Abnormalities in the spindles (the bi-polar thread like structures that link and pull the chromosomes during cell division) of human embryos before implantation may be the primary reason for many of the chromosome defects observed in early human development, a scientist said on Wednesday 30 June 2004 at the 20th annual conference of the European Society of Human Reproduction and Embryology. Dr. Katerina Chatzimeletiou, from the Bridge Fertility Centre, London, UK, told the conference that her research had shown for the first time that such abnormalities occur throughout the development of the pre-implantation embryo.
“Use of the diagnostic technique fluorescence in situ hybridisation (FISH), that utilises fluorescence probes to identify specific chromosomes, has previously revealed a large number of chromosomal abnormalities including ‘chaos’ in embryos before implantation”, she said. “Up till now it was believed that these may be due to technical artefacts and not representative of the true status of the embryos. Our work has shown that this is not the case. In fact, we have identified a major pathway leading to chromosomal and nuclear abnormalities in the preimplantation embryo in vitro.”
During cell division, spindle fibres align the 46 chromosomes along the middle of the cell and then forces are exerted that pull the chromosomes to opposite directions. A bi-polar spindle ensures that each of the two daughter cells receives a copy of each of the 46 chromosomes. Dr. Chatzimeletiou’s team found that some spindles in cleavage and blastocyst stage embryos contain more than two poles (tripolar or tetraplolar), and in those it is impossible for the 46 chromosomes to be segregated equally to two daughter cells, as they would be pulled to three or more directions. “This in turn inevitably leads to chromosomal chaos”, she said.
Emma Mason | alfa
During HIV infection, antibody can block B cells from fighting pathogens
14.08.2018 | NIH/National Institute of Allergy and Infectious Diseases
First study on physical properties of giant cancer cells may inform new treatments
14.08.2018 | Brown University
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.
Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
14.08.2018 | Information Technology
14.08.2018 | Life Sciences
14.08.2018 | Life Sciences