Search results for " Structures"
showing 10 items of 4162 documents
Prediction model for aneuploidy in early human embryo development revealed by single-cell analysis.
2014
Aneuploidies are prevalent in the human embryo and impair proper development, leading to cell cycle arrest. Recent advances in imaging and molecular and genetic analyses are postulated as promising strategies to unveil the mechanisms involved in aneuploidy generation. Here we combine time-lapse, complete chromosomal assessment and single-cell RT–qPCR to simultaneously obtain information from all cells that compose a human embryo until the approximately eight-cell stage (n=85). Our data indicate that the chromosomal status of aneuploid embryos (n=26), including those that are mosaic (n=3), correlates with significant differences in the duration of the first mitotic phase when compared with e…
Sea Urchin Mitochondrial Matrix Contains a 56-kDa Chaperonine-like Protein
1997
Abstract Paracentrotus lividus mitochondrial matrix contains a constitutive hsp of 56-KDa which cross reacts with a serum anti-hsp-60 chaperonine from yeast mitochondria. The localization of hsps preexisting or newly synthesized in different subcellular fractions of gastrula embryos is also analyzed by two-dimensional electrophoresis.
A contribution to the study of staling of white bread: effect of water and hydrocolloid
1996
Abstract Staling of white bread at ambient temperature was studied using differential scanning calorimetry and dynamic mechanical thermal analysis. During storage, sample hydration varied slightly, from 0 to 0.4% per day, depending on packaging conditions. An increase in rigidity was observed, which was attributed both to starch retrogradation and to changes in the organization of the amorphous part of crumb. The glass transition temperature of crumb was not significantly modified by these structural changes. Hydrocolloids did not affect the overall shape of the viscoelastic behavior of crumb in the temperature range from −40°C to 80°C, and had a limited influence on the kinetics of starch …
Determination of the LD50 with the chick embryo chorioallantoic membrane (CAM) assay as a promising alternative in nanotoxicological evaluation
2021
Toxicity tests in rodents are still considered a controversial topic concerning their ethical justifiability. The chick embryo chorioallantoic membrane (CAM) assay may offer a simple and inexpensive alternative. The CAM assay is easy to perform and has low bureaucratic hurdles. At the same time, the CAM assay allows the application of a broad variety of analytical methods in the field of nanotoxicological research. We evaluated the CAM assay as a methodology for the determination of nanotoxicity. Therefore we calculated the median lethal dose (LD50), performed in vivo microscopy and immunohistochemistry to identify organ-specific accumulation profiles, potential organ damage, and the kineti…
A factor derived from chick embryo retina which inhibits DNA synthesis of retina itself.
1992
Chick embryo retinas contain a peptide factor that inhibits DNA synthesis in explants of chick embryo retina. The inhibitory factor, obtained by acid/ethanol extraction from 15-day-old chick embryo retinas, was partially purified by affinity chromatography on heparin-sepharose CL-6B and gel filtration on Sephadex G-100. The inhibitor reduced DNA synthesis with maximal effects observed in retinal explants from 7 to 8-day-old chick embryos. The inhibitory effect became apparent after 10 h of incubation and reached the maximum levels after 16 h. DNA-inhibiting activity was heat and acid-stable and was destroyed by trypsin and alkaline treatments. The inhibitory effect was observed in retinal e…
Oil-In-Water Microemulsion Liquid Chromatography
2018
Oil-in-water microemulsions (O/W MEs) are obtained spontaneously by mixing two immiscible liquids (water and oil) in the presence of a surfactant. A co-surfactant is also often needed for ME stabil...
Surface active and emulsifying properties of casein micelles compared to those of sodium caseinate
1999
Emulsions prepared using casein micelles and sodium caseinate as the emulsifying agent are compared. It is found that the ultrastructure of the casein proteins influences the properties of the emulsion.
Tracing the origin of the compensasome: evolutionary history of DEAH helicase and MYST acetyltransferase gene families.
2001
Dosage compensation in Drosophila is mediated by a complex of proteins and RNAs called the "compensasome." Two of the genes that encode proteins of the complex, maleless (mle) and males-absent-on-the-first (mof), respectively, belong to the DEAH helicase and MYST acetyltransferase gene families. We performed comprehensive phylogenetic and structural analyses to determine the evolutionary histories of these two gene families and thus to better understand the origin of the compensasome. All of the members of the DEAH and MYST families of the completely sequenced Saccharomyces cerevisiae and Caenorhabditis elegans genomes, as well as those so far (June 2000) found in Drosophila melanogaster (f…
Technostress and social networking services: Explaining users' concentration, sleep, identity, and social relation problems
2018
It is common for users of social networking sites and services (SNS) to suffer from technostress and the various associated strains that hinder their well‐being. Despite prior SNS stress studies having provided valuable knowledge regarding SNS stressors and their use consequences, they have not examined the various strains related to well‐being that those stressors can create nor the underlying SNS characteristics. To address this gap in the research, we used a qualitative approach involving narrative interviews. As a contribution, our findings reveal four types of strains related to well‐being (concentration problems, sleep problems, identity problems, and social relation problems) as well…
A novel pilot study of automatic identification of EMF radiation effect on brain using computer vision and machine learning
2020
Abstract Electromagnetic field (EMF) radiations from mobile phones and cell tower affect brain of humans and other organisms in many ways. Exposure to EMF could lead to neurological changes causing morphological or chemical changes in the brain and other internal organs. Cellular level analysis to measure and identify the effect of mobile radiations is an expensive and long process as it requires preparing the cell suspension for the analysis. This paper presents a novel pilot study to identify changes in brain morphology under EMF exposure considering drosophila melanogaster as a specimen. The brain is automatically segmented, obtaining microscopic images from which discriminatory geometri…