scholarly journals Hibernation and Radioprotection: Gene Expression in the Liver and Testicle of Rats Irradiated under Synthetic Torpor

2019 ◽  
Vol 20 (2) ◽  
pp. 352 ◽  
Author(s):  
Walter Tinganelli ◽  
Timna Hitrec ◽  
Fabrizio Romani ◽  
Palma Simoniello ◽  
Fabio Squarcio ◽  
...  
Keyword(s):  
Ataxia Telangiectasia ◽  
Histological Analysis ◽  
Space Exploration ◽  
Space Travel ◽  
X Rays ◽  
Ataxia Telangiectasia Mutated ◽  
Dna Damage Signaling ◽  
Reduced Toxicity ◽  
First Time

Hibernation has been proposed as a tool for human space travel. In recent years, a procedure to induce a metabolic state known as “synthetic torpor” in non-hibernating mammals was successfully developed. Synthetic torpor may not only be an efficient method to spare resources and reduce psychological problems in long-term exploratory-class missions, but may also represent a countermeasure against cosmic rays. Here we show the preliminary results from an experiment in rats exposed to ionizing radiation in normothermic conditions or synthetic torpor. Animals were irradiated with 3 Gy X-rays and organs were collected 4 h after exposure. Histological analysis of liver and testicle showed a reduced toxicity in animals irradiated in torpor compared to controls irradiated at normal temperature and metabolic activity. The expression of ataxia telangiectasia mutated (ATM) in the liver was significantly downregulated in the group of animal in synthetic torpor. In the testicle, more genes involved in the DNA damage signaling were downregulated during synthetic torpor. These data show for the first time that synthetic torpor is a radioprotector in non-hibernators, similarly to natural torpor in hibernating animals. Synthetic torpor can be an effective strategy to protect humans during long term space exploration of the solar system.

scholarly journals Exposure of the cytoplasm to low-dose X-rays modifies ataxia telangiectasia mutated-mediated DNA damage responses

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Munetoshi Maeda ◽  
Masanori Tomita ◽  
Mika Maeda ◽  
Hideki Matsumoto ◽  
Noriko Usami ◽  
...  
Keyword(s):  
Dna Damage ◽  
Cell Death ◽  
Ataxia Telangiectasia ◽  
Kinase Inhibitor ◽  
Surrogate Marker ◽  
X Rays ◽  
Ataxia Telangiectasia Mutated ◽  
Whole Cell ◽  
X Ray ◽  
Dna Damage Responses

AbstractWe recently showed that when a low X-ray dose is used, cell death is enhanced in nucleus-irradiated compared with whole-cell-irradiated cells; however, the role of the cytoplasm remains unclear. Here, we show changes in the DNA damage responses with or without X-ray microbeam irradiation of the cytoplasm. Phosphorylated histone H2AX foci, a surrogate marker for DNA double-strand breaks, in V79 and WI-38 cells are not observed in nucleus irradiations at ≤ 2 Gy, whereas they are observed in whole-cell irradiations. Addition of an ataxia telangiectasia mutated (ATM) kinase inhibitor to whole-cell irradiations suppresses foci formation at ≤ 2 Gy. ABL1 and p73 expression is upregulated following nucleus irradiation, suggesting the induction of p73-dependent cell death. Furthermore, CDKN1A (p21) is upregulated following whole-cell irradiation, indicating the induction of cell cycle arrest. These data reveal that cytoplasmic radioresponses modify ATM-mediated DNA damage responses and determine the fate of cells irradiated at low doses.

scholarly journals Acute blue finger syndrome: a rare benign cause of acute digit discolouration

2019 ◽  
Vol 12 (1) ◽  
pp. e223365
Author(s):  
Kiran Dhaliwal ◽  
Colin Thomas Brewster ◽  
Sivarajasingham Pakeerathan
Keyword(s):  
Rapid Assessment ◽  
Middle Finger ◽  
X Rays ◽  
Benign Condition ◽  
Volar Aspect ◽  
History Of ◽  
The Right ◽  
Digital Ischaemia ◽  
First Time

Acute blue finger syndrome is a rare benign condition that mimics digital ischaemia. We discuss the case of a 32-year-old woman who presented with a 6hour history of blue discolouration of the middle finger of the right hand, associated with pain and swelling. There was no history of trauma and this was the first time that the patient had experienced these symptoms. Examination found blue discolouration of the digit primarily on the volar aspect with associated swelling. All investigations, including blood tests, X-rays and Doppler scanning, were normal. The symptoms resolved spontaneously within 48 hours. There were no recurrent episodes or long-term sequelae. Patients presenting with an acutely blue finger need rapid assessment to exclude digit ischaemia. Knowledge of this rare benign condition may prevent unnecessary distress, invasive investigations and potentially harmful treatment of a healthy patient.

scholarly journals B Cell-Specific Expression of Ataxia-Telangiectasia Mutated Protein Kinase Promotes Chronic Gammaherpesvirus Infection

