The VAST BioImager system is a set of tools developed for zebrafish researchers who require the c... more The VAST BioImager system is a set of tools developed for zebrafish researchers who require the collection of images from a large number of 2-7 dpf zebrafish larvae. The VAST BioImager automates larval handling, positioning and orientation tasks. Color images at about 10μm resolution are collected from the on-board camera of the system. If images of greater resolution and detail are required, this system is mounted on an upright microscope, such as a confocal or fluorescence microscope, to utilize their capabilities. The system loads a larvae, positions it in view of the camera, determines orientation using pattern recognition analysis, and then more precisely positions to user-defined orientation for optimal imaging of any desired tissue or organ system. Multiple images of the same larva can be collected. The specific part of each larva and the desired orientation and position is identified by the researcher and an experiment defining the settings and a series of steps can be saved and repeated for imaging of subsequent larvae. The system captures images, then ejects and loads another larva from either a bulk reservoir, a well of a 96 well plate using the LP Sampler, or individually targeted larvae from a Petri dish or other container using the VAST Pipettor. Alternative manual protocols for handling larvae for image collection are tedious and time consuming. The VAST BioImager automates these steps to allow for greater throughput of assays and screens requiring high-content image collection of zebrafish larvae such as might be used in drug discovery and toxicology studies.
The COPAS Biosorter is a flow cytometer designed to accommodate large objects the size of Caenorh... more The COPAS Biosorter is a flow cytometer designed to accommodate large objects the size of Caenorhabditis elegans. This instrumentation brings high-speed automated analysis and sorting to this small model organism. The Biosort system optically analyzes and sorts living multicellular organisms on the basis of fluorescent protein expression patterns and other optical signatures, at rates up to about 100 organisms per second. The Biosort is capable of fluorescently analyzing and sorting multicellular organisms that are many-fold larger than single cells. Animals pass through a laser beam focused to the center of the flow cell. This beam is narrower than the animal so that multiple measurements are made per animal, which means that the organism is optically scanned along its long axis as it flows. Stable laminar flow in the flow cell acts to orientate the animal with the flow stream. Fluorescent locations along the axis of the animal are sequentially excited as the organism flows through the line of focus. The fluorescent properties of commonly used reagents in the research field allow the user to detect fluorescent protein expression, lectin and antibody binding, and autofluorescence. The ability to dispense organisms as they emerge from the flow cell allows for the collection of those organisms that have certain optical properties defined by the researcher. Also, dispensing allows for the precise distribution of specific numbers of animals for analysis that can vary with organism numbers.
We have investigated the structural features of spontaneous deletions in Caenorhabditis elegans. ... more We have investigated the structural features of spontaneous deletions in Caenorhabditis elegans. We cloned and sequenced the junctions of 16 spontaneous deletions affecting the unc-54 myosin heavy-chain gene and compared their sequences with those of the wild type. We analyzed these sequences in an attempt to identify structural features of the gene that are consistently involved in the spontaneous deletion process. Most deletions (15 of 16) removed a single contiguous region of DNA, with no nucleotides inserted or rearranged at the deletion junctions; one deletion was more complex. unc-54 deletions were small, averaging 600 base pairs in length, and were randomly distributed throughout the gene. Unlike deletions that occur in Escherichia coli, spontaneous unc-54 deletions did not contain statistically significant direct or inverted repeats at or near their termini. Except for their small average size, we have not identified any distinguishing features of their sequence or structure...
(24) Nesmeyanov, A. N.; Freidlina, R. K. H. Zakharkin, L. I. Dokl. Akad. Nauk. SSSR 1954,97,91-94... more (24) Nesmeyanov, A. N.; Freidlina, R. K. H. Zakharkin, L. I. Dokl. Akad. Nauk. SSSR 1954,97,91-94; Chem. Abstr. 1955,49,8793. (25) V'yunov, K. A; Zhukova, T. I.; Sochilin, E. G.; Smorygo, NA Zh. Org. Khim. 1976,11, 2331-2335. (26) V'yunov, KA; Garabadzhiu, A. W.; ...
