Casualties caused by nerve agents, potent acetylcholinesterase inhibitors, have attracted attention from media recently. Poisoning with these chemicals may be fatal if not correctly addressed. ...Therefore, research on novel antidotes is clearly warranted. Pyridinium oximes are the only clinically available compounds, but poor penetration into the blood-brain barrier hampers efficient enzyme reactivation at the central nervous system. In searching for structural factors that may be explored in SAR studies, we synthesized and evaluated neutral aryloximes as reactivators for acetylcholinesterase inhibited by NEMP, a VX surrogate. Although few tested compounds reached comparable reactivation results with clinical standards, they may be considered as leads for further optimization.
•A practical method for synthesis of neutral aryloximes is presented.•A VX surrogate was used as inhibitor for Electrophorus eel Acetylcholinesterase.•Neutral aryloximes retrieved promising predicted properties for use as reactivators.•Seven compounds were identified as potential leads for further optimization.
Chiral myo‐inositol derivatives play key roles in cell‐signaling processes. Despite the relevance of these compounds, few syntheses of them rely on enantioselective catalytic reactions. Even fewer ...reports describe the use of desymmetrization of myo‐inositol derivatives. In fact, most routes involve resolution by derivatization. Thus, a symmetrical partially protected myo‐inositol derivative, 1,3‐di‐O‐benzyl‐myo‐inositol (1), was used as a substrate in fast lipase‐catalyzed desymmetrization reactions. Among the lipases tested, both Lipozyme RM‐IM and Lipozyme TL‐IM were effective in catalyzing the formation of the chiral acetate l‐(+)‐6‐O‐acetyl‐1,3‐di‐O‐benzyl‐myo‐inositol l‐(+)‐2 with high conversion (98–99 %) and ee (>99 %). Conversely, Novozyme 435 and Lipomod 34P as biocatalysts showed different regioselectivity, leading to the formation of the symmetrical 5‐O‐acetylated product. We were able to reuse TL‐IM lipase seven times without any noticeable decrease in the conversion. Acetate l‐(+)‐2 is a potential precursor of biologically active myo‐inositol derivatives and other relevant materials for cell biology studies.
Depending on the choice of lipase, 1,3‐di‐O‐benzyl‐myo‐inositol (1) either undergoes desymmetrization to form l‐(+)‐6‐O‐acetyl‐1,3‐di‐O‐benzyl‐myo‐inositol (with Lipozyme RM‐IM or Lipozyme TL‐IM), or is transformed into the meso 5‐O‐acetyl derivative 3 (with Novozym 435).
ABSTRACT We present an unprecedented measurement of the disk stability and local instability scales in the luminous infrared Seyfert 1 host, NGC 7469, based on ALMA observations of dense gas tracers ...and with a synthesized beam of 165 × 132 pc. While we confirm that non-circular motions are not significant in redistributing the dense interstellar gas in this galaxy, we find compelling evidence that the dense gas is a suitable tracer for studying the origin of its intensely high-mass star-forming ringlike structure. Our derived disk stability parameter accounts for a thick disk structure, and its value falls below unity at the radii in which intense star formation is found. Furthermore, we derive the characteristic instability scale and find a striking agreement between our measured scale of ∼180 pc and the typical sizes of individual complexes of young and massive star clusters seen in high-resolution images.
The effects of particle discreteness in N-body Lambda CDM simulations are still an intensively debated issue. In this paper we explore such effects, taking into account the scatter caused by the ...randomness of the initial conditions and focusing on the statistical properties of the cosmological density field. For this purpose, we run large sets of Lambda CDM simulations and analyze them using a wide variety of diagnostics, including new and powerful wavelet statistics. Among other facts, we point out (1) that dynamical evolution does not propagate discreteness noise up from the small scales at which it is introduced and (2) that one should aim to satisfy the condition epsilon image 2d, where epsilon is the force resolution and d is the interparticle distance. We clarify what such a condition means and how to implement it in modern cosmological codes.
