Measuring the production of marine phytoplankton

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Rational Design of Sequestering Agents for Plutonium and Other Actinides

Trace element reference values in tissues from inhabitants of the European community. I. A study of 46 elements in urine, blood and serum of Italian subjects.

Past studies have shown that serum-free cultures of PC12 cells are a useful model system for studying the neuronal cell death which occurs after neurotrophic factor deprivation. In this experimental paradigm, nerve growth factor (NGF) rescues the cells from death. It is reported here that serum-deprived PC12 cells manifest an endonuclease activity that leads to internucleosomal cleavage of their cellular DNA. This activity is detected within 3 h of serum withdrawal and several hours before any morphological sign of cell degeneration or death. NGF and serum, which promote survival of the cells, inhibit the DNA fragmentation. Aurintricarboxylic acid (ATA), a general inhibitor of nucleases in vitro, suppresses the endonuclease activity and promotes long-term survival of PC12 cells in serum-free cultures. This effect appears to be independent of macromolecular synthesis. In addition, ATA promotes long-term survival of cultured sympathetic neurons after NGF withdrawal. ATA neither promotes nor maintains neurite outgrowth. It is hypothesized that the activation of an endogenous endonuclease could be responsible for neuronal cell death after neurotrophic factor deprivation and that growth factors could promote survival by leading to inhibition of constitutively present endonucleases.

https://rupress.org/jcb/article-pdf/115/2/461/1061989/461.pdf

Aurintricarboxylic acid rescues PC12 cells and sympathetic neurons from cell death caused by nerve growth factor deprivation: correlation with suppression of endonuclease activity.

https://www.onlinelibrary.wiley.com/doi/pdf/10.1002/jps.2600570601

The binding of drugs by plasma proteins.

Stability of Alkaline Earth—Organic Acid Complexes Measured by Ion Exchange1

The inhibition and recovery of liver cytochrome oxidase in mice, rats and gerbils were measured after the i.p. administration of potassium cyanide. The inhibition of cytochrome oxidase reached a maximum 5 to 10 min after cyanide administration, and in the mouse returned to normal activity 5 to 20 mm later, depending on dose. However, in the rat and gerbil, recovery of the enzyme after maximal inhibition was more prolonged, and, depending on dose and strain of animal, required up to 1 hr or more. Also studied were the effects of varying doses of sodium thiosulfate and sodium nitrite, given prior to or after cyanide administration, in modifying the syndrome of cyanide poisoning and accelerating the reactivation in vivo of cytochrome oxidase. Thiosulfate and nitrite were within minutes able to reactivate in vivo cyanide-induced inhibition of cytochrome oxidase when administered before or after cyanide. These drugs prevented the symptoms or lethality of cyanide when given even 1 or 2 hr prior to cyanide administration, depending on the species treated. The inhibition in spleen cytochrome oxidase by cyanide and its reversal by thiosulfate are similar to those of the liver except that the effects are somewhat slower. The ability of animals to survive divided doses of cyanide depended on the time between doses. If the second dose was administered at a time when the inhibition of cytochrome oxidase was at or near a maximum, the animals died even though the total dose when given at one time was sublethal. It appears that thiosulfate acts by penetrating the mitochondria where it furnishes sulfur to rhodanese, whereas nitrite acts extramitochondrially. The prophylactic and therapeutic actions of thiosulfate appear more effective than heretofore considered, especially relative to nitrite. This observation has important implications for treatment of cyanide poisoning in humans.

Jack Schubert

Papers

Stability of Alkaline Earth—Organic Acid Complexes Measured by Ion Exchange1

Antagonism of experimental cyanide toxicity in relation to the in vivo acitivity of cytochrome oxidase.

Rapid Wet Combustion Method for Carbon Determination

Complexes of alkaline earth cations including radium with amino acids and related compounds

Catalytic activity of metal chelates and mixed-ligand complexes in the neutral pH region. II. Copper-histidine