Objective
Narcolepsy is caused by loss of the hypothalamic neurons producing the orexin/hypocretin neuropeptides. One key target of the orexin system is the histaminergic neurons of the ...tuberomammillary nucleus (TMN), an essential wake‐promoting system. As cerebrospinal fluid histamine levels may be low in patients with narcolepsy, we examined histaminergic neurons in patients with narcolepsy and in 2 mouse models of narcolepsy.
Methods
We counted the number of hypothalamic neurons producing orexin, melanin‐concentrating hormone, and histamine in 7 narcolepsy patients and 12 control subjects using stereological techniques. We identified histaminergic neurons using immunostaining for histidine decarboxylase. We also examined these systems in 6 wild‐type mice, 6 orexin/ataxin‐3 transgenic mice, and 5 orexin ligand knockout mice.
Results
Compared to controls, narcolepsy patients had 94% more histaminergic TMN neurons (233,572 ± 49,476 vs 120,455 ± 10,665, p < 0.001). This increase was higher in 5 narcolepsy patients with >90% orexin neuron loss than in 2 patients with ≤75% orexin neuron loss (252,279 ± 46,264 vs 186,804 ± 1,256, p = 0.03). Similarly, the number of histaminergic TMN neurons was increased 53% in orexin ligand knockout mice compared to wild‐type mice, whereas orexin/ataxin‐3 transgenic mice showed an intermediate 28% increase.
Interpretation
This surprising increase in histaminergic neurons in narcolepsy may be a compensatory response to loss of excitatory drive from the orexin neurons and may contribute to some of the symptoms of narcolepsy such as preserved consciousness during cataplexy and fragmented nighttime sleep. In addition, this finding may have therapeutic implications, as medications that enhance histamine signaling are now under development. Ann Neurol 2013;74:794–804
Technologies of membrane-based gas separation can be integrated into existing industrial processes for low-temperature helium recovery from natural gas at the stages of crude helium separation from ...the N
2
/He mixture and its purification. The effectiveness of these processes is most affected by the properties of the materials from which the membrane is made. Due to their unique properties, metal-organic framework are promising materials for use in gas separation. In the present work, both the Monte Carlo and equilibrium molecular dynamics methods were employed to examine the temperature dependence of membrane selectivity and nitrogen permeability for separation of an equimolar mixture of N
2
and He by a HKUST-1-based membrane at a pressure drop of 0.1, 0.3, and 1 MPa. It was shown that the selection of optimal temperature conditions made it possible to obtain a significant increase in membrane selectivity and permeability for nitrogen compared to corresponding parameters at room temperature.
A new representative of novel chiral
P*, N
-bidentate bicyclic phosphoramidite ligands was synthesized. Palladium catalysts based on this ligand were tested in the asymmetric allylic alkylation of (
...E
)-1,3-diphenylallyl acetate with dimethyl malonate and in the amination of the same substrate with pyrrolidine and demonstrated high activity (up to 100% conversion) and enantioselectivity up to 40%
ee
.
The features and trends of coal mining in the east of Russia are examined. The current and planned managerial decisions connected with coal production and supplies to competitive markets are ...analyzed. The coal products are ROM fuel, concentrate and middlings. The authors discuss approaches to effective mining and processing management within the chains of supplies, and to provision of the required quality of solid fuel produced and delivered to customers.
New readily accessible aminodiol and diaminoalcohol were obtained using simple condensation and reduction reactions. On their basis, earlier unknown ligands of bicyclophosphite nature with asymmetric ...phosphorus atoms were synthesized.
A nontrivial smooth steady incompressible Euler flow in three dimensions with compact support is constructed. Another uncommon property of this solution is the dependence between the Bernoulli ...function and the pressure.
Introduction. In the process of convective drying, there is a contradiction between drying speed and energy efficiency. One of the solutions to this contradiction is the use of targeted energy supply ...to the product. The method of targeted energy supply is the use of electromagnetic radiation in the drying process.
Aim of the Article. The study was aimed at obtaining the coefficients of a logarithmic model for calculating the performance of a belt IR dryer for drying carrots.
Materials and Methods. There were studied a modular belt IR dryer with the ability to control the speed of the belt and the power of the emitters. To describe the process, there were used standard models of the dependence of relative water content on drying time.
Results. An analysis of the drying rate curves showed an extreme effect of the belt speed on the drying rate. At belt speeds above 10 mm/s, an increase in belt speed leads to an increase in the duration of the drying process. To describe the kinetics of the drying process at IR powers of 170, 300, and 450 W, there was used a logarithmic model, as it most adequately describes the experimental data.
Discussion and Conclusion. For this type of dryers it is recommended to use the belt speed of about 10 mm/sec. The obtained coefficients of the logarithmic model are used to calculate the capacity of the drying unit.
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