31 research outputs found
Cholinergic Modulation of Narcoleptic Attacks in Double Orexin Receptor Knockout Mice
To investigate how cholinergic systems regulate aspects of the sleep disorder narcolepsy, we video-monitored mice lacking both orexin (hypocretin) receptors (double knockout; DKO mice) while pharmacologically altering cholinergic transmission. Spontaneous behavioral arrests in DKO mice were highly similar to those reported in orexin-deficient mice and were never observed in wild-type (WT) mice. A survival analysis revealed that arrest lifetimes were exponentially distributed indicating that random, Markovian processes determine arrest lifetime. Low doses (0.01, 0.03 mg/kg, IP), but not a high dose (0.08 mg/kg, IP) of the cholinesterase inhibitor physostigmine increased the number of arrests but did not alter arrest lifetimes. The muscarinic antagonist atropine (0.5 mg/kg, IP) decreased the number of arrests, also without altering arrest lifetimes. To determine if muscarinic transmission in pontine areas linked to REM sleep control also influences behavioral arrests, we microinjected neostigmine (50 nl, 62.5 µM) or neostigmine + atropine (62.5 µM and 111 µM respectively) into the nucleus pontis oralis and caudalis. Neostigmine increased the number of arrests in DKO mice without altering arrest lifetimes but did not provoke arrests in WT mice. Co-injection of atropine abolished this effect. Collectively, our findings establish that behavioral arrests in DKO mice are similar to those in orexin deficient mice and that arrests have exponentially distributed lifetimes. We also show, for the first time in a rodent narcolepsy model, that cholinergic systems can regulate arrest dynamics. Since perturbations of muscarinic transmission altered arrest frequency but not lifetime, our findings suggest cholinergic systems influence arrest initiation without influencing circuits that determine arrest duration
The state of the Martian climate
60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes
The SAS Gamma-Ray Spectrometer
A new type of compact high resolution high sensitivity gamma ray spectrometer
for short pulse intense 250 keV to 50 MeV gamma rays has been developed by
combining the principles of scintillators and attenuation spectrometers. The
first prototype of this scintillator attenuation spectrometer or SAS was tested
successfully in Trident laser experiments at LANL. Later versions have been
used extensively in the Texas Petawatt laser experiments in Austin TX, and more
recently in OMEGAEP laser experiments at LLE, Rochester, NY. The SAS is
particularly useful for high repetition rate laser applications. Here we give a
concise description of the design principles, capabilities and sample
preliminary results of the SAS.Comment: Revised version of paper for submission to the Review of Scientific
Instruments. New version has 13 pages and 12 figure
A genome-wide comparison of mesenchymal stem cells derived from human placenta and umbilical cord
Objective: The human umbilical cord and placenta have been considered as attractive alternative sources for noninvasive isolation of human mesenchymal stem cells (hMSCs). Different sources of MSC may have individual differentiation potential and phenotype. In this study, we compared the genome-wide expression data of umbilical cord and placenta derived hMSCs to identify specific differential expression genes (DEGs) and corresponding functions.
Materials and methods: We collected human placental tissues and umbilical cord from healthy full-term placenta (n = 17). The genome-wide gene expression data of hMSCs were used to analyze and compare with that of fibroblasts. We identified the differential expression genes (DEGs) based on the Student's t-test and one-way ANOVA.
Results: According to the DEGs of umbilical cord and placenta, we used the Venn diagram to evaluate the consistence and specific genes. There are 390 umbilical cord specific DEGs which functions are related to movement of sub-cellular component. Then, the DEGs derived from placenta have two major clusters (i.e., placenta-specific (AM-CM-specific) and UC-like (UC-CD-specific)). 247 placenta-specific DEGs are down-regulated and involved in cell communication. 278 UC-like genes are up-regulated and are involved in the cell cycle, cell division, and DNA repair process. Finally, we also identified 239 umbilical cord-placenta consistence DEGs. According to the umbilical cord-placenta consistence DEGs, 175 genes are down-regulated and involved in cell death, cell growth, cell developmental processes.
Conclusion: We identified the consistence and specific DEGs of human placenta and umbilical cord based on the genome-wide comparison. Our results indicated that hMSCs derived from umbilical cord and placenta have different gene expression patterns, and most of specific genes are involved in the cell cycle, cell division, cell death, and cell developmental processes