Delta opioid peptide [D-Ala2,D-leu5]enkephalin blocks the long-term loss of dopamine transporters induced by multiple administrations of methamphetamine: involvement of opioid receptors and reactive oxygen species

Delta opioid peptide [D-Ala2,D-leu5]enkephalin (DADLE) can prolong organ preservation and increases myocardial tolerance to ischemia. Our study examined the protective property of DADLE against methamphetamine- (METH) induced dopaminergic terminal damage in the central nervous system. Because the neurotoxicity of METH involves reactive oxygen species, we also examined if DADLE might be an antioxidative agent in vitro. DADLE at 2 and 4 mg/kg (i.p.), given 30 min before each METH administration (5 or 10 mg/kg, i.p., four injections in a day at 2-hr intervals), dose-dependently blocked the METH-induced long-term dopamine transporter loss. The opioid antagonist naltrexone blocked this action of DADLE in both aspects of striata but tends not to affect the effects of DADLE in the nucleus accumbens. DADLE did not alter changes in body temperature induced by METH. The reduction of striatal dopaminergic content and tyrosine hydroxylase activity caused by METH, however, were not blocked by DADLE. In vitro, DADLE was approximately equipotent to glutathione in inhibiting both superoxide anion formation induced by xanthine oxidase and hydroxyl radical formation evoked by ferrous/citrate complex. DADLE was only slightly less potent than glutathione in inhibiting the iron/ascorbate-induced brain lipid peroxidation. These results suggest that DADLE can protect the terminal membranes of dopaminergic neurons against METH-induced insult but not the loss of dopaminergic content and tyrosine hydroxylase activity and that this action of DADLE might involve opioid receptors as well as the sequestration of free radical.     

Gelsolin is a downstream effector of rac for fibroblast motility

Rac, a member of the rho family of GTPases, when activated transmits signals leading to actin-based membrane ruffling in fibroblasts. Compared with wild-type fibroblasts, gelsolin null (Gsn-) dermal fibroblasts have a markedly reduced ruffling response to serum or EGF stimulation, which signal through rac. Bradykinin-induced filopodial formation, attributable to activation of cdc42, is similar in both cell types. Wild-type fibroblasts exhibit typical lamellipodial extension during translational locomotion, whereas Gsn- cells move 50% slower using structures resembling filopodia. Multiple Gsn- tissues as well as Gsn- fibroblasts overexpress rac, but not cdc42 or rho, 5-fold. Re-expression of gelsolin in Gsn- fibroblasts by stable transfection or adenovirus reverts the ruffling response, translational motility and rac expression to normal. Rac migrates to the cell membrane following EGF stimulation in both cell types. Gelsolin is an essential effector of rac-mediated actin dynamics, acting downstream of rac recruitment to the membrane.     

Reflections on simultaneous radio-polychemotherapy in head-neck carcinomas]

In the tissues of the herpes-infected eye of a rabbit the content of adenosine triphosphoric acid (ATP), glucose and pyroracemic acid decreases and the level of lactic acid rises, i.e. anaerobic glycolysis prevails over the aerobic decomposition of glucose. A sharp decrease in the amount of ATP in the cornea and the iris in herpetic keratitis is due to the increased consumption of ATP for the synthesis of DNA and polypeptides of herpes simplex virus, as well as to disturbances in the oxidation transformations of glucose linked with the increased proportion of anaerobic glycolysis.     

Using previous models to bias structural learning in the hierarchical BOA

Estimation of distribution algorithms (EDAs) are stochastic optimization techniques that explore the space of potential solutions by building and sampling explicit probabilistic models of promising candidate solutions. While the primary goal of applying EDAs is to discover the global optimum or at least its accurate approximation, besides this, any EDA provides us with a sequence of probabilistic models, which in most cases hold a great deal of information about the problem. Although using problem-specific knowledge has been shown to significantly improve performance of EDAs and other evolutionary algorithms, this readily available source of problem-specific information has been practically ignored by the EDA community. This paper takes the first step toward the use of probabilistic models obtained by EDAs to speed up the solution of similar problems in the future. More specifically, we propose two approaches to biasing model building in the hierarchical Bayesian optimization algorithm (hBOA) based on knowledge automatically learned from previous hBOA runs on similar problems. We show that the proposed methods lead to substantial speedups and argue that the methods should work well in other applications that require solving a large number of problems with similar structure.     

Diels-alder adducts from safflower oil fatty acids: I. Maleic anhydride as dienophile

The Diels-Alder reaction between alkali conjugated and elaidinized safflower oil fatty acids and maleic anhydride was studied under various experimental conditions. The principal product which was obtained in 51–55% yields was a mixture of the adduct of maleic anhydride and maleic acid in 40∶60 proportions. The isolation and properties of this mixed adducts from the reaction mixture and their conversion to trimethyl, tributyl and triallyl esters are described. The trimethyl ester was also obtained in good yield from the methyl esters of the fatty acids and dimethyl maleate.     

Quantitative determination of castor oil in edible and heat-abused oils by13C nuclear magnetic resonance spectroscopy

Application of¹³C nuclear magnetic resonance (NMR) spectroscopy for detection of castor oil (CO) in various edible oils, such as coconut oil, palm oil, groundnut oil and mustard oil, is described. Characteristic signals observed at δ 132.4, δ 125.6, δ 71.3, δ 36.8 and δ 35.4 ppm, due to C10, C9, C12, C13 and C11 carbons of ricinoleic acid (RA) in CO, were selected for distinguishing it from edible oils. Quantitative¹³C NMR spectra of oils were recorded in CDCl₃ with a gated decoupling technique. The minimum detection limits for qualitative and quantitative analyses were 2.0 and 3.0%, respectively. The proposed method is simple, nondestructive and requires no sample pretreatment. Its application to heat-abused oils has also been demonstrated successfully without any of the interferences observed in most other methods.     

Preparation and surface- active properties of polyoxyethylene-glycol (600) monoesters of fatty acids

Polyoxyethyleneglycol (PEG-600) monoesters of undecylenic, lauric, myristic, palmitic, stearic, oleic, ricinoleic and 12-hydroxystearic acids were prepared in 80-85% yield by reacting PEG with boric acid, esterifying the resultant borate with fatty acid, and selectively hydrolyzing the borate ester; their surface active properties were evaluated. Increase in acyl chain length increased the surface tension. The presence of a double bond or hydroxyl group in C₁₈ series improved the wetting and emulsifying proper-ties. Unsaturation in the fatty acid chain reduced the foaming power.     

Diels-alder adducts from safflower fatty acids: III. Acrylic and related acid dienophiles

The Diels-Alder adducts from alkali conjugated and elaidinized safflower fatty acids with acrylic, methacrylic, crotonic and cinnamic acids and their esters as dienophiles were obtained in 40–64% yields. Low yields of 16–18% were obtained when 10-undecenoic acid and its ester were used. Most of the adducts could be estimated quantitatively in the reaction products by column chromatography or gas liquid chromatography (GLC). For the estimation of the adducts from crotonic and 10-undecenoic acids a combination of column chromatography and GLC techniques was employed. Partitioning between hexane and 90% methanol, partial esterification with alkali washing, and splitting and fractional distillation under reduced pressure were methods used to obtain the adducts in 90–95% purity.