A simple method for fitting Bělehrádek's equation to embryonic development data of zooplankton

Alan J. Edgar; T. E. Andrew

doi:10.1007/bf00007117

Determination of production capacity of circulated primordial germ cells (circulated-PGCs) of KUB chicken using lysis buffer ammonium chloride potassium (ACK)

Jurnal Ilmu Ternak dan Veteriner ◽

10.14334/jitv.v21i1.1315 ◽

2016 ◽

Vol 21 (1) ◽

pp. 55

Author(s):

Soni Sopiyana ◽

Iman Supriatna ◽

M. Agus Setiadi ◽

Mohamad Fahrudin

Keyword(s):

Embryonic Development ◽

Ammonium Chloride ◽

Germ Cells ◽

Primordial Germ Cells ◽

Production Capacity ◽

Development Stage ◽

Simple Method ◽

Average Production ◽

Short Period ◽

Lysis Buffer

In poultry embryos, primordial germ cells (PGCs) are progenitor cells for gametes, which have unique migration pathway. Primordial germ cells arise from epiblast in germinal crescent and circulate through the bloodstream for a short period of time, then leave blood vessel to migrate toward gonads. The aim of this study was to determine the potential production capacity of circulated-PGCs of KUB chicken at different developmental stages of embryo using a rapid and simple method. Seventy five KUB chicken fertile eggs were divided into five groups and incubated at 38.5 0C with a humidity of 60%. Hatching was set to the embryonic development stage of 14-18. The blood was collected through dorsal aorta using micropipette under microscope. The collected blood was placed in a 1.5 ml eppendorf tube which was previously filled with 100 µl phosphate buffered saline without Ca2+ and Mg2+ (PBS-) mixed with fetal bovine serum (FBS) with a ratio of 90%:10%. The PGCs were purified using lysis buffer ammonium chloride potassium method. The results showed that average production of circulated-PGCs per embryo of KUB chicken were significantly affected by stage of embryonic development (P <0.05). The average production of circulated-PGCs at stage 14, 15, 16, 17, and 18 were 37.9; 53.5; 49.8; 38.3; and 33.5 respectively. The number of circulated-PGCs was not different among stages 14, 17 nor 18. The highest number of circulated-PGCs of KUB chicken was obtained at stage 15, so that the isolation and collection of PGCs through the blood circulation was recommended in stage 15.Key Words: KUB Chicken, PGCs, Embryonic Development Stage, Ammonium Chloride Potassium

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Embryonic and Postembryonic Development in Bythotrephes cederstroemii

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f92-124 ◽

1992 ◽

Vol 49 (6) ◽

pp. 1118-1125 ◽

Cited By ~ 59

Author(s):

Peder M. Yurista

Keyword(s):

Embryonic Development ◽

Development Time ◽

Lake Michigan ◽

Field Work ◽

Postembryonic Development ◽

Complete Life Cycle ◽

Development Data ◽

Series Development ◽

Data Log ◽

Morphological Series

Laboratory observations were made of embryonic development time for parthenogenic Bythotrephes cederstroemii under differing temperatures spanning the range when Bythotrephes may be present in the plankton of Lake Michigan. Postembryonic development was documented for parthenogenically produced and sexually produced offspring. The complete life cycle of Bythotrephes was observed to have two distinct morphological series. Development time from birth to primaparity, consisting of three instars, was 14.0 ± 1.63 d at 12.7 °C for pathenogenically produced offspring. Development time at 12.7 °C for gametogenically produced offspring was 13.7 ± 1.57 d with four instars. Because parthenogenic eggs released into the brood sac of Bythotrephes do not become obvious until the embryo development is well advanced, a useful model for birth rate calculations in field work was developed based on observable morphological traits of the embryos within the brood sac. A curvilinear logarithmic model of development time (D, hours) as a function of temperature (T degrees Celsius) was fit to the embryonic development data: log (D) = 6.840–7.305log(T) + 2.490log(T)2.

