Kinetics

Over 1.5 billion people lack the skeletal muscle fast-twitch fibre protein α-actinin-3 due to homozygosity for a common null polymorphism (R577X) in the ACTN3 gene. α-Actinin-3 deficiency is detrimental to sprint performance in elite athletes and beneficial to endurance activities. In the human genome, it is very difficult to find single-gene loss-of-function variants that bear signatures of positive selection, yet intriguingly, the ACTN3 null variant has undergone strong positive selection during recent evolution, appearing to provide a survival advantage where food resources are scarce and climate is cold. We have previously demonstrated that α-actinin-3 deficiency in the Actn3 KO mouse results in a shift in fast-twitch fibres towards oxidative metabolism, which would be more "energy efficient" in famine, and beneficial to endurance performance. Prolonged exposure to cold can also induce changes in skeletal muscle similar to those observed with endurance training, and ch...

An extensive programme of experiments was conducted in the former USSR on transfer of radionuclides to a wide range of different agricultural animals. Only a few of these studies were made available in the English language literature or taken into account in international reviews of gastrointestinal uptake. The paper gives extended information on Russian research on radionuclide absorption in the gut of farm animals performed in controlled field and laboratory experiments from the 1960s to the current time. The data presented in the paper, together with English language values, will be used to provide recommended values of absorption specifically for farm animals within the revision of the IAEA Handbook of Parameter Values IAEA [International Atomic Energy Agency, 1994. Handbook of Parameter Values for the Prediction of Radionuclide Transfer in Temperate Environments, IAEA technical reports series No. 364. International Atomic Energy Agency, Vienna].

The effect of 5-aminoimidazole-4-carboxamide-ribonucleoside (AICAR) activation of the AMP-activated protein kinase (AMPK) on the transport of the model radiolabeled dipeptide [3H]-D-Phe-L-Gln was investigated in the human epithelial colon cancer cell line Caco-2. Uptake and transepithelial fluxes of [3H]-D-Phe-L-Gln were carried out in differentiated Caco-2 cell monolayers, and hPepT1 and glucose transporter 2 (GLUT2) protein levels were quantified by immunogold electron microscopy. AICAR treatment of Caco-2 cells significantly inhibited apical [3H]-D-Phe-L-Gln uptake, matched by a decrease in brush-border membrane hPepT1 protein but with a concomitant increase in the facilitated glucose transporter GLUT2. A restructuring of the apical brush-border membrane was seen by electron microscopy. The hPepT1-mediated transepithelial (A-to-B) peptide flux across the Caco-2 monolayers showed no significant alteration in AICAR-treated cells. The electrical resistance in the AICAR-treated monol...

Ubiquinone-10 (CoQ10), a vitamin-like lipophilic component of the membrane-bound electron transport system, has a wide range of therapeutic, neutraceutical, and cosmeceutical applications. The objective of this study was to optimize nutritional requirements for production of CoQ10 by Paracoccus dinitrificans NRRL B-3785 fermentation. Effect of type and concentration of carbon and nitrogen source on fermentation kinetic parameters were analyzed using logistic and Luedeking-Piret equations. In submerged batch fermentation, yield of CoQ10 was 12.22 mg/L when 40 g/L glycerol was used and specific growth rate (0.056/h) as well as growth associated constant (α=0.680 mg/g) were higher as compared to other concentrations. Ammonium nitrate and proteose peptone at 5 (α=0.677 mg/g; β= 0.0072 mg/g·h) and 20 g/L (α=0.806 mg/g; β=0.0074 mg/g·h), respectively, were optimal for CoQ10 production. CoQ10 formation observed to be both growth and nongrowth associated. In optimized medium CoQ10 formation increased considerably from 1.91 to 14.12 mg/L.

The active ingredient of marijuana is(−)-Δ 9 -tetrahydrocannabinol(Δ 9 -THC).Δ 9 -THC and other natural and synthetic cannabinoids such as CP-55, 940 inhibit spontaneous activity and produce catalepsy in animals in a receptor-mediated fashion. Tolerance develops to the motor ...

With declining petroleum reserves, increased world demand, and unstable politics in some of the worlds richest oil producing regions, the capability for the U.S. to produce synthetic liquid fuels from domestic resources is critical to national security and economic stability. Coal, biomass and other carbonaceous materials can be converted to liquid fuels using several conversion processes. The leading candidate for

The pharmacodynamics and pharmacokinetics of bupivacaine in solution and in liposome preparations following subcutaneous administration were studied in rats. Multilamellar vesicles entrapping bupivacaine solution were prepared. The local anaesthetic effect was estimated by the tail-flick test in Wistar rats treated with 1 mg bupivacaine in 0.2-ml. preparations. Plasma concentrations of bupivacaine were determined by high-performance liquid chromatography. The results showed that both bupivacaine solution and bupivacaine liposomes revealed local anaesthetic effects in the initial tail-flick test (15 min after injection). With bupivacaine liposomes, the duration of action was 5-fold (447 ± 28.9 vs 87 ± 6.7 min), the maximum possible effect was 2-fold (100 ± 0 vs 47.6 ± 13%), and the peak plasma concentration (Cmax) was less than one-fifth (0.12 ± 0.04 vs 0.65 ± 0.04 μg mL−1) that with bupivacaine solution. The sensory block effect of bupivacaine solution completely resolved at 90 min,...