Conformation selective resonance emission spectra are reported for gas-phase iodocyclohexane with excitation wavelengths of 199.8 and 204.2 nm. These spectra reveal seven Franck-Condon active ...vibrational modes for the axial conformation and eleven Franck-Condon vibrations for the equatorial conformation, and indicate that the initial dynamics on the B- and C-states have a complex multidimensional character with contributions from the CCC, CCH and HCI bending motions, torsional motions, and CI, CC, and CH stretching motions for both conformations. The resonance emission spectra are generally consistent with the previously reported assignments of the far ultraviolet absorption spectra.
We report resonance Raman spectra of selected I
2:olefin complexes obtained with excitation within the ∼270 nm absorption band of the complex. Most of the Raman intensity appears in the overtones and ...combination bands of the nominal I–I stretch and CC stretch modes. Ab initio calculations were done to examine the structure of the ground state of the complex. The Raman vibrational frequencies and the ab initio optimized geometry indicate both the I–I and CC bond order decrease moderately in the ground state complex.
P-type silicon wafers (100) with resistivities of 0.1-0.9 Omega cm were electrochemically etched in 2% HF solution at 0.7077 mA cm super(-2). The photoluminescence (PL) spectra for each wafer were ...monitored in situ using a low power 325 nm (He/Cd Laser) source and detected with a charged coupled detector (CCD) system. Three bands at 540 nm, 570 nm, and 612 nm were observed in the photoluminescence spectra. The band intensities grew with time until about 15 min of etching had occurred. The growth of PL intensities generally correlates with the surface morphologies and increase in roughness found from ex situ atomic force microscopy (AFM) of similarly etched samples. Ex situ PL characterization was also performed for the AFM analyzed samples. While the time profiles of the ex situ and in situ PL intensities were about the same, the ex situ peak intensities at longer wavelengths continued to increase after 15 min. The results of energy dispersive X-ray analysis (EDX) suggested that this may be due to the effect of oxygen in the air exposed samples.
Asprosin is a recently discovered fasting-induced hormone that promotes hepatic glucose production. Here we demonstrate that asprosin in the circulation crosses the blood-brain barrier and directly ...activates orexigenic AgRP
neurons via a cAMP-dependent pathway. This signaling results in inhibition of downstream anorexigenic proopiomelanocortin (POMC)-positive neurons in a GABA-dependent manner, which then leads to appetite stimulation and a drive to accumulate adiposity and body weight. In humans, a genetic deficiency in asprosin causes a syndrome characterized by low appetite and extreme leanness; this is phenocopied by mice carrying similar mutations and can be fully rescued by asprosin. Furthermore, we found that obese humans and mice had pathologically elevated concentrations of circulating asprosin, and neutralization of asprosin in the blood with a monoclonal antibody reduced appetite and body weight in obese mice, in addition to improving their glycemic profile. Thus, in addition to performing a glucogenic function, asprosin is a centrally acting orexigenic hormone that is a potential therapeutic target in the treatment of both obesity and diabetes.
Inhibitors of coagulation factor Xa (fXa) have emerged as a new class of antithrombotics but lack effective antidotes for patients experiencing serious bleeding. We designed and expressed a modified ...form of fXa as an antidote for fXa inhibitors. This recombinant protein (r-Antidote, PRT064445) is catalytically inactive and lacks the membrane-binding γ-carboxyglutamic acid domain of native fXa but retains the ability of native fXa to bind direct fXa inhibitors as well as low molecular weight heparin-activated antithrombin III (ATIII). r-Antidote dose-dependently reversed the inhibition of fXa by direct fXa inhibitors and corrected the prolongation of ex vivo clotting times by such inhibitors. In rabbits treated with the direct fXa inhibitor rivaroxaban, r-Antidote restored hemostasis in a liver laceration model. The effect of r-Antidote was mediated by reducing plasma anti-fXa activity and the non-protein bound fraction of the fXa inhibitor in plasma. In rats, r-Antidote administration dose-dependently and completely corrected increases in blood loss resulting from ATIII-dependent anticoagulation by enoxaparin or fondaparinux. r-Antidote has the potential to be used as a universal antidote for a broad range of fXa inhibitors.
Fatty acid synthase (FASN) predominantly generates straight-chain fatty acids using acetyl-CoA as the initiating substrate. However, monomethyl branched-chain fatty acids (mmBCFAs) are also present ...in mammals but are thought to be primarily diet derived. Here we demonstrate that mmBCFAs are de novo synthesized via mitochondrial BCAA catabolism, exported to the cytosol by adipose-specific expression of carnitine acetyltransferase (CrAT), and elongated by FASN. Brown fat exhibits the highest BCAA catabolic and mmBCFA synthesis fluxes, whereas these lipids are largely absent from liver and brain. mmBCFA synthesis is also sustained in the absence of microbiota. We identify hypoxia as a potent suppressor of BCAA catabolism that decreases mmBCFA synthesis in obese adipose tissue, such that mmBCFAs are significantly decreased in obese animals. These results identify adipose tissue mmBCFA synthesis as a novel link between BCAA metabolism and lipogenesis, highlighting roles for CrAT and FASN promiscuity influencing acyl-chain diversity in the lipidome.
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