Sub-lethal autolysis : Modification of cell periphery by lysosomal enzymes

Lysosomal activation was induced in dog kidney and HEp-2 cells by treatment with anticellular serum and high concentrations (20 μg/ml) of vitamin A alcohol. The morphological changes accompanying the release of enzymes from activated lysosomes were described. Measurements of cell coat thickness by ellipsometry revealed that lysosomal enzymes released extracellularly were able to digest the coat. The scale of enzyme release was an important factor in determining the amount of coat digested. Complement-sufficient anticellular sera and high concentrations of vitamin A induced marked lysosomal activation and extensive digestion of the coat. Complement-deficient anticellular serum produced significantly less lysosomal labilization and only limited digestion of the coat. The digestion of the cell coat induced by these agents was prevented by pretreatment of the cells with either hydrocortisone or chloroquine.     

Fluorinated carbohydrates : Part XIII. 2-deoxy-2-fluoro-D-galactose

Reaction of trifluoro(fluoroxy)methane at ca. −80° with 3,4,6-tri-O-acetyl-D-galactal affords trifluoromethyl 3,4,6-tri-O-acetyl-2-deoxy-2-fluoro-α-D-galactopyranoside (2, 39%), 3,4,6-tri-O-acetyl-2-deoxy-2-fluoro-α-D-galactopyranosyl fluoride (3, 37%), trifluoromethyl 3,4,6-tri-O-acetyl-2-deoxy-2-fluoro-α-D-talopyranoside (4, 3%), and 3,4,6-tri-O-acetyl-2-deoxy-2-fluor-α-D-talopyranosyl fluoride (5, 2%). The structures of compounds 2–5 have been established by n.m.r. spectroscopy. Acid hydrolysis of 2 or 3 allords 2-deoxy-2-fluoro-D-galactose.     

Light scattering by cellulose : IV. Fibers with helical morphology

Solid-state light scattering has been used to study the scattering by the helically wound microfibrils in wood fibers. Scattering envelopes have been recorded from a section of Eastern spruce wood as well as a single fiber of Black spruce. Theoretical expressions for the intensity of light scattered by a continuous helix have been derived and found to be in fair agreement with the experimental results. A method of estimating the “pitch” and “tilt” of the helical segments is outlined.     

Heterocycles from saccharide hydrazones : Part I. Saccharide 1,3,4-oxadiazoles

Oxidation, with iodine-mercuric oxide, of acetylated saccharide aroylhydrazones and of aromatic aldehyde hydrazones yields 5-aryl-2-(polyacetoxyalkyl)-1,3,4-oxadiazoles and 2,5-diaryl-1,3,4-oxadiazoles, respectively. On de-O-acetylation, saccharide oxadiazole acetates rearrange to the tautomeric, cyclic iminolactones which, on reacetylation, regenerate the starting oxadiazoles. Attempted dehydration of saccharide acetyl- and benzoyl-hydrazones by treatment with boiling acetic anhydride under reflux resulted in the formation of peracetylated N,N-diacetylhydrazones and-N-acetyl-N-benzoylhydrazones, respectively.     

Quinacrine fluorescence of metaphase chromosomes : Identical patterns in different tissues

The quinacrine mustard fluorescence patterns of the metaphase chromosomes of different tissues of the same plant species were found to be identical. Similar studies of the chromosome regions on human material gave the same result.     

Immobilization antigens of Tetrahymena pyriformis : I. Assay and extraction

A method using immunodiffusion has been established to assay the two mutually exclusive temperature dependent immobilization antigens, H and T, of Tetrahymena pyriformis. Specific antiserum was obtained by exploitation of allelic or temperature induced variations among inbred strains for absorption of antisera prepared against whole cells. The antigens were extracted both from isolated cilia and from whole cell bodies. Mild detergent extraction was found to be more efficient than mechanical disruption of the cells by freeze-thawing. The sedimentation behavior in sucrose density gradients of active H antigen was the same, whether freeze-thaw or detergent extracted; similarly, the sedimentation behavior of T was the same following the two extraction methods. Extraction with acetic acid, as reported by others, solubilized the same material as the detergent, but the acid denatured the antigen. An estimate of the molecular weight of the antigen of 29 000 for H and 23 000 for T was made.