Cellular damage and recovery of the early developing mouse eye following low dose irradiation. I. X-rays on day 8 of gestation

Summary The eye region of mouse embryos, irradiated with 90 rad X-rays on day 8 of gestation, was examined 24 h later for cellular damage. Besides the overall developmental retardation, the radiation insult decreased the proliferation rate and altered the mitotic phase ratio. Due to the limited extension of necrotic zones, a reduced number of dead cells was found in the irradiated optic vesicles.Supported by the Swiss National Foundation for Scientific Research. The technical assistance of Mrs E. Frei is gratefully acknowledged.     

Serum iodothyronine concentrations and properties of mitochondria phosphorylative oxidations in old rats]

Serum concentrations of T4 and T3 in 2 year-old Rats were decreased by about 30% compared to 2 month-old animals, but rT3 was similar. Activities of old Rats' liver mitochondria were near those of young thyroidectomized animals. Low circulating T3 partly explains metabolic changes observed during senescence.     

Why not Post-Political?

This commentary on Gert Goeminne’s paper “Postphenomenology and the politics of sustainable technology” elaborates on the subpolitics of technology as a basis for dealing with sustainability issues. It questions the “sustainable technology” phrasing of the issue and focuses on the political/post-political debate to eventually suggest that the politics of sustainable technology is a possible post-political question. Minor disagreements on some philosophy of science references are briefly expressed.     

DNA damage defines sites of recurrent chromosomal translocations in B lymphocytes

Recurrent chromosomal translocations underlie both haematopoietic and solid tumours. Their origin has been ascribed to selection of random rearrangements, targeted DNA damage, or frequent nuclear interactions between translocation partners; however, the relative contribution of each of these elements has not been measured directly or on a large scale. Here we examine the role of nuclear architecture and frequency of DNA damage in the genesis of chromosomal translocations by measuring these parameters simultaneously in cultured mouse B lymphocytes. In the absence of recurrent DNA damage, translocations between Igh or Myc and all other genes are directly related to their contact frequency. Conversely, translocations associated with recurrent site-directed DNA damage are proportional to the rate of DNA break formation, as measured by replication protein A accumulation at the site of damage. Thus, non-targeted rearrangements reflect nuclear organization whereas DNA break formation governs the location and frequency of recurrent translocations, including those driving B-cell malignancies.     

Network Visualization in Cell Biology

Many of the processes known to take place in biological cells are analyzed in the form of different types of network.The complexity of these networks increases along with our knowledge of these processes,making their analysis more difficult.Network visualization is a powerful analysis method that will have to be developed further to deal with this complexity.This survey provides a brief overview of network visualization in general,followed by an in-depth discussion of its application to three network types specific to cell biology,namely gene regulatory,protein interaction,and metabolic networks.Finally,we discuss the difficulty of visually integrating these network types and trying to compare networks of cells that belong to different organisms.     

Adhesion and aggregation of human platelets to rabbit subendothelium. A new approach for investigation: Specific antibodies

Summary An IgG antibody occurring in a recently transfused thrombasthenic patient inhibited all the ADP-mediated aggregations and platelet-platelet interaction (thrombus formation) on rabbit aorta subendothelium; another IgG antibody occurring in a multitransfused Bernard-Soulier patient inhibited ristocetin and bovine factor VIII mediated aggregation and platelet-subendothelium interaction.