The role of the cytoskeletal protein, tubulin, in the mode of action and mechanism of drug resistance to benzimidazoles.

The thiol pool in human plasma: the central contribution of albumin to redox processes.

Copper is an essential component of life because of its convenient redox potential of 200-800 mV when bound to protein. Extensive insight into copper homeostasis has only emerged in the last decade and Enterococcus hirae has served as a paradigm for many aspects of the process. The cop operon of E. hirae regulates copper uptake, availability, and export. It consists of four genes that encode a repressor, CopY, a copper chaperone, CopZ, and two CPx-type copper ATPases, CopA and CopB. Most of these components have been conserved across the three evolutionary kingdoms. The four Cop proteins have been studied in vivo as well as in vitro and their function is understood in some detail.

Copper homeostasis in Enterococcus hirae

Antioxidant activity of sesame coat

Simplified 2,4-dinitrophenylhydrazine spectrophotometric assay for quantification of carbonyls in oxidized proteins

Hydrogen peroxide-mediated degradation of protein: different oxidation modes of copper- and iron-dependent hydroxyl radicals on the degradation of albumin

We investigated the structural requirements for the induction of hepatic microsomal cytochrome P450 2B1/2 (P450 2B1/2) and cytochrome P450 1A1/2 (P450 1A1/2) by imidazole- and pyridine-containing compounds in rats. Clotrimazole, an azole antifungal drug, and 1-diphenylmethylimidazole preferentially induced P450 2B1/2 in a dose-dependent manner, and slightly induced P450 1A1/2. 1-Benzylimidazole preferentially induced P450 1A1/2. 1-Phenylimidazole, which lacks the methylene bridge of 1-benzylimidazole, only induced P450 1A1/2. In turn, loss of aromaticity of the N-substituted moiety of imidazole, as in 1-cyclohexylmethylimidazole and 1-tert-butylimidazole, resulted in a preferential induction of P450 2B1/2. Likewise, various pyridine-containing compounds showed structure-dependent induction of P450 species. Namely, 4-diphenylmethylpyridine induced P450 2B1/2. 4-Benzylpyridine induced both P450 2B1/2 and P450 1A1/2. 4-Cyclohexylmethylpyridine and 4-tert-butylpyridine predominantly induced P450 2B1/2. 4-Phenylpyridine preferentially induced P450 1A1/2 rather than P450 2B1/2. Oxygenation products at the methylene bridge, 4-benzoylpyridine and phenyl-4-pyridylmethanol, could not induce P450 1A1/2. In turn, 2,4'-dipyridyl induced both P450 2B1/2 and P450 1A1/2, but not 2,2'-dipyridyl. 4,4'-Trimethylenedipyridine preferentially induced P450 1A1/2 at very low doses. These findings indicate that imidazole- and pyridine-containing compounds having lipophilic groups are inducers of hepatic P450, and that such compounds having aromatic groups and taking coplanar conformational structures are potent inducers of P450 1A1/2.

Structural requirements for the induction of hepatic microsomal cytochrome P450 by imidazole- and pyridine-containing compounds in rats.

Ebelactones A and B, natural products from Streptomyces aburaviensis are potent inhibitors of pancreatic lipase. Lipase is the key enzyme required for the absorption of dietary triglycerides (TG). Ebelactone B inhibited, in a dose-dependent manner, the intestinal absorption of fat after fat-feeding in the rat. The most effective inhibition was observed when the inhibitor was administered at 60 min prior to fat-feeding. When ebelactone B (10 mg/kg) was administered, the serum levels of TG (58%) and cholesterol (36%) were decreased. Since ebelactone B effectively inhibits absorption of dietary fat, it may provide a promising means for prophylaxis or therapeutics of hyperlipidemia and obesity.

Effects of Ebelactone B, a Lipase Inhibitor, on Intestinal Fat Absorption in the Rat

PURPOSE:To suppress engine stall in deceleration by increasing the idle air amount by a prescribed amount if a throttle valve is completely closed when the idle revolution number is feedback-controlled by controlling the flow-rate of the intake air which detours around the throttle valve. CONSTITUTION:An idle revolution-speed controlling valve 26 is installed in a by-pass 24 which is installed so as to detour a throttle valve 18 in an intake passage, and is controlled, in idle operation, by a digital control circuit 54 according to the difference between the engine revolution number which is obtained from the output of a crank angle sensor 44 and the aimed idle revolution number. If the reduction speed of the engine revolution number becomes over a prescribed value and the idle air correction amount which is obtained according to said reduction speed becomes larger than the preceding value, when the throttle valve 18 is completely closed, the control circuit 54 corrects to increase the amount of idle air. After the above increase is corrected, the engine is controlled slowly in a prescribed deceleration speed.

Control of idle revolution number of internal- combustion engine

PURPOSE:To prevent drop of an engine rotational speed and stall at transition, by increasing an amount of air bypassing a throttle valve over a target amount of air under load upon receiving a load and decreasing the amount of air to the target amount at a fixed rate. CONSTITUTION:A target rotational speed NF according to an operational condition and an estimated duty ratio De according to an estimated amount of air are set. When an ISC timing is reached, an average value NE of an engine rotational speed is calculated, and a basic duty ratio Do for feedback controlling the average value NE to the target rotational speed NF is calculated. When a load is received, the estimated duty ratio De for feedforward control is added to the basic duty ratio Do to determine a control duty ratio D. If a feedback control condition is established, an opening degree of an ISC valve is controlled by the control duty ratio D so that the average value of the engine rotational speed may become the target rotational speed.

Fukuda Teruo

Papers

Hydrogen peroxide-mediated degradation of protein: different oxidation modes of copper- and iron-dependent hydroxyl radicals on the degradation of albumin

Structural requirements for the induction of hepatic microsomal cytochrome P450 by imidazole- and pyridine-containing compounds in rats.

Effects of Ebelactone B, a Lipase Inhibitor, on Intestinal Fat Absorption in the Rat

Control of idle revolution number of internal- combustion engine

Method of controlling rotational speed of internal-combustion engine