Trends in incidence of AIDS associated with transfusion of blood and blood products in Europe and the United States, 1985-93.

OBJECTIVE--To quantify patterns and trends in incidence of AIDS associated with transfusion of blood and its products in 14 European countries and the United States. DESIGN--Data were derived from the World Health Organisation''s European non-aggregate AIDS dataset and, for the United States, from the Centers for Disease Control AIDS public information dataset. Rates were standardised by using the world standard populations and adjusted for reporting delays in each country. SUBJECTS--Cases of AIDS in patients with haemophilia and recipients of transfusions. RESULTS--Overall, between 1985 and 1993 almost 6000 cases of AIDS associated with transfusions were registered in the 14 European countries considered and over 8000 in the United States between 1985 and 1992. Most European countries had annual age adjusted rates lower than 0.5 per million children aged 12 or less and between 1 and 2 per million adults. The United States had rates around 1 per million children and 5 per million adults in the most recent period. For children, the highest rates were generally reached in 1985-7, whereas in adults the highest rates were in the late 1980s. France had the highest overall incidence of AIDS related to transfusion in Europe (3.3 per million). Romania had a major epidemic in children (over 30 cases per million children in 1988-90). Incidence rates of AIDS associated with transfusion were still increasing in some southern European countries in the early 1990s. CONCLUSIONS--Apart from in France and Romania it is clear that rates of bloodborne AIDS in European countries are lower than those registered in the United States.     

Contrasting effects of stimulation of the caudate nucleus and globus pallidus on paroxysmal hippocampal activity in the cat

The different actions exerted by pallidum and caudate nucleus on electrically induced epileptic activity of hippocampus were analyzed. Caudate appeared to inhibit hippocampal after discharges duration (HAD) while the globus pallidus exerted a facilitatory effect on HAD duration. Both effects were maximal when conditioning stimulation immediately preceded hippocampal test stimulation. The results are discussed considering reciprocal functional connections of the two striatal structures.     

The cytoplasmic coatomer protein COPI. A potential translational regulator.

Expression of the asialoglycoprotein receptor (ASGR) by the human hepatocellular carcinoma cell lines HepG2 and HuH-7 in response to intracellular cGMP concentrations was previously shown to be regulated at the translational level (1). Stable transfection of COS-7 cells with deletion constructs encoding the asialoglycoprotein receptor H2b subunit localized the cGMP-responsive cis-acting element to the mRNA 5'-untranslated region. Resolution by anion exchange chromatography of an S-100 isolated from human liver resulted in the partial purification of an RNA-binding protein specific to this cis-acting element. Northwestern analysis using the 5'-untranslated region as probe indicated that a 140-kDa protein was the potential RNA-binding protein. Sequence of tryptic peptides suggested that the 140-kDa protein was the alpha-COP subunit of coatomer protein COPI, usually associated with trans-Golgi network membrane traffic. Immunoblot analysis confirmed the presence of alpha-COP in the Mono-Q fraction as well as that of a second coatomer subunit, beta-COP. Antibody induced gel retardation supershift confirmed the identification of the RNA-binding proteins as alpha- and beta-COP. Although the RNA recognition motif appears to reside solely in alpha-COP, antibody-induced supershift strongly indicated that the entire coatomer complex was the trans-acting factor. Depletion of S-100 with the antibody to beta-COP confirmed that the coatomer was the sole protein binding to the ASGR mRNA 5'-untranslated region in liver cytosol and responsible for inhibition of in vitro translation of the asialoglycoprotein receptor.     

Horse heart myoglobin reconstituted with a symmetrical heme. A circular dichroism study

Proton NMR studies on myoglobins and hemoglobins reconstituted with non-natural hemes, possessing different side chains in the pyrrolic rings, have provided interesting information for the understanding of the mechanism governing heme reorientation in the globin pocket, during synthesis of the native protein in vivo or in the reconstitution process in vitro. More recently, circular dichroism (CD) studies have been reported as a qualitative, alternative tool, with respect to 1H-NMR for detecting heme disorder in a reconstituted myoglobin or hemoglobin. In this paper, a CD study is reported on the reconstitution of horse heart myoglobin with protoheme XIII, a heme possessing true rotational symmetry about its alpha, gamma-meso axis. The results obtained show that the reconstitution product with this heme, which binds to the apoprotein with high affinity, not dissimilar from that of the natural heme, is characterized by a CD spectrum with bands possessing rotational strengths much lower than in the native protein. Furthermore, the CD changes detected as a function of time, during heme reorientation, in the case of natural heme, are absent when the apoprotein is reconstituted with protoheme XIII. These data provide independent evidence for reorientation of the natural heme, which follows its insertion into the protein matrix.     

DNA repair in cultured mouse cells of increasing population doubling level

Cultures of mouse cells of various population doubling levels (PDL) were examined for DNA-repair capabilities as estimated by (i) the excision of pyrimidine dimers; (ii) unscheduled DNA synthesis (UDS) in response to UV-irradiation or N-methyl-N'-nitrosoguanidine (MNNG) treatment; (iii) the levels of two DNA-repair enzyme activities, uracil DNA glycosylase and AP endonuclease. The responses to ultraviolet light and MNNG decreased rapidly within the first two PDL and more slowly thereafter until essentially no repair was detected by PDL 12. A continuous cell line which emerged from the cultured cells after a crises period had some restoration of repair capability. The amount of uracil DNA glycosylase activity decreased by approximately 40% before the crises period then decreased by 90% in the continuous cell line. In contrast, the amount of AP endonuclease activity present in the precrises cells showed no significant change until PDL 12, then increased 6-7-fold in the continuous cell line.