Monitoring of the Physical and Chemical Properties of a Gasoline Engine Oil during Its Usage

Physicochemical properties of a mineral-based gasoline engine oil have been monitored at 0, 500, 1000, 2000, 3500, 6000, 8500, and 11500 kilometer of operation. Tracing has been performed by inductively coupled plasma and some other techniques. At each series of measurements, the concentrations of twenty four elements as well as physical properties such as: viscosity at 40 and 100°C; viscosity index; flash point; pour point; specific gravity; color; total acid and base numbers; water content have been determined. The results are indicative of the decreasing trend in concentration of additive elements and increasing in concentration for wear elements. Different trends have been observed for various physical properties. The possible reasons for variations in physical and chemical properties have been discussed

Diversity oriented synthesis of fused heterocycles from the cascade reactions of indigo with allylic and propargylic systems

Diversity-oriented synthesis based on the cascade allylation chemistry of indigo, with its 2,2\u27-bisindolic system, has resulted in rapid access to new examples of the hydroxy- 8a,13-dihydroazepino[1,2-a:3,4-b\u27]diindol-14(8H)-one (248-250) skeleton in up to 51% yield. Additionally the presence of the terminal substituent on the allylic substrates provided selectivity in production of 1-allyl-5\u27-allyloxy-3\u27,4\u27-dihydrospiroindoline- pyrido[1,2-a]indol-ones systems (227-231) in up to 69%, where as the absence of the substituent on the terminal position of the allylic systems resulted in production of pyridoindolo-azepino[1,2-a]indol-11(7H)-ones heterocycles (232-236) in up to 72% yield. Quantitative generation of N-substituted indigo provided the mechanistic insights and preliminary measures to control the outcome of the cascade reactions. The base- induced propargylation of indigo resulted in the rapid one-pot synthesis of three different classes of heterocycles. The pyrazinodiindole 264 in 14%, pyridodiindole 265 in 17% yield and benzoindolonaphthyridinone 266 in 31% yield. The compounds 265 and 266 are possess the same framework of fascaplycin and ring B homologue, respectively. Further optimisation via alteration of the leaving group of the propargylic system from bromine to mesylate resulted in synthesis of the 265 and 266 with higher yields, 28% and 52% respectively. The presence of a phenyl substituent on the terminal alkynic position of the propargyl unit resulted in formation of oxadiazocinodiindole 271 in 62%. Initial biological activity studies with these new heterocyclic derivatives indicated promising in vitro antiplasmodial activity as well as good anticancer activity. The chemistry described is new for the indigo moiety and cascade reactions from this readily available and cheap starting material should be more broadly applicable in the synthesis of additional new heterocyclic systems, difficult to access by other means

Rapid cascade synthesis of poly-heterocyclic architectures from indigo

The base-induced propargylation of the dye indigo results in the rapid and unprecedented one-pot synthesis of highly functionalized representatives of the pyrazino[1,2-a:4,3-a′]diindole, pyrido[1,2-a:3,4-b′]diindole and benzo[b]indolo[1,2-h]naphthyridine heterocyclic systems, with the last two reflecting the core skeleton of the anticancer/antiplasmodial marine natural products fascaplysin and homofascaplysins and a ring B-homologue, respectively. The polycyclic compounds 6–8, whose structures were confirmed through single-crystal X-ray crystallographic analysis, arise from sequential inter/intramolecular substitution–addition reactions, and in some cases, ring rearrangement reactions. Preliminary studies on controlling the reaction path selectivity, and the potential reaction mechanisms, are also described. Initial biological activity studies with these new heterocyclic derivatives indicated promising in vitro antiplasmodial activity as well as good anticancer activity. The chemistry described is new for the indigo moiety and cascade reactions from this readily available and cheap starting material should be more broadly applicable in the synthesis of additional new heterocyclic systems difficult to access by other means

Latin American Indian literatures journal : a review of American Indian texts and studies

Diversity-directed synthesis based on the cascade allylation chemistry of indigo, with its embedded 2,2’-diindolic core, has resulted in rapid access to new examples of the hydroxy-8a,13-dihydroazepino[1,2-a:3,4-b']diindol-14(8H)-one skeleton in up to 51% yield. Additionally a derivative of the novel bridged heterocycle 7,8-dihydro-6H-6,8a-epoxyazepino[1,2-a:3,4-b']diindol-14(13H)-one was produced when the olefin of the allylic substrate was terminally disubstituted. Further optimisation also produced viable one-pot syntheses of derivatives of the spiro(indoline-2,9'-pyrido[1,2-a]indol)-3-one (65%) and pyrido[1,2,3-s,t]indolo[1,2-a]azepino[3,4-b]indol-17-one (72%) heterocyclic systems. Ring-closing metathesis of the N,O-diallylic spiro structure and subsequent Claisen rearrangement gave rise to the new (1R,8aS,17aS)-rel-1,2-dihydro-1-vinyl-8H,17H,9H-benz[2',3']pyrrolizino[1',7a':2,3]pyrido[1,2-a]indole-8,17-(2H,9H)-dione heterocyclic system

Rapid Cascade Synthesis of Poly-Heterocyclic Architectures from Indigo

The base-induced propargylation of the dye indigo results in the rapid and unprecedented one-pot synthesis of highly functionalized representatives of the pyrazino­[1,2-<i>a</i>:4,3-<i>a</i>′]­diindole, pyrido­[1,2-<i>a</i>:3,4-<i>b</i>′]­diindole and benzo­[<i>b</i>]­indolo­[1,2-<i>h</i>]­naphthyridine heterocyclic systems, with the last two reflecting the core skeleton of the anticancer/antiplasmodial marine natural products fascaplysin and homofascaplysins and a ring B-homologue, respectively. The polycyclic compounds <b>6</b>–<b>8</b>, whose structures were confirmed through single-crystal X-ray crystallographic analysis, arise from sequential inter/intramolecular substitution–addition reactions, and in some cases, ring rearrangement reactions. Preliminary studies on controlling the reaction path selectivity, and the potential reaction mechanisms, are also described. Initial biological activity studies with these new heterocyclic derivatives indicated promising in vitro antiplasmodial activity as well as good anticancer activity. The chemistry described is new for the indigo moiety and cascade reactions from this readily available and cheap starting material should be more broadly applicable in the synthesis of additional new heterocyclic systems difficult to access by other means

