This study investigated whether dichloroacetate (DCA) decreases the reliance on substrate level phosphorylation during the transition from rest to moderate-intensity exercise in humans. Nine subjects cycled at ∼65% of maximal oxygen uptake (V˙o 2 max) after a saline or DCA (100 mg/kg body wt) infusion, with muscle biopsies taken at rest and at 30 s and 2 and 10 min of exercise. DCA infusion inc...

The purpose of this study was to investigate the role of osteopontin (OPN) in diabetic hearts. Diabetes was induced in wild-type (WT) and OPN knockout (KO) mice by using streptozotocin (150 mg/kg) injection. Left ventricular (LV) structural and functional remodeling was studied 30 and 60 days after induction of diabetes. Induction of diabetes increased OPN expression in cardiac myocytes. Heart ...

Creatine kinase (CK) forms a small family of isoenzymes playing an important role in maintaining the concentration of ATP and ADP in muscle cells. To delineate the impact of a lack of CK activity, we studied contractile performance during a single maximal tetanic contraction and during 12 repeated tetanic contractions of intact dorsal flexors of CK knockout (CK(-/-)) mice. To investigate the ef...

We have developed a method that can measure high-energy phosphate metabolite concentrations in humans with 1D resolved surface-coil NMR spectroscopy. The metabolites are measured by phosphorus (31P) NMR spectroscopy, and the tissue water proton (1H) resonance from the same volume serves as an internal concentration reference. The method requires only the additional acquisition of a 1H data set,...

BACKGROUND AND PURPOSE Membrane lipid degradation plays an important role in the pathogenesis of ischemic brain damage, but there is little information on changes in cerebrosides, sulfatides, and sphingomyelin. We studied regional changes in the quantities of these lipids during complete global brain ischemia in rats. METHODS Nitrous oxide-anesthetized rats were subjected to ischemia by a hig...

A low concentration of hyaluronan (HA) in lymph compared with tissue suggests a large bound fraction. To investigate the distribution and mobility of HA and serum albumin (Alb), we eluted the rat tail tendon with a series of l5 successive centrifugations, each preceded by the addition of 0.15 M NaCl (15% of initial wet wt). The eluate concentration fell exponentially versus the accumulated elua...

The neonatal mammal requires especially large amounts of choline to sustain growth. Much of this choline is derived from the newborn's only source of food, milk. The concentration of choline in rat milk [182 +/- 24 microM (S.E.M.)] was much higher than that in maternal serum (11.6 +/- 0.9 microM), suggesting that a mechanism capable of concentrating choline into milk must exist. We characterize...

Organochlorine contaminants (OCs) and stable isotopes of carbon (δ13C) and nitrogen (δ15N) were determined in 7 benthic and 7 pelagic marine invertebrate species from the North American Arctic to identify factors influencing OC concentrations. Values of δ13C separated benthic (enriched in 13C) from pelagic species and δ15N values gave a logical approximation of trophic level (TL). With few exce...

Food consumption is an important route of human exposure to organochlorines (OCs). In order to assess the potential health risks associated with these contaminants due to fish consumption, five species of fish were collected from a local market in Zhoushan City, an island in the East China Sea. Dioxin-like compounds, such as polychlorinated dibenzo-p-dioxins/ dibenzofurans, in the fish samples ...