Serum trace element levels in HIV-infected subjects.

The absolute number of T4 cells and the serum concentrations of Ca, Cu, Fe, K, Mg, P, Se, and Zn were determined in 59 Walter-Reed staged, HIV-infected men, compared to healthy controls, serum levels of Ca, Cu, and Fe were significantly higher, those of P and Se significantly lower in the HIV-infected subjects. In the HIV-infected cases, but not in the controls, the concentrations of Se and Zn, of Ca with Cu and Fe, and of Fe with P, were directly correlated. In the controls, the correlation between the levels of K and Mg was direct, and inverse between those of Zn and P. Trace element levels did not significantly correlate with WR-stage. However, the absolute number of T4 cells was directly correlated with the serum Mg concentration.

[Trace element concentrations in HIV infected patients]. / Spurenelementkonzentrationen bei HIV-Infizierten.

The serum concentrations of Ca, Cu, Fe, K, Mg, P, Se and Zn and the absolute number of T4 cells were determined in 59 HIV-infected men. Serum levels of Ca, Cu and Fe were significantly higher, those of P and Se significantly lower in the infected, compared to healthy controls. In the HIV-infected cases the concentrations of Se and Zn, of Ca with Cu and Fe, and of Fe with P, were directly correlated. In the controls, the correlation between the levels of K and Mg was direct, and inverse between those of Zn and P. WR-stage and trace element levels did not correlate. The absolute number of T4-lymphocytes was directly correlated with the serum Mg concentration.

Clinical course of subacute HIV encephalitis.

A subacute encephalitis is increasingly recognized to be the most frequent cerebral manifestation of human immunodeficiency virus (HIV) infection. Contradictory reports are given in the literature concerning its clinical course. In the present study, a group of 19 patients with subacute encephalitis was followed for an average of 210 days. A steady progression of the disease was documented using the Karnofsky index. An advanced disease, rated according to the Walther Reed staging classification, but not isolated immunological parameters such as the ratio of OKT4/8 subsets are associated with more rapid progression of the encephalitis. Age, social status, duration of HIV positivity and antibody titers to cytomegalovirus could not be identified as contributing factors.

Drastic rise of intracellular adenosine(5')tetraphospho(5')adenosine correlates with onset of DNA synthesis in eukaryotic cells.

An assay of adenosine(5')tetraphospho(5')adenosine (Ap4A), based on the luciferin/luciferase method for ATP measurement, was developed, which allows one to determine picomolar amounts of unlabeled Ap4A in cellular extracts. In eukaryotic cells this method yielded levels of Ap4A varying from 0.01 microM to 13 microM depending on the growth, cell cycle, transformation, and differentiation state of cells. After mitogenic stimulation of G1-arrested mouse 3T3 and baby hamster kidney fibroblasts the Ap4A pools gradually increased 1000-fold during progression through the G1 phase reaching maximum Ap4A concentrations of about 10 microM in the S phase. Quiescent 3T3 cells reach a high level of Ap4A (1 microM) in a 'committed' but prereplicative state if exposed to an external mitogenic stimulant (excess of serum) and simultaneously to a synchronizer which inhibits entry into the S phase (hydroxyurea). When the block for DNA replication was removed at varying times after removal of the stimulant decay of commitment to DNA synthesis was found correlated with a shrinkage of the Ap4A pool. Cells lacking a defined G1 phase (V79 lung fibroblasts, Physarum) possess a constitutively high base level of Ap4A (about 0.3 microM) even during mitosis. From this high level, Ap4A concentration increases only about tenfold during the S phase. Temperature-down-shift experiments, using chick embryo cells infected with transformation-defective temperature-sensitive viral mutants(td-ts), have shown that the expression of the transformed state at 35 degrees C is accompanied by a tenfold increase of the cellular Ap4A pool. Treatment of exponentially growing human cells with interferon leads, concomitantly with an inhibition of DNA syntheses, to a tenfold decrease in intracellular Ap4A levels within 20 h. The possibility of Ap4A being a 'second messenger' of cell cycle and proliferation control is discussed in the light of these results and those reported previously demonstrating that Ap4A is a ligand of mammalian DNA polymerase alpha, triggers DNA replication in quiescent mammalian cells and is active in priming DNA synthesis.