Regular Exercise or Food Restriction, Which is Better in the Event of Heart Failure? An Approach to Oxidative Stress and Angiogenesis

The aim of present study was to investigate whether food restriction combined with exercise training could attenuate the oxidative stress and promote angiogenesis in a rat model of heart failure. 50 male wistar rats weighing 250-300 g were randomly divided into 5 groups including: 1) sham; they were fed ad libitum food, n=10. 2) Heart failure group; 3) Exercise group; they run on a treadmill 5 days per week for 4 weeks, n=10. 4) Food restricted group; they were fed with 60% of their daily average food intake, n=10. 5) Food restricted plus exercise group; as well as feeding with 60% of their daily average food intake for 8 weeks and run on a treadmill 5 days for the 4 next weeks, n=10. Subcutaneous injection of isoproterenol (130 mg/kg) was used to induce experimental heart failure. Echocardiographic parameters were monitored. Plasma levels of malondialdehyde (MDA) and prooxidant/ antioxidant balance (PAB), as oxidative parameters were measured. In continue gene expression of angiogenic factors such as hypoxia inducible factor-1a (HIF-1a), vascular endothelial growth factor A (VEGFA) and endothelial nitric oxide synthase (eNOS) as well as histopathological examination were investigated. Isoproterenol-treated hearts showed lower functional indexes including LVEDd; Left Ventricular End Diastolic dimension (p<0.05), FS; Fractional Shortening (p<0.001), EF; Ejection Fraction, (p<0.001). In addition, significant increase in plasma levels of MDA (p<0.001) and PAB (p<0.001) were observed. Food restriction and exercise significantly improved all measured parameters. The protective role of food restriction and exercise training on myocardial damage was further confirmed by promoting the gene expression of angiogenic factors (p<0.001) in left ventricle and reducing the myocardial fibrosis (p<0.05). Our results suggest that combined food restriction with exercise training is superior to either therapy alone for improving functional indexes, strengthen balance of antioxidative defense system, as well as gene expression of angiogenic factors and decreasing myocardial fibrosis

Acute sleep deprivation preconditions the heart against ischemia/ reperfusion injury: the role of central GABA-A receptors

Objective(s): Central γ-aminobutyric acid (GABA) neurotransmission modulates cardiovascular functions and sleep. Acute sleep deprivation (ASD) affects functions of various body organs via different mechanisms. Here, we evaluated the effect of ASD on cardiac ischemia/reperfusion injury (IRI), and studied the role of GABA-A receptor inhibition in central nucleus of amygdala (CeA) by assessing nitric oxide (NO) and oxidative stress. Materials and Methods: The CeA in sixty male Wistar rats was cannulated for saline or bicuculline (GABA-A receptor antagonist) administration. All animals underwent 30 min of coronary occlusion (ischemia), followed by 2 hr reperfusion (IR). The five experimental groups (n=12) included are as follows: IR: received saline; BIC+IR: received Bicuculline; MLP+IR: received saline, followed by the placement of animals in an aquarium with multiple large platforms; ASD+IR: underwent ASD in an aquarium with multiple small platforms; and BIC+ASD+IR: received bicuculline prior to ASD. Results: Bicuculline administration increased the malondialdehyde levels and infarct size, and decreased the NO metabolites levels and endothelial nitric oxide synthase (eNOS) gene expression in infarcted and non-infarcted areas in comparison to IR group. ASD reduced malondialdehyde levels and infarct size and increased NO metabolites, corticosterone levels and eNOS expression in infarcted and non-infarcted areas as compared to the IR group. Levels of malondialdehyde were increased while levels of NO metabolites, corticosterone and eNOS expression in infarcted and non-infarcted areas were reduced in the BIC+ASD+IR as compared to the ASD+IR group. Conclusion: Blockade of GABA-A receptors in the CeA abolishes ASD-induced cardioprotection by suppressing oxidative stress and NO production

Rapid Cascade Synthesis of Poly-Heterocyclic Architectures from Indigo

The base-induced propargylation of the dye indigo results in the rapid and unprecedented one-pot synthesis of highly functionalized representatives of the pyrazino­[1,2-<i>a</i>:4,3-<i>a</i>′]­diindole, pyrido­[1,2-<i>a</i>:3,4-<i>b</i>′]­diindole and benzo­[<i>b</i>]­indolo­[1,2-<i>h</i>]­naphthyridine heterocyclic systems, with the last two reflecting the core skeleton of the anticancer/antiplasmodial marine natural products fascaplysin and homofascaplysins and a ring B-homologue, respectively. The polycyclic compounds <b>6</b>–<b>8</b>, whose structures were confirmed through single-crystal X-ray crystallographic analysis, arise from sequential inter/intramolecular substitution–addition reactions, and in some cases, ring rearrangement reactions. Preliminary studies on controlling the reaction path selectivity, and the potential reaction mechanisms, are also described. Initial biological activity studies with these new heterocyclic derivatives indicated promising in vitro antiplasmodial activity as well as good anticancer activity. The chemistry described is new for the indigo moiety and cascade reactions from this readily available and cheap starting material should be more broadly applicable in the synthesis of additional new heterocyclic systems difficult to access by other means