Human salmonellosis transmitted by a domestic turtle.

Salmonella typhimurium was isolated in the culture test of a small child admitted to hospital suffering from febrile gastroenteritis with stools containing traces of mucus and blood. Her mother also resulted positive for this microorganism. The family had recently bought a small turtle, imported from Florida, at the city fair. Further tests revealed Salmonella typhimurium in both the turtle's feces and the water in its tank.

Glycyrrhizic acid inhibits influenza virus growth in embryonated eggs.

Glycyrrhizic acid, at doses well tolerated by the cells in monolayer cultures, inhibited the recovery of hemagglutinins from both Influenza and Newcastle Disease virus-infected embryonated hen eggs. Since the drug had no effect on viral viability and did not impair the hemagglutinating activity of the virions, the growth of viruses into the embryo tissues might be mainly affected. Late viral replication steps, rather than the early ones, appeared to be involved in the inhibitory effect of glycyrrhizic acid.

Alpha-naphthyl acetate esterase activity in mouse thymus and other lymphoid organs.

Alpha-naphthyl acetate esterase (ANAE) reaction of mouse and rat thymus cells was studied. The majority of cells demonstrated ANAE in the form of multiple scattered granules. A reaction of this type appeared particularly labile, was found only when smears were fixed in formalin vapours and was inhibited by NaF. ANAE staining of thymus cells from mice of different ages was studied: the percentage of cells with single-spotted ANAE reaction was found to increase with age, while cells with granular scattered activity showed a progressive slight decrease. The percentage of ANAE positive cells in spleen appeared to be lower than in thymus, and showed only minor variations in different ages. In mouse and rat thymus and bowel lamina propria clusters of lymphocytes were found showing a sickle-shaped ANAE reaction, surrounding diffusely stained large cells which, on the basis of cytochemistry and phagocytosis ability, could be identified as macrophages. Analogous cell clusters were found in human tonsils and adenoids. These cell clusters were found to be similar to those formed by Ia-positive interdigitating cells which have been previously observed in human thymus, tonsils and bowel. The role of these clusters in the education process of lymphocytes is discussed.

Alpha-naphthyl acetate esterase activity in human lymphocytes: distribution in lymphocyte subpopulations and in mitogen-activated cells.

The cytochemical demonstration of nonspecific alpha-naphthyl acetate esterase (ANAE) activity in human peripheral blood mononuclear cells was studied. Different staining patterns were found, allowing differentiation of mononuclear cells into macrophages (strong granular cytoplasmic activity), B lymphocytes (negative reaction), Tgamma lymphocytes, i.e. bearing IgG Fc receptors (granular scattered reaction), and T non-gamma lymphocytes, i.e. devoid of IgG Fc receptors (single cytoplasmic ANAE spot). During the early phases of phytohaemagglutinin (PHA)- and concanavalin A (Con A)-induced activation, the reactivity of most lymphocytes became granular and scattered, similar to that found in Tgamma cells. Blast cells generating in successive phases appeared devoid of detectable enzymatic activity. The hypothesis is put forth that T cells showing granular, scattered reactivity represent a population of activated cells and that the redistribution of enzymatic activity could represent a preliminary step leading to secretion (lymphokine-like?) of enzyme from cytoplasm in the course of cell activation.