Ketosis, the metabolic response to energy crisis, is a mechanism to sustain life by altering oxidative fuel selection. Often overlooked for its metabolic potential, ketosis is poorly understood outside of starvation or diabetic crisis. Thus, we studied the biochemical advantages of ketosis in humans using a ketone ester-based form of nutrition without the unwanted milieu of endogenous ketone bo...

The mode of action of "terramycin" (oxytetracycline, Pfizer), has not been described in detail, although numerous investigators have shown that the antibiotic exerts an inhibitory effect on oxidative mechanisms. Terramycin inhibition of the oxidation of Krebs cycle intermediates by Escherichia coli was rieported by Wong and Ajl (1953). Similarly, Ajl (1953) observed the terramycin inhibition of...

Gene expression in response to Fe deficiency was analyzed in Arabidopsis roots and shoots through the use of a cDNA collection representing at least 6,000 individual gene sequences. Arabidopsis seedlings were grown 1, 3, and 7 d in the absence of Fe, and gene expression in roots and shoots was investigated. Following confirmation of data and normalization methods, expression of several sequence...

Sections from mucosal strips and rings of rat jejunum were studied with the light microscope and the electron microscope before and after incubation in a modified Krebs bicarbonate Ringer. Various additions were made to the incubation medium, and their effects on both the structure and the respiratory activity of the mucosal tissue were noted. In those cases in which an amino acid mixture was a...

We have studied the effects of bilirubin on respiration, respiratory control, oxidative phosphorylation, and swelling of mitochondria from rat liver, bovine heart, and brain of chick, rabbit, and monkey. Low (<4!0 PM) concentrations of bilirubin increase and high concentrations (>50 PM) decrease the respiration of liver or heart mitochondria. This biphasic effect is not observed in brain mitoch...

[In the course of studies of the inicorporation of adenine-8-C14 into the nucleic acids of Chlorella vtilgaris we observed an unexpectedly large formation of C'402 by the cultures in the dark. \When the oxidation of adenine in this system wvas followed manometrically, it was found that Up to 10 or 20 times more oxygen was taken up by the cells than could be accounted for by assuming the conmple...

Sections from mucosal strips and rings of rat jejunum were studied with the light microscope and the electron microscope before and after incubation in a modified Krebs bicarbonate Ringer. Various additions were made to the incubation medium, and their effects on both the structure and the respiratory activity of the mucosal tissue were noted. In those cases in which an amino acid mixture was a...

Damage to renal tubular and mesangial cells is central to the development of diabetic nephropathy (DN), a complication of diabetes which can lead to renal failure. Mitochondria are the site of cellular respiration and produce energy in the form of ATP via oxidative phosphorylation, and mitochondrial dysfunction has been implicated in DN. Since the kidney is an organ with high bioenergetic needs...

Chronic fatigue syndrome (CFS) is a highly debilitating disease of unknown aetiology. Abnormalities in bioenergetic function have been cited as one possible cause for CFS. Preliminary studies were performed to investigate cellular bioenergetic abnormalities in CFS patients. A series of assays were conducted using peripheral blood mononuclear cells (PBMCs) from CFS patients and healthy controls....

The division of Tetrahymena pyriformis GL cells was synchronized with either seven hypoxic or five hyperthermic (heat) shocks. Hyperthermic shocks of 34 degrees C produced no reduction in respiration rate and only a 19% decline in intracellular ATP concentration. Hypoxic shocks of 0.15% ambient oxygen concentration depressed intracellular ATP concentration 50%. It therefore appears that hypoxic...