The VAST BioImager system is a set of tools developed for zebrafish researchers who require the c... more The VAST BioImager system is a set of tools developed for zebrafish researchers who require the collection of images from a large number of 2-7 dpf zebrafish larvae. The VAST BioImager automates larval handling, positioning and orientation tasks. Color images at about 10μm resolution are collected from the on-board camera of the system. If images of greater resolution and detail are required, this system is mounted on an upright microscope, such as a confocal or fluorescence microscope, to utilize their capabilities. The system loads a larvae, positions it in view of the camera, determines orientation using pattern recognition analysis, and then more precisely positions to user-defined orientation for optimal imaging of any desired tissue or organ system. Multiple images of the same larva can be collected. The specific part of each larva and the desired orientation and position is identified by the researcher and an experiment defining the settings and a series of steps can be saved and repeated for imaging of subsequent larvae. The system captures images, then ejects and loads another larva from either a bulk reservoir, a well of a 96 well plate using the LP Sampler, or individually targeted larvae from a Petri dish or other container using the VAST Pipettor. Alternative manual protocols for handling larvae for image collection are tedious and time consuming. The VAST BioImager automates these steps to allow for greater throughput of assays and screens requiring high-content image collection of zebrafish larvae such as might be used in drug discovery and toxicology studies.
The COPAS Biosorter is a flow cytometer designed to accommodate large objects the size of Caenorh... more The COPAS Biosorter is a flow cytometer designed to accommodate large objects the size of Caenorhabditis elegans. This instrumentation brings high-speed automated analysis and sorting to this small model organism. The Biosort system optically analyzes and sorts living multicellular organisms on the basis of fluorescent protein expression patterns and other optical signatures, at rates up to about 100 organisms per second. The Biosort is capable of fluorescently analyzing and sorting multicellular organisms that are many-fold larger than single cells. Animals pass through a laser beam focused to the center of the flow cell. This beam is narrower than the animal so that multiple measurements are made per animal, which means that the organism is optically scanned along its long axis as it flows. Stable laminar flow in the flow cell acts to orientate the animal with the flow stream. Fluorescent locations along the axis of the animal are sequentially excited as the organism flows through the line of focus. The fluorescent properties of commonly used reagents in the research field allow the user to detect fluorescent protein expression, lectin and antibody binding, and autofluorescence. The ability to dispense organisms as they emerge from the flow cell allows for the collection of those organisms that have certain optical properties defined by the researcher. Also, dispensing allows for the precise distribution of specific numbers of animals for analysis that can vary with organism numbers.
We have investigated the structural features of spontaneous deletions in Caenorhabditis elegans. ... more We have investigated the structural features of spontaneous deletions in Caenorhabditis elegans. We cloned and sequenced the junctions of 16 spontaneous deletions affecting the unc-54 myosin heavy-chain gene and compared their sequences with those of the wild type. We analyzed these sequences in an attempt to identify structural features of the gene that are consistently involved in the spontaneous deletion process. Most deletions (15 of 16) removed a single contiguous region of DNA, with no nucleotides inserted or rearranged at the deletion junctions; one deletion was more complex. unc-54 deletions were small, averaging 600 base pairs in length, and were randomly distributed throughout the gene. Unlike deletions that occur in Escherichia coli, spontaneous unc-54 deletions did not contain statistically significant direct or inverted repeats at or near their termini. Except for their small average size, we have not identified any distinguishing features of their sequence or structure...
(24) Nesmeyanov, A. N.; Freidlina, R. K. H. Zakharkin, L. I. Dokl. Akad. Nauk. SSSR 1954,97,91-94... more (24) Nesmeyanov, A. N.; Freidlina, R. K. H. Zakharkin, L. I. Dokl. Akad. Nauk. SSSR 1954,97,91-94; Chem. Abstr. 1955,49,8793. (25) V'yunov, K. A; Zhukova, T. I.; Sochilin, E. G.; Smorygo, NA Zh. Org. Khim. 1976,11, 2331-2335. (26) V'yunov, KA; Garabadzhiu, A. W.; ...
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