Cells may vary in numbers per embryo, be uneven-sized or partially fragmented. Dr Lieberman et al. at the Department of Obstetrics, Gynaecology and Reproductive Biology at the Brigham and Women’s Hospital, Harvard Medical School in Boston, USA have measured the quality of human embryos by counting and assessing the properties of their individual cells. In their paper Rate of cell division and weight of neonates following in-vitro fertilization, they compared the weights of 447 singleton births against cell numbers in embryos when transferred. Earlier reports suggest the possibility that such factors may influence birthweight or anomalies in children. This research, published in the journal Reproductive BioMedicine Online, [www.rbmonline.com/Article/2093 – e-pub ahead of print 1 February 2006] indicates that embryos with fewer cells may produce lightweight babies.
All women who conceived by IVF in their Hospital between 1998 and 2001 were included. Those who lost one or more fetuses during pregnancy, had pre-term births and delivered babies with congenital anomalies (3 cases) were excluded. Embryos scored for their cell number, stage of growth and morphology were transferred 3 days post-fertilization. Mean birthweights of babies produced from embryos with 7 or 8 cells of good symmetry and few fragments were compared with those produced from embryos with <7 or >8 cells.
Gestational ages were also assessed, and the data were adjusted according to numbers of replaced embryos, culture media, maternal age and fetal sex. Sub-groups of women were also analysed. 21% of the patients had embryos transferred with <7 cells, 61% with 7–8 cells, and 18% with >8 cells. Relative birthweights were 3388, 3452 and 3550 g respectively, differences between the lowest and highest groups being statistically significant. Each additional embryonic cell added an average of 42.7 g to birthweights. Other variables analysed included the consequences of assisted ‘hatching’ of embryos in particular patients.
Dr Catherine Racowsky | alfa
Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University
How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy