Our Communication did not emphasize important safety considerations in the reported reactions.Buchwald and co-workers previously studied the Ti-catalyzed reduction of amides to amines or enamines. 1 Additionally, in 1992, Berk and Buchwald reported the combination of 5 mol % Ti(O-i-Pr) 4 with 2.5-3.0 equiv of (EtO) 3 SiH for the reduction of esters to silyl ethers at 40-55°C. 2 An attempt to use this procedure for the reduction of a methyl ester (90 mmol) with triethoxysilane (313 mmol) resulted in the formation of an extremely pyrophoric gas (possibly SiH 4 ), leading to several fires and an explosion. 3 During our studies on the reduction of amides, we used triethoxysilane without incident, although the Material Safety Data Sheet indicates that this chemical is a corrosive and flammable liquid. Due to the previously reported hazards, we advise that methyldiethoxysilane be used instead of triethoxysilane for the large-scale (>1 g) reduction of amides. As shown in the Supporting Information of our Communication, methyldiethoxysilane and other organosilanes can also be used for the reduction of amides at slightly higher temperature, e.g. 60°C. We thank Professor Buchwald for pointing out these latent safety problems with triethoxysilane. Literature Cited(1) Kreutzer, K. A.Page 5907. The crystal structure reported was not that of (FI 2 Ni 2 PMe 3 ) · PMe 3 but that of a decomposition product. The structure is now clarified by Delferro et al. 1 Literature Cited(1) Delferro, M.; Weberski, M. P., Jr.; Rodriguez, B. A.; Marks, T. J.Acta Crystallogr. 2010, E66, m258.We regret the omission of a prior publication describing the relative affinities of poly [(9,9-bis(6′-N,N,N-trimethylammonium)hexyl)fluorene-alt-1,4-phenylene]bromide (PFP-Br) and single-and double-stranded DNA that has recently come to our attention. Some years prior to our work, Liu and Bazan 1 demonstrated improved fluorescence energy transfer from PFP, Br to acceptor-labeled single-stranded DNA relative to transfer to acceptor-labeled double-stranded DNA. We hereby acknowledge this precedent. Literature Cited (1) Liu, B.; Bazan, G. C.
This paper presents a bi-directional dc-dc converter for use in low power applications. The proposed topology is based on a half-bridge on the primary and a current fed pushpull on the secondary side of a high frequency isolation transformer. Achieving bi-directional flow of power using the same power components provides a simple, efficient and galvanically isolated topology that is specially attractive for use in battery charge/ discharge circuits in DC UPS. In the presence of the dc mains (provided by the ac mains), the converter essentially operates in the buck mode to power the load and charge the battery. On failure of the dc mains, operation is comparable to that of a boost converter and the battery supplies the load power. Small signal and steady state analyses are presented for this specific application. Design guidelines for a laboratory prototype are included. Experimental results validate and evaluate the proposed topology.
Background:The eSS rats display a mild non obese type 2 diabetic syndrome with an insulin resistant state characterized by hyperglycemia, dyslipidemia and hyperinsulinemia. During the first year, eSS male rats exhibit proteinuria as well as alterations in glomerular filtration. Methods:In this study, some hematological characteristics were evaluated in 12 month-old eSS males compared to eumetabolic Wistar rats, and the renal histology was also studied. Results:The diabetic rats were found to have fewer erythrocytes and lower values of hemoglobin. In eSS rats, peripheral blood smears showed immature erythrocytes with polychromatophilia and the presence of erythroblasts was also verified. Thickening of the glomerular basement membrane, areas of tubular dilatation and protein cylinders were observed in kidneys of diabetic animals. Conclusions:Our results suggest that eSS rats develop anemia because of complex influences of metabolic disturbances and diabetic renal damage and that it might provide new opportunities for studying the pathogenesis of this relevant complication of type 2 diabetics.
Longevity is dictated by a combination of environmental and genetic factors. One of the key mechanisms implicated in regulating lifespan extension is the ability to induce protein chaperones to promote protein homeostasis. However, it is unclear whether protein chaperones exclusively regulate longevity. Previous work has shown that activating the unfolded protein response of the endoplasmic reticulum (UPR ER ) in neurons can signal peripheral tissues to promote chaperone expression, thus enhancing organismal stress resistance and extending lifespan. Here, we find that this activation not only promotes chaperones, but facilitates a dramatic restructuring of ER morphology in intestinal cells. This restructuring, which includes depletion of lipid droplets, ER expansion, and ER tubulation, depends of lipophagy. Surprisingly, we find that lipophagy is required for lifespan extension and is completely independent of chaperone function. Therefore, UPR induction in neurons triggers two distinct programs in the periphery: the canonical arm through protein chaperones, and a non-canonical mechanism through lipid depletion. In summary, our study identifies lipophagy as an integral component of UPR ER -induced longevity. MAINLife presents a myriad of challenges, stressors, and environmental shifts to which cells must adapt in order to survive and thrive. The homeostatic regulation of protein folding (proteostasis), which is monitored in specific subcellular compartments (the endoplasmic reticulum (ER), mitochondria, cytosol) is an integral player in stress resistance and longevity. The ER, in particular, is a central regulator of stress monitoring since it controls (1) nearly a third of the cell's proteins, (2) provides an internal medium and transponder for lipid homeostasis and cell signaling, and (3) communicates directly with all other organelles to maintain cellular secretion.
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