Depsidone constituents from the quintaria group of Nephroma species

A new lichen depsidone was isolated, in the form of its triacetate derivative from the acetylated extracts of Nephroma antarcticum and has been demonstrated to be hypoconstictic acid-triacetate. Two related depsidones, hypostictic acid hyposalazinic acid, were isolated from N. australe.     

Individual variation of nucleoside triphosphate pyrophosphohydrolase activity in human erythrocytes,granulocytes, lymphocytes,and platelets

Analysis of the nucleoside triphosphate pyrophosphohydrolase specific activity of red cells obtained from a random Caucasian population indicated at least two subclasses. The specific activity of 18% of the population ranged from undetectable activity to 27.5 nmol ITP cleaved/20 min/mg hemoglobin. The remainder of the population had higher activity, 27.5–125 nmoles ITP cleaved/20 min/mg hemoglobin. The variation of NTPH activity evident in the red cells of an individual is reflected in granulocytes, lymphocytes, and platelets of that individual. Erythrocyte activity ranges from 0.7 to 21 units (nmol of ITP cleaved in 20 min)/10⁷ cells, granulocytes have 17–201 units/10⁷ cells, lymphocytes have 91–462 units/10⁷ cells, and platelets have 1.1–7.1 units/10⁷ platelets. These cell differences are discussed with respect to the hypothesis that NTPH prevents incorporation of ITP or dITP into nucleic acids.This work was supported by funds allocated by the Agricultural Experiment Station, Michigan State University. Michigan Agricultural Experiment Station Journal No. 8727.     

Bubble flow in the downflow section of an airlift tower

Characterization of the two-phase flow in the downflow section of the airlift tower is necessary for accurate modeling of the airlift tower. A Split-cylinder airlift tower was investigated for superficial gas velocities ranging from 0.0683 to 0.3315 m/sec for an air–water system. Statistical cross-covariance techniques were used to yield velocities, void fractions, and flow rates corresponding to upward and downward components of bubble flow in the downflow section of the airlift tower. From these results the fraction of incoming air entrained in the downflow section was determined as a function of superficial gas velocity and position.     

Congruency of phylogenies derived from different proteins

Summary This communication examines the question of phylogenetic congruency- i.e., whether or not the branching order of evolutionary trees is independent of the protein studied. It was found that trees constructed for birds on the basis of immunological comparison of their transferrins, albumins, and ovalbumins agree approximately with a published tree based on the amino acid sequences of their lysozymesc. This congruency is especially noteworthy with respect to the phylogenetic position of the chachalaca, a Mexican bird classified on morphological grounds in the family Cracidae of the order Galliformes. At the protein level, this species differs as much from non-cracid galliform birds as does the duck, which belongs to another order. Despite the organismal similarity between cracid and non-cracid galliform birds, the molecular relationship is remote. If this contrast between organismal and molecular results had been based on comparative studies with only lysozyme, one could have ascribed the contrast to the possibility that chachalaca lysozyme was paralogous, rather than orthologous, to the other bird lysozymesc. Examination of several proteins is thus desirable in cases of possible paralogy.This work was supported in part by grants GB-42028X from NSF and GM-21509 from NIH     

Enhanced synthesis de novo of phosphatidylinositol in lymphocytes treated with cationic amphiphilic drugs.

A variety of amphiphilic cations caused very large increases in the rates of incorporation of Pi and glycerol into phosphatidylinositol in pig mesenteric small lymphocytes. This synthesis de novo of phosphatidylinositol led to a doubling of the phosphatidylinositol concentration in the cells within 3.5 h. The increase in synthesis of phosphatidylinositol labelled with [3H]- or [14C]-glycerol was matched by an approximately equivalent decrease in incorporation of glycerol into phosphatidylcholine, phosphatidylethanolamine and triacylglycerol. Amphilic cations which produced these effects included, in order of decreasing effectiveness, trifluoperazine (half-maximal effect at about 70 mum) greater than chlorpromazine approximately promethazine approximately imipramine greater than cinchocaine greater than amethocaine approximately cetyltrimethylammonium greater than fenfluramine greater than amphetamine greater than 2-phenethylamine greater than cocaine approximately procaine; the most effective compounds were those with the largest and most hydrophobic non-polar substituents. The response to cations was not changed by varying the extracellular Ca2+ concentration in the range 10 nm-1mm. The active amphiphilic cations interacted with anionic phospholipids causing aggregation of aqueous dispersions and/or changes in chromatographic behaviour. These results indicate that amphiphilic cations redirect glycerolipid synthesis de novo, probably owing to inhibition of phosphatidate phosphohydrolase, so that phosphatidylinositol synthesis is increased at the expense of other glycerolipids.     

Immune Complexes in Cystic Fibrosis

Circulating immune complexes were detected in serum and sputum of patients with cystic fibrosis (C.F.). There were extensive deposits of immunoglobulins and complement immune complexes in several of the C.F. organs, especially the respiratory and gastrointestinal tracts, but not in the kidneys. Significant concentrations of IgG and of complement complexes could be eluted from the lungs of the C.F. patients but not from those of controls. Studies involving immunoabsorption, autoradiography, and molecular sieving through Sephadex G-200 columns identified both bovine serum albumin and staphylococcal α-haemolysin as two of the antigens present in the immune complexes. The sedimentation constant of the immune complexes was about 8S to 11S. The clinical significance of these immune complexes and the wide variety of antibodies detected in C.F. patients are discussed.