topilko, Paola Perin, Daniel Hillier, Sven Hildebrand, Anna Schueth, Alard Roebroeck, Botond Roska, Esther T. Stoeckli, Roberto Pizzala, Nicolas Renier, Hanns Ulrich Zeilhofer, Theofanis Karayannis, Urs Ziegler, Laura Batti, Anthony Holtmaat, Christian Lüscher, Adriano Aguzzi and Fritjof Helmchen.

Acknowledgements This work was supported by grants from the Swiss National Science Foundation (grant nos. 31003A-149858, 31003B-170269 to F.H.; no. 31003A_170037 to T.K.; nos. 31003A-153448, 31003A_173125, CRSII3_154453 and NCCR Synapsy no. 51NF40-158776 to A.H.), the European Research Council (ERC Advanced Grant BRAINCOMPATH, project no. 670757 to F.H.), ERC Starting Grants (InterWiring, project no. 679175 to T.K. and MULTICONNECT, project no. 639938 to A.R.), the Dutch science foundation (NWO VIDI Grant, project no. 14637 to A.R.), a PhD fellowship by the Swiss Foundation for Excellence in Biomedical Research (to R.K.), a gift from a private foundation with public interest through the International Foundation for Research in Paraplegia (to A.H. and S.P.), and a Distinguished Scientist Award of the Nomis Foundation (to A.A.). In addition, we would like to thank D. Göckeritz-Dujmovic and S. Bichet for help with sample preparation and M. Wieckhorst for help with custom electronics.

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Sep 26 2019   Fetal Timeline   Maternal Timeline   News  

Developing nervous system of seven-day old chicken embryo captured by a mesoSPIM microscope.
CREDIT mesoSPIM Initiative.

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