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A simple way for producing holographic filters suitable for image improvement

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108271 ◽

1978 ◽

Vol 36 (1) ◽

pp. 226-227

Author(s):

K.-H. Herrmann ◽

E. Reuber ◽

P. Schiske

Keyword(s):

Transfer Functions ◽

Diffraction Order ◽

Lateral Position ◽

Simple Method ◽

Spatial Frequencies ◽

Resolution Electron ◽

Wiener Filters ◽

Image Improvement ◽

Optical Reconstruction ◽

Set Up

Aposteriori deblurring of high resolution electron micrographs of weak phase objects can be performed by holographic filters [1,2] which are arranged in the Fourier domain of a light-optical reconstruction set-up. According to the diffraction efficiency and the lateral position of the grating structure, the filters permit adjustment of the amplitudes and phases of the spatial frequencies in the image which is obtained in the first diffraction order.In the case of bright field imaging with axial illumination, the Contrast Transfer Functions (CTF) are oscillating, but real. For different imageforming conditions and several signal-to-noise ratios an extensive set of Wiener-filters should be available. A simple method of producing such filters by only photographic and mechanical means will be described here.A transparent master grating with 6.25 lines/mm and 160 mm diameter was produced by a high precision computer plotter. It is photographed through a rotating mask, plotted by a standard plotter.

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Rotary Beveling for In Situ Thin-Section Microscopy of Cell Cultures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099192 ◽

1981 ◽

Vol 39 ◽

pp. 550-551

Author(s):

Dean A. Handley ◽

Jack T. Alexander ◽

Shu Chien

Keyword(s):

Cell Growth ◽

Cell Cultures ◽

Molecular Interactions ◽

Convenient Method ◽

Petri Dish ◽

Simple Method ◽

Thin Section Microscopy ◽

Thin Sectioning ◽

Organic Fluids

In situ preparation of cell cultures for ultrastructural investigations is a convenient method by which fixation, dehydration and embedment are carried out in the culture petri dish. The in situ method offers the advantage of preserving the native orientation of cell-cell interactions, junctional regions and overlapping configurations. In order to section after embedment, the petri dish is usually separated from the polymerized resin by either differential cryo-contraction or solvation in organic fluids. The remaining resin block must be re-embedded before sectioning. Although removal of the petri dish may not disrupt the native cellular geometry, it does sacrifice what is now recognized as an important characteristic of cell growth: cell-substratum molecular interactions. To preserve the topographic cell-substratum relationship, we developed a simple method of tapered rotary beveling to reduce the petri dish thickness to a dimension suitable for direct thin sectioning.

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Live Confocal Analysis of Fertilization and Early Development

Microscopy and Microanalysis ◽

10.1017/s1431927600031135 ◽

2001 ◽

Vol 7 (S2) ◽

pp. 1012-1013

Author(s):

Uyen Tram ◽

William Sullivan

Keyword(s):

Drosophila Melanogaster ◽

Embryonic Development ◽

Real Time ◽

Early Development ◽

Fluorescent Probes ◽

Primary Defect ◽

Fluorescent Analysis ◽

Dynamic Event ◽

Enormous Amount ◽

Fluorescent Studies

Embryonic development is a dynamic event and is best studied in live animals in real time. Much of our knowledge of the early events of embryogenesis, however, comes from immunofluourescent analysis of fixed embryos. While these studies provide an enormous amount of information about the organization of different structures during development, they can give only a static glimpse of a very dynamic event. More recently real-time fluorescent studies of living embryos have become much more routine and have given new insights to how different structures and organelles (chromosomes, centrosomes, cytoskeleton, etc.) are coordinately regulated. This is in large part due to the development of commercially available fluorescent probes, GFP technology, and newly developed sensitive fluorescent microscopes. For example, live confocal fluorescent analysis proved essential in determining the primary defect in mutations that disrupt early nuclear divisions in Drosophila melanogaster. For organisms in which GPF transgenics is not available, fluorescent probes that label DNA, microtubules, and actin are available for microinjection.

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