2017 ◽  
Vol 91 (19) ◽  
Author(s):  
Eric J. Darrah ◽  
Joseph M. Kulinski ◽  
Wadzanai P. Mboko ◽  
Gang Xin ◽  
Laurent P. Malherbe ◽  
...  
Keyword(s):  
B Cells ◽  
B Cell ◽  
Ataxia Telangiectasia ◽  
Chronic Infection ◽  
Viral Latency ◽  
Viral Reactivation ◽  
Ataxia Telangiectasia Mutated

ABSTRACT Manipulation of host cellular pathways is a strategy employed by gammaherpesviruses, including mouse gammaherpesvirus 68 (MHV68), in order to negotiate a chronic infection. Ataxia-telangiectasia mutated (ATM) plays a unique yet incompletely understood role in gammaherpesvirus infection, as it has both proviral and antiviral effects. Chronic gammaherpesvirus infection is poorly controlled in a host with global ATM insufficiency, whether the host is a mouse or a human. In contrast, ATM facilitates replication, reactivation, and latency establishment of several gammaherpesviruses in vitro, suggesting that ATM is proviral in the context of infected cell cultures. The proviral role of ATM is also evident in vivo, as myeloid-specific ATM expression facilitates MHV68 reactivation during the establishment of viral latency. In order to better understand the complex relationship between host ATM and gammaherpesvirus infection, we depleted ATM specifically in B cells, a cell type critical for chronic gammaherpesvirus infection. B cell-specific ATM deficiency attenuated the establishment of viral latency due to compromised differentiation of ATM-deficient B cells. Further, we found that during long-term infection, peritoneal B-1b, but not related B-1a, B cells display the highest frequency of gammaherpesvirus infection. While ATM expression did not affect gammaherpesvirus tropism for B-1 B cells, B cell-specific ATM expression was necessary to support viral reactivation from peritoneal cells during long-term infection. Thus, our study reveals a role of ATM as a host factor that promotes chronic gammaherpesvirus infection of B cells. IMPORTANCE Gammaherpesviruses infect a majority of the human population and are associated with cancer, including B cell lymphomas. ATM is a unique host kinase that has both proviral and antiviral roles in the context of gammaherpesvirus infection. Further, there is insufficient understanding of the interplay of these roles in vivo during chronic infection. In this study, we show that ATM expression by splenic B cells is required for efficient establishment of gammaherpesvirus latency. We also show that ATM expression by peritoneal B cells is required to facilitate viral reactivation during long-term infection. Thus, our study defines a proviral role of B cell-specific ATM expression during chronic gammaherpesvirus infection.

scholarly journals Energy Storage in Earth-Abundant Dolomite Minerals

2020 ◽  
Vol 10 (19) ◽  
pp. 6679
Author(s):  
Sesha Srinivasan ◽  
Dominic Dodson ◽  
Mc Ben Joe Charles ◽  
Scott L. Wallen ◽  
Gary Albarelli ◽  
...  
Keyword(s):  
Energy Storage ◽  
X Rays ◽  
High Concentration ◽  
Earth Abundant ◽  
Calcium Magnesium ◽  
Automated Mineralogy ◽  
Carbon Dioxide Co2 ◽  
Automated Scanning ◽  
First Time

Dolomite, a calcium magnesium mineral (CaMg(CO3)2), is considered an undesirable accompanying mineral in the phosphoric acid production process and, as such, large quantities of this mineral are available in Florida. This study is aimed toward the characterization of the high-concentration phosphatic dolomite pebbles (handpicked dolomites) received from the Florida Industrial and Phosphate Research Institute (FIPR) and investigate their feasibility for thermochemical energy storage (TCES). The chemical composition, structural and microstructural characteristics of commercial and handpicked dolomite minerals was studied using a variety of techniques such as X-ray Fluorescence (XRF), Fourier-transform infrared spectroscopy (FTIR), and an automated mineralogy Automated SEM-EDX Mineralogy (or automated scanning electron microscopy) with energy dispersive X-rays spectrometer (SEM-EDX), which confirmed the phosphatic pebbles received contains dolomite (CaMg(CO3)2) phase in a high percentage. Particle size and the surface area were measured using XRD and N2 adsorption, the Brunauer–Emmett–Teller (BET) methods. Thermogravimetric analysis (TGA) was used to determine the activation energy for the calcination and re-carbonation reactions of the dolomite pebbles in nitrogen (N2) and carbon dioxide (CO2) atmospheres at temperatures up to 800 °C. The present results exhibit, for the first time, the potential for using abundant, high phosphatic concentration dolomite possessing long-term cycling behavior for thermochemical energy storage applications in Concentrated Solar Power (CSP) plants.

scholarly journals Elevated Ornithine Decarboxylase Levels Activate Ataxia Telangiectasia Mutated–DNA Damage Signaling in Normal Keratinocytes

