Recombination and clonal propagation in different populations of the lichen Lobaria pulmonaria.

Propagation, dispersal, and establishment are fundamental population processes, and are critical stages in the life cycle of an organism. In symbiotic organisms such as lichens, consisting of a fungus and a population of photobionts, reproduction is a complex process. Although many lichens are able to reproduce both sexually and asexually, the extent of vegetative propagation within local populations is unknown.

T-Cell immune activation in children with vertically transmitted hepatitis C virus infection.

Little is known concerning the clinical features, the histological outcome, and the effects on the maturation of immune system of children with vertically-transmitted hepatitis C virus (HCV) infection. Specifically, no data are available on the peripheral distribution of T-cell subsets. The frequency of naive and memory cells, activated T cells, and cytokine-producing T cells was analyzed in nine HCV-infected children born to HCV-positive mothers.

T cell responses to highly active antiretroviral therapy defined by chemokine receptors expression, cytokine production, T cell receptor repertoire and anti-HIV T-lymphocyte activity.

The immunological correlates of highly active antiretroviral therapy (HAART)-induced suppression of human immunodeficiency virus type 1 (HIV-1) replication have been investigated. 20 HIV-1-infected patients with mean CD4+ T cell count of 298/microl, plasma viral load of 4.7 log10 copies/ml and naive for protease inhibitors (PI) were studied during12 months of HAART.

Subtype-selective positive cooperative interactions between brucine analogues and acetylcholine at muscarinic receptors: radioligand binding studies.

We studied the interactions of strychnine, brucine, and three of the N-substituted analogues of brucine with [3H]N-methylscopolamine (NMS) and unlabeled acetylcholine at m1-m5 muscarinic receptors using equilibrium and nonequilibrium radioligand binding studies. The results were consistent with a ternary allosteric model in which both the primary and allosteric ligands bind simultaneously to the receptor and modify the affinities of each other. The compounds had Kd values in the submillimolar range, inhibited [3H]NMS dissociation, and showed various patterns of positive, neutral, and negative cooperativity with [3H]NMS and acetylcholine, but there was no predictive relationship between the effects.