Arteriovenous differences for acetoacetate, beta-hydroxybutyrate, glucose, lactic acid, and glutamine and other amino acids were measured across Morris hepatomas 5123C, 7777, and 7288CTCF and Walker sarcocarcinoma 256 in vivo in rats fasted for 2 days. The acetoacetate and beta-hydroxybutyrate concentrations in arterial whole blood of fasted tumor-bearing rats were 0.52 +/- 0.06 and 1.82 +/- 0....

Polyhydroxyalkanoates (PHAs) have been demonstrated to be a family of biopolymers with good biodegradability and biocompatibility. To mimic the real microenvironment of extracellular matrix (ECM) for cell growth, novel nanofiber matrices based on PHA polymers were prepared via a phase separation process. Three-dimensional interconnected fibrous networks were observed in these matrices with aver...

The effect of three-day fasting on cardiac ischemic tolerance was investigated in adult male Wistar rats. Anesthetized open-chest animals (pentobarbitone 60 mg/kg, i.p.) were subjected to 20-min left anterior descending coronary artery occlusion and 3-h reperfusion for infarct size determination. Ventricular arrhythmias were monitored during ischemia and at the beginning (3 min) of reperfusion....

Two autotrophic carbon fixation cycles have been identified in Crenarchaeota. The dicarboxylate/4-hydroxybutyrate cycle functions in anaerobic or microaerobic autotrophic members of the Thermoproteales and Desulfurococcales. The 3-hydroxypropionate/4-hydroxybutyrate cycle occurs in aerobic autotrophic Sulfolobales; a similar cycle may operate in autotrophic aerobic marine Crenarchaeota. Both cy...

Novel biodegradable poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [PHBV]/graphene nanocomposites were prepared by solution casting. The thermal properties, crystallization behavior, microstructure, and fracture morphology of the composites were investigated. Scanning electron microscope (SEM) results show that graphene layers are homogeneously dispersed in the polymer matrix. X-ray diffraction (...

Ilyobacter delafieldii produced an extracellular poly-[3-hydroxybutyrate (PHB) depolymerase when grown on PHB; activity was not detected in cultures grown on 3-hydroxybutyrate, crotonate, pyruvate or lactate. PHB depolymerase activity was largely associated with the PHB granules (supplied as growth substrate), and only 16 % was detected free in the culture supernatant. Monomeric 3-hydroxybutyra...

Freshly isolated Morris Hepatoma 7777 cells were prepared for a study of the utilization of palmitate and beta-hydroxybutyrate as metabolic fuels compared to other major energy substrates (glucose and glutamine). These cells were capable of oxidizing both [U-14C]palmitate and beta-[3-14C]hydroxybutyrate although the rates accounted for only 10 +/- 3 (SD) and 9 +/- 4% of total oxygen consumed, r...