This review describes compounds produced microalgae, such as biodiesel, lipids, fatty acids (FA), triacylglycerides (TAG), and pigments (phycobilins, chlorophylls, and carotenoids). We discuss the ...factors inducing the accumulation of these metabolites and their economic importance. We focused on cell wall breaking methods of microalgae used to produce biodiesel. A special approach was made to extremophile microalgae used in biodiesel production. The type of methodology used in the cultivation and the use of extremophiles microalgae can permit feasible biodiesel production.
Two experiments (E) were carried out to evaluate the effects of fumaric acid and an acidifier blend composed by calcium formate, calcium lactate and medium-chain fatty acids (capric and caprylic) in ...piglet diets containing colistin (40 ppm) or halquinol (120 ppm) on performance, diarrhea incidence (E1), organs relative weight, pH values, intestinal morphometry and microbiota (E2). In E1, 192 and E2, 24 piglets weaned at 21-day-old were randomly assigned to blocks with 2x2 factorial arrangement of treatments absence or presence of fumaric acid x absence or presence of acidifier blend, six replicates of eight (E1) and one piglet per pen (E2). For E1, the treatments were control (CD): no acidifier product + 40 ppm of colistin, FA: fumaric acid in absence of acidifier blend, AB: acidifier blend in absence of fumaric acid and, AF+AB: presence of fumaric acid and acidifier blend. For E2, the pre-starter I diet were used and the same treatments as E1 evaluated. No treatment effects (P>0.05) were observed on performance, diarrhea incidence (E1), gut pH values and duodenum morphometry of piglets (E2). However, the addition of AB increased (P<0.05) large intestine relative weight and, FA addition decreased (P<0.05) pancreas relative weight, jejunum villi height and, total coliform and E. coli counts in cecum. The inclusion of FA and AB in diets containing colistin or halquinol did not improve performance, although FA exerted an inhibitory effect on cecum microbiota.
Isotope-ratio mass spectrometry (IRMS) is a potential tool that provides time-integrated estimate of assimilated and not just ingested nutrients. This feature turned possible its application to ...evaluate the effects of dietary nucleotides and glutamate on carbon turnover (δ13C) in the brain of weanling piglets. Eighty-seven piglets weaned at 21-day-old were used, being three piglets slaughtered at day-0 (prior to diet-switch) and, the remaining 84 randomly assigned in a complete block design with a 2 x 2 factorial arrangement of treatments (two nucleotide levels: 0% and 0.1% and, two glutamate levels: 0% and 1%). On trial days 3, 6, 9, 14, 21, 35 and 49, three piglets per treatment were also slaughtered. The samples were analyzed by IRMS and adjusted to the first-order equation by a nonlinear regression analysis using NLIN procedure of SAS, in order to obtain the exponential graphics. The carbon turnover (t95%) verified for cerebral tissue was faster (P<0.05) for diet containing glutamate in comparison to other diets, supporting the fact that glutamate contributed to develop the piglets' brain, due to the fastest incorporation of 13C-atoms in this tissue at post-weaning phase, despite the energy deficit experienced by them.
We present a new measurement of $J/\psi$ production in Pb-Pb collisions at 158 GeV/nucleon, from the data sample collected in year 2000 by the NA50 Collaboration, under improved experimental ...conditions with respect to previous years. With the target system placed in vacuum, the setup was better adapted to study, in particular, the most peripheral nuclear collisions with unprecedented accuracy. The analysis of this data sample shows that the ($J/\psi$)/Drell-Yan cross-sections ratio measured in the most peripheral Pb-Pb interactions is in good agreement with the nuclear absorption pattern extrapolated from the studies of proton-nucleus collisions. Furthermore, this new measurement confirms our previous observation that the ($J/\psi$)/Drell-Yan cross-sections ratio departs from the normal nuclear absorption pattern for semi-central Pb-Pb collisions and that this ratio persistently decreases up to the most central collisions.
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