CTLA4 Autoimmunity-Associated Genotype Contributes to Severe Pulmonary Tuberculosis in an African Population

The gene of Cytotoxic T Lymphocyte-associated Antigen 4 (CTLA4), a negative regulator of T lymphocytes, contains a single-nucleotide polymorphism (SNP) at position +6230A->G (ct60A->G), which has been found associated with several autoimmune diseases and appears to reduce T-cell inhibitory activity. In Ghana, West Africa, we compared the frequencies of CTLA4 +6230 A/G and 6 haplotype-tagging SNPs in 2010 smear-positive, HIV-negative patients with pulmonary tuberculosis (TB) and 2346 controls matched for age, gender and ethnicity. We found no difference in allele frequencies between cases and controls. However, +6230A and a distinct CTLA4 haplotype and a diplotype comprising the +6230A allele were significantly less frequent among cases with large opacities in chest radiographs compared to those with small ones (P_{corrected [cor]} = 0.002, P_cor = 0.00045, P = 0.0005, respectively). This finding suggests that an increased T-cell activity associated with the CTLA4 +6230G allele contributes to pathology rather than to protection in pulmonary TB.     

In situ nick translation of metaphase chromosomes with biotin-labeled d-UTP

Summary Conditioned culture medium from Daudi cells was used as a source of soluble H-Y antigen. Concentrated culture medium was labeled with ¹²⁵I and then fractionated by gel filtration. Column fractions were assayed for the presence of H-Y antigen by urease-ELISA. H-Y antigen-containing fractions were then pooled and subjected to an improved immunoprecipitation protocol. Three predominant H-Y antigenic proteins were identified with estimated molecular weights of above 200,000, 50,000, and 20,000.     

UDP-N-acetylglucosamine 1-carboxyvinyl-transferase from Acinetobacter calcoaceticus

Abstract We have analyzed the sequence downstream of rpoN from Zcinetobacter calcoaceticus and identified an open reading frame encoding a protein with high similarity to UDP- N -acetylgucosamine 1-carboxyvinyl-transferase (MurZ). Multicopy plasmids encoding this enzyme conferred phosphomycin resistance to A. calcoaceticus . The polar effect of a rpoN mutation on the phosphomycin resistance level suggests that murZ is, in part, cotranscribed with rpoN . These observations confirm that A. calcoaceticus represents the first exceptin from a conserved genetic context of rpoN observed in several other Gram-negative bacteria.     

Quantification of two viruses in technical preparations of Orgyia pseudotsugata baculovirus by means of buoyant density centrifugation of viral deoxyribonucleic acid.

A reliable method was developed for the quantitative determination of two nuclear polyhcdrosis viruses present in commercially prepared viral insecticides used against Orgyia pseudotsugata. Deoxyribonucleic acids, from nuclear polyhedrosis bundle virus and nuclear polyhedrosis single-rod virus, were separated on CsCl gradients according to their respective buoyant densities, 1.715 and 1.704 g/ml. The proportions of the two viruses were quantified by measuring the relative absorbance at 254 nm of their deoxyribonucleic acid peaks.     

No evidence for linkage of autosomal dominant proximal spinal muscular atrophies to chromosome 5q markers

Summary Two recent articles have reported the linkage of a gene for recessive spinal muscular atrophy (SMA) on the chromosome region 5q11.2–13.3. Our data show no linkage of the dominantly inherited forms of SMA to this chromosome region.     

Accumulation of cadmium by immobilizedZoogloea ramigera 115

Summary Zoogloea ramigera 115 was immobilized into beads of calcium-alginate and placed into batch air-bubbled column reactors. In the absence of any added nutrients the immobilized bacterium adsorbed Cd from solutions containing levels of 2 and 20 g ml^–1 per day, over a period of 21 and 20 days, respectively. Adsorption of Cd from solutions containing 20 g ml^–1 Cd was better than 90% for 16 days. Beads treated with Cd at 2 g ml^–1 never adsorbed less than 95% of the metal. Alginate adsorbed Cd as well, but inclusion of cells changed the effectiveness of adsorption. Of a 250 g ml^–1 Cd solution, alginate adsorbed 70.4% Cd in 60 min whereas alginate plus cells adsorbed 90.5% in the same time span. Temperature had no effect on adsorption by immobilized cells at levels of 2 and 10 g ml^–1 Cd. However at higher concentrations, binding was enhanced as temperature increased.Z. ramigera beads were stable during all treatments and for prolonged periods of time (21 days).     

Long lasting anti-adrenergic effect of 7-oxo-prostacyclin in the heart: a cycloheximide sensitive increase of phosphodiesterase isoform I and IV activities

Evidence is accumulating that 7-oxo-prostacyclin (7-oxo-PGI₂) induces a delayed indirect anti-adrenergic and cytoprotective effect on the myocardium, the mechanism of which is still unclear. To demonstrate that a single application of 7-oxo-PGI₂ (50 g/kg i.m.) 48 h prior to starting experiments attenuates the isoprenaline inducible inotropic response and accumulation of cAMP, isolated hearts of pretreated animals were perfused in the Langendorff mode with and without isoprenaline (1 to 100 nM). The late anti-adrenergic effect of the drug was manifested by a significant attenuation in the elevation of cAMP levels as well as in contractile force development. This effect was not due to changes in cAMP generation as there were identical ₁-adrenoceptor densities and affinities (as calculated from [³H]-CGP binding studies), G_i and G_s protein patterns (as taken from Western blots) as well as adenylyl cyclase activity measurements in the hearts studied. The anti-adrenergic potency of 7-oxo-PGI₂, however, was found to be related to a significant rise in cyclic nucleotide hydrolysis by phosphodiesterase (PDE). Using the fast-performance liquid chromatographic separation for PDE isoforms, a significant increase in the activity of PDE isoforms I and IV (260±28 vs 110±12 pmol cGMP/min x enzyme fraction and 77±11 vs 34±3 pmol cAMP/min x enzyme fraction, respectively) was found in the solubilized fraction of cardiac membranes in comparison to untreated controls; PDE IV activity was also increased in the cytosolic fraction (106±14 vs 65±6 pmol cAMP/min x enzyme fraction). The hypothesis that the delayed anti-adrenergic effect of 7-oxo-PGI₂ is initiated by an induction and accelerated synthesis of PDE I and IV in the heart is underlined by the fact that cycloheximide suppresses completely both the rise in PDE activities and the anti-adrenergic effects studied. It is suggested that an inducible predominance of cAMP degradation over its generation may be of relevance in processes related to heart protection.