2008 ◽  
Vol 68 (7) ◽  
pp. 2214-2222 ◽  
Author(s):  
Gang Wei ◽  
Karen DeFeo ◽  
Candace S. Hayes ◽  
Patrick M. Woster ◽  
Laura Mandik-Nayak ◽  
...  
Keyword(s):  
Dna Damage ◽  
Ornithine Decarboxylase ◽  
Ataxia Telangiectasia ◽  
Ataxia Telangiectasia Mutated ◽  
Dna Damage Signaling ◽  
Normal Keratinocytes

scholarly journals Spectral Modeling of Flares in Long-term Gamma-Ray Light Curve of PKS 0903-57

2021 ◽  
Vol 922 (2) ◽  
pp. 160
Author(s):  
Sandeep Kumar Mondal ◽  
Raj Prince ◽  
Nayantara Gupta ◽  
Avik Kumar Das
Keyword(s):  
Gamma Ray ◽  
Spectral Energy ◽  
Emission Region ◽  
Multiple Time ◽  
Emission Model ◽  
X Rays ◽  
Large Area ◽  
Bl Lacertae ◽  
First Time

Abstract A detailed study of the BL Lacertae PKS 0903-57 has been done for the first time with 12 yr of Fermi Large Area Telescope data. We have identified two bright gamma-ray flares in 2018 and 2020. Many substructures were observed during multiple time binning of these flares. We performed a detailed temporal and spectral study on all the substructures separately. A single-zone emission model is used for time-dependent leptonic modeling of the multiwavelength spectral energy distributions. Our estimated values of variability timescale, magnetic field in the emission region, and the jet power obtained from leptonic modeling of PKS 0903-57 are presented in this work. Currently, we have a minimal number of observations in X-rays and other bands. Hence, further simultaneous multiwavelength monitoring of this source is required to have a better understanding of the physical processes occurring in the jet of the blazar PKS 0903-57.

scholarly journals Mammal survival at the Cretaceous–Palaeogene boundary: metabolic homeostasis in prolonged tropical hibernation in tenrecs

2014 ◽  
Vol 281 (1796) ◽  
pp. 20141304 ◽  
Author(s):  
Barry G. Lovegrove ◽  
Kerileigh D. Lobban ◽  
Danielle L. Levesque
Keyword(s):  
Temperature Dependence ◽  
Space Exploration ◽  
Space Travel ◽  
Deep Space ◽  
Meteorite Impact ◽  
Long Period ◽  
Dominant Feature ◽  
Free Ranging ◽  
Mammalian Hibernation

Free-ranging common tenrecs, Tenrec ecaudatus , from sub-tropical Madagascar, displayed long-term (nine months) hibernation which lacked any evidence of periodic interbout arousals (IBAs). IBAs are the dominant feature of the mammalian hibernation phenotype and are thought to periodically restore long-term ischaemia damage and/or metabolic imbalances (depletions and accumulations). However, the lack of IBAs in tenrecs suggests no such pathology at hibernation T b s > 22°C. The long period of tropical hibernation that we report might explain how the ancestral placental mammal survived the global devastation that drove the dinosaurs and many other vertebrates to extinction at the Cretaceous–Palaeogene boundary following a meteorite impact. The genetics and biochemistry of IBAs are of immense interest to biomedical researchers and space exploration scientists, in the latter case, those envisioning a hibernating state in astronauts for deep space travel. Unravelling the physiological thresholds and temperature dependence of IBAs will provide new impetus to these research quests.

Somatic Embryogenesis and In vitro Plant Regeneration in Vigna trilobata (L.) Verd. - A Potential Pasture Legume

1970 ◽  
Vol 19 (1) ◽  
pp. 89-99
Author(s):  
K. Choudhary ◽  
M. Singh ◽  
M. S. Rathore ◽  
N. S. Shekhawat
Keyword(s):  
Somatic Embryogenesis ◽  
Growth Regulators ◽  
Somatic Embryos ◽  
Basal Medium ◽  
Long Term Study ◽  
Continuous Application ◽  
First Time ◽  
Pasture Legume

This long term study demonstrates for the first time that it is possible to propagate embryogenic Vigna trilobata and to subsequently initiate the differentiation of embryos into complete plantlets. Initiation of callus was possible on 2,4-D. Somatic embryos differentiated on modified MS basal nutrient medium with 1.0 mg/l  of 2,4-D and 0.5 mg/l  of Kn. Sustained cell division resulted in globular and heart shape stages of somatic embryos. Transfer of embryos on to a fresh modified MS basal medium with 0.5 mg/l of Kn and 0.5 mg/l of GA3 helped them to attain maturation and germination. However, the propagation of cells, as well as the differentiation of embryos, were inhibited by a continuous application of these growth regulators. For this reason, a long period on medium lacking these growth regulators was necessary before the differentiation of embryos occurred again. The consequences for improving the propagation of embryogenic cultures in Vigna species are discussed. Key words: Pasture  legume, Vigna trilobata, Globular, Heart shape, somatic embryogenesis D.O.I. 10.3329/ptcb.v19i1.4990 Plant Tissue Cult. & Biotech. 19(1): 89-99, 2009 (June)

Sign in / Sign up

Export Citation Format

Share Document