Neuroprotection of dopamine neurons by xenon against low-level excitotoxic insults is not reproduced by other noble gases

AbstractUsing midbrain cultures, we previously demonstrated that the noble gas xenon is robustly protective for dopamine (DA) neurons exposed to l-trans-pyrrolidine-2,4-dicarboxylate (PDC), an inhibitor of glutamate uptake used to generate sustained, low-level excitotoxic insults. DA cell rescue was observed in conditions where the control atmosphere for cell culture was substituted with a gas mix, comprising the same amount of oxygen (20%) and carbon dioxide (5%) but 75% of xenon instead of nitrogen. In the present study, we first aimed to determine whether DA cell rescue against PDC remains detectable when concentrations of xenon are progressively reduced in the cell culture atmosphere. Besides, we also sought to compare the effect of xenon to that of other noble gases, including helium, neon and krypton. Our results show that the protective effect of xenon for DA neurons was concentration-dependent with an IC50 estimated at about 44%. We also established that none of the other noble gases tested in this study protected DA neurons from PDC-mediated insults. Xenon’s effectiveness was most probably due to its unique capacity to block NMDA glutamate receptors. Besides, mathematical modeling of gas diffusion in the culture medium revealed that the concentration reached by xenon at the cell layer level is the highest of all noble gases when neurodegeneration is underway. Altogether, our data suggest that xenon may be of potential therapeutic value in Parkinson disease, a chronic neurodegenerative condition where DA neurons appear vulnerable to slow excitotoxicity.

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On Noble Gas Anomalies in the Great Namaqualand Troilite

Zeitschrift für Naturforschung A ◽

10.1515/zna-1968-0905 ◽

1968 ◽

Vol 23 (9) ◽

pp. 1266-1271 ◽

Cited By ~ 2

Author(s):

E. C. Alexander ◽

J. H. Bennett ◽

O. K. Manuel

Keyword(s):

Neutron Activation ◽

Isotopic Composition ◽

Neutron Capture ◽

Noble Gases ◽

Noble Gas ◽

Helium Neon

The abundances and isotopic composition of the stable noble gases were measured in a troilite nodule from the Great Namaqualand fine octahedrite. Helium, neon and argon show a significant spallation component. The major anomalies in krypton and xenon are from neutron capture on selenium and tellurium and from the decay of extinct I129. The abundances of tellurium, iodine and uranium in the troilite were determined by neutron activation analyses and compared with the xenon anomalies. The results indicate that part of the excess Xe129 is from neutron capture on tellurium and the remainder is due to the retention of radiogenic Xe129 from the decay of extinct I129, about 200 million years after an initial I129/I127 = 3 × 10-3.

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Noble Gases: A Record of Earth's Evolution and Mantle Dynamics

Annual Review of Earth and Planetary Sciences ◽

10.1146/annurev-earth-053018-060238 ◽

2019 ◽

Vol 47 (1) ◽

pp. 389-419 ◽

Cited By ~ 18

Author(s):

Sujoy Mukhopadhyay ◽

Rita Parai

Keyword(s):

Noble Gases ◽

Noble Gas ◽

Isotopic Ratios ◽

Mantle Structure ◽

Mantle Dynamics ◽

Mid Ocean Ridge ◽

Giant Impacts ◽

Ocean Ridge ◽

Helium Neon

Noble gases have played a key role in our understanding of the origin of Earth's volatiles, mantle structure, and long-term degassing of the mantle. Here we synthesize new insights into these topics gained from high-precision noble gas data. Our analysis reveals new constraints on the origin of the terrestrial atmosphere, the presence of nebular neon but chondritic krypton and xenon in the mantle, and a memory of multiple giant impacts during accretion. Furthermore, the reservoir supplying primordial noble gases to plumes appears to be distinct from the mid-ocean ridge basalt (MORB) reservoir since at least 4.45 Ga. While differences between the MORB mantle and plume mantle cannot be explained solely by recycling of atmospheric volatiles, injection and incorporation of atmospheric-derived noble gases into both mantle reservoirs occurred over Earth history. In the MORB mantle, the atmospheric-derived noble gases are observed to be heterogeneously distributed, reflecting inefficient mixing even within the vigorously convecting MORB mantle. ▪ Primordial noble gases in the atmosphere were largely derived from planetesimals delivered after the Moon-forming giant impact. ▪ Heterogeneities dating back to Earth's accretion are preserved in the present-day mantle. ▪ Mid-ocean ridge basalts and plume xenon isotopic ratios cannot be related by differential degassing or differential incorporation of recycled atmospheric volatiles. ▪ Differences in mid-ocean ridge basalts and plume radiogenic helium, neon, and argon ratios can be explained through the lens of differential long-term degassing.

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Noble Gases Deliver Cool Dates from Hot Rocks

Elements ◽

10.2138/gselements.16.5.303 ◽

2020 ◽

Vol 16 (5) ◽

pp. 303-309 ◽

Cited By ~ 6

Author(s):

Cécile Gautheron ◽

Peter K. Zeitler

Keyword(s):

Heat Transfer ◽

Fluid Flow ◽

Solid Earth ◽

Noble Gases ◽

Noble Gas ◽

Radioactive Decay ◽

Gas Diffusion ◽

Clear Signature ◽

Inverse Models ◽

Thermal Histories

Heat transfer in the solid Earth drives processes that modify temperatures, leaving behind a clear signature that we can measure using noble gas thermochronology. This allows us to record the thermal histories of rocks and obtain the timing, rate, and magnitude of phenomena such as erosion, deformation, and fluid flow. This is done by measuring the net balance between the accumulation of noble gas atoms from radioactive decay and their loss by temperature-activated diffusion in mineral grains. Together with knowledge about noble gas diffusion in common minerals, we can then use inverse models of this accumulation–diffusion balance to recover thermal histories. This approach is now a mainstream method by which to study geodynamics and Earth evolution.

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Liquid noble gases for dark matter searches: An updated survey

International Journal of Modern Physics A ◽

10.1142/s0217751x15300537 ◽

2015 ◽

Vol 30 (26) ◽

pp. 1530053 ◽

Cited By ~ 9

Author(s):

R. Bernabei ◽

P. Belli ◽

A. Incicchitti ◽

F. Cappella ◽

R. Cerulli

Keyword(s):

Dark Matter ◽

Noble Gases ◽

Noble Gas ◽

Low Energy ◽

Gas Detectors ◽

Double Phase ◽

Methodological Comparison ◽

Direct Dark Matter ◽

Energy Physics

An updated technical and methodological comparison of liquid noble gas experiments is presented with particular attention to the low energy physics application of double-phase noble gas detectors in direct Dark Matter investigations.

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Emission of Noble Gases Binary Mixtures under Excitation by the Products of the 6Li (n, α)3 H Nuclear Reaction

Science and Technology of Nuclear Installations ◽

10.1155/2020/8891891 ◽

2020 ◽

Vol 2020 ◽

pp. 1-7

Author(s):

Kuanysh Samarkhanov ◽

Mendykhan Khasenov ◽

Erlan Batyrbekov ◽

Inesh Kenzhina ◽

Yerzhan Sapatayev ◽

...

Keyword(s):

Nuclear Reaction ◽

Nuclear Energy ◽

Alkali Metals ◽

Nuclear Reactor ◽

Noble Gases ◽

Noble Gas ◽

Direct Conversion ◽

Reaction Products ◽

Gas Molecules ◽

Sodium And Potassium

The luminescence of Kr-Xe, Ar-Kr, and Ar-Xe mixtures was studied in the spectral range 300–970 nm when excited by 6Li (n, α)3 H nuclear reaction products in the core of a nuclear reactor. Lithium was deposited on walls of experimental cell in the form of a capillary-porous structure, which made it possible to measure up to a temperature of 730 K. The temperature dependence of the radiation intensity of noble gas atoms, alkali metals, and heteronuclear ionic noble gas molecules was studied. Also, as in the case of single-component gases, the appearance of lithium lines and impurities of sodium and potassium is associated with vaporization during the release of nuclear reaction products from the lithium layer. The excitation of lithium atoms occurs mainly as a result of the Penning process of lithium atoms on noble gas atoms in the 1s states and subsequent ion-molecular reactions. Simultaneous radiation at transitions of atoms of noble gases and lithium, heteronuclear ion molecules of noble gases allows us to increase the efficiency of direct conversion of nuclear energy into light.

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Leading Interaction Components in the Structure and Reactivity of Noble Gases Compounds

Molecules ◽

10.3390/molecules25102367 ◽

2020 ◽

Vol 25 (10) ◽

pp. 2367

Author(s):

Francesca Nunzi ◽

Giacomo Pannacci ◽

Francesco Tarantelli ◽

Leonardo Belpassi ◽

David Cappelletti ◽

...

Keyword(s):

Chemical Bond ◽

Theoretical Approach ◽

Noble Gases ◽

Halogen Bond ◽

Noble Gas ◽

Anomalous Behavior ◽

Type Interaction ◽

Long Life ◽

Weak Chemical

The nature, strength, range and role of the bonds in adducts of noble gas atoms with both neutral and ionic partners have been investigated by exploiting a fine-tuned integrated phenomenological–theoretical approach. The identification of the leading interaction components in the noble gases adducts and their modeling allows the encompassing of the transitions from pure noncovalent to covalent bound aggregates and to rationalize the anomalous behavior (deviations from noncovalent type interaction) pointed out in peculiar cases. Selected adducts affected by a weak chemical bond, as those promoting the formation of the intermolecular halogen bond, are also properly rationalized. The behavior of noble gas atoms excited in their long-life metastable states, showing a strongly enhanced reactivity, has been also enclosed in the present investigation.

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Noble Gases in Terrestrial Planets: Evidence for Cometary Impacts?

International Astronomical Union Colloquium ◽

10.1017/s0252921100109789 ◽

1989 ◽

Vol 116 (1) ◽

pp. 429-437

Author(s):

Tobias Owen ◽

Akiva Bar-Nun ◽

Idit Kleinfeld

Keyword(s):

Low Temperatures ◽

Noble Gases ◽

Noble Gas ◽

Terrestrial Planets ◽

Laboratory Studies ◽

The Impact ◽

Gas Patterns ◽

Atmosphere Of Venus

AbstractThe possible role of comets in bringing volatiles to the inner planets is investigated by means of laboratory studies of the ability of ice to trap gases at low temperatures. The pattern of the heavy noble gases formed in the atmosphere of Venus can be explained by the impact of a planetesimal composed of ices formed in the range of 20 to 30 K. The noble gas patterns on Mars and Earth are less explicable by cometary bombardment alone.

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