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We investigated the influence of sex hormones on the expression of α- and β-cardiac myosin heavy chain isoforms (α-MHC and β-MHC) in C57bl/6 mice of both sexes under physiological and pathological conditions. In the left ventricles (LVs) of fertile female mice, β-MHC expression was tenfold higher compared with the age-matched males, whereas no difference was found in α-MHC expression. These differences disappeared after ovariectomy or in immature mice. We also found a sex-related difference in expression of β-adrenoceptors (β1-AR), as mRNA levels of this gene were 40% lower in fertile females compared with males of the same age but did not differ in prepubertal or ovariectomized animals. Interestingly, the deletion of both β1- and β2-ARs abolished sex difference of β-MHC expression, as mRNA levels in the LVs of knockout males were increased and reached values comparable to those of knockout females. Moreover, the β1-AR antagonist metoprolol induced about a threefold increase in β-MHC expression in adult male mice. The capability of gender to regulate β-MHC expression was also evaluated in the presence of hemodynamic overload. Thoracic aortic coarctation (TAC) produced cardiac hypertrophy along with a 12-fold increase in β-MHC and a 50% decrease in β1-AR expression in males but not in females, thus abolishing the gender difference observed in sham animals for such genes. By contrast, TAC did not change β2-AR expression. In conclusion, our results show that the expression of β-MHC and β1-AR in the LVs undergo gender-related and correlated changes under both physiological and pathological conditions and suggest a role of β1-AR-mediated signaling. [ABSTRACT FROM AUTHOR]

An understanding of gas migration along faults is important in many geologic research fields, such as geothermal exploration, risk assessment, and, more recently, the geologic storage of manmade carbon dioxide (CO2). If these gases reach the surface, they typically are discharged to the atmosphere from small areas known as gas vents. In a study of an individual gas vent located in the extinct Latera caldera, central Italy, near-surface geochemical and geophysical surveys were conducted to define the spatial distribution of gas-induced effects in the first few meters of the soil and, by inference, the 3D structure and geometry of the associated gas-permeable fault. Grid surveys and detailed profiles were performed across this vent using time-domain reflectometry (TDR), ground-penetrating radar (GPR), frequency-domain electromagnetics (FDEM), electrical resistivity tomography (ERT), and gas geochemistry measurements. Detailed profile surveys indicate that the leaking CO2 has changed the physical, chemical, and biological soil environment of the vent, resulting in significant spatial variations in parameters (e.g., water content and soil electric/dielectric properties) that influence geophysical measurement results. Despite the strong difference in vertical and lateral resolution and depth of investigation, all methods show the same general trends and similar relative variations in the measured physical parameters. TDR and GPR data highlight anomalous shallow lateral variations, whereas FDEM and ERT measurements identify the vertical extension of the anomalous zone. All methods highlight a north-northwest-south-southeast anomaly alignment that we associate with the main fault; FDEM and, to a lesser extent, CO2 flux also show elongation orthogonal to this direction, implying that the vent may occur at the intersection or two structures. Thus, different near-surface geophysical and geochemical methods can provide important information on faults and their gas-migration characteristics. [ABSTRACT FROM AUTHOR]

Background: Chimeric proteins obtained by the fusion of a G protein-coupled receptor (GPCR) sequence to the N-terminus of the G protein α-subunit have been extensively used to investigate several aspects of GPCR signalling. Although both the receptor and the G protein generally maintain a fully functional state in such polypeptides, original observations made using a chimera between the β2-adrenergic receptor (β 2AR) and Gα s indicated that the fusion to the α-subunit resulted in a marked reduction of receptor desensitization and down-regulation. To further investigate this phenomenon, we have compared the rates of internalization and recycling between wild-type and Gαs fused βsAR. Results: The rate of agonist-induced internalization, measured as the disappearance of cell surface immunofluorescence in HEK293 cells permanently expressing N-terminus tagged receptors, was reduced three-fold by receptor-G protein fusion. However, both fused and non-fused receptors translocated to the same endocytic compartment, as determined by dual-label confocal analysis of cells co-expressing both proteins and transferrin co-localization. Receptor recycling, determined as the reversion of surface immunofluorescence following the addition of antagonist to cells that were previously exposed to agonist, markedly differed between wild-type and fused receptors. While most of the internalized β2AR returned rapidly to the plasma membrane, β2AR-Gα s did not recycle, and the observed slow recovery for the fusion protein immunofluorescence was entirely accounted for by protein synthesis. Conclusion: The covalent linkage between β2AR and Gαs does not appear to alter the initial endocytic translocation of the two proteins, although there is reduced efficiency. It does, however, completely disrupt the process of receptor and G protein recycling. We conclude that the physical separation between receptor and Gα is not necessary for the transit to early endosomes, but is an essential requirement for the correct post-endocytic sorting and recycling of the two proteins. [ABSTRACT FROM AUTHOR]

Growing evidence indicates that cell cycle arrest and neurogenesis are highly coordinated and interactive processes, governed by cell cycle genes and neural transcription factors. The gene PC3 (Tis21/BTG2) is expressed in the neuroblast throughout the neural tube and inhibits cell cycle progression at the G1 checkpoint by repressing cyclin D1 transcription. We generated inducible mouse models in which the expression of PC3 was upregulated in neuronal precursors of the neural tube and of the cerebellum. These mice exhibited a marked increase in the production of postmitotic neurons and impairment of cerebellar development. Cerebellar granule precursors of PC3 transgenic mice displayed inhibition of cyclin D1 expression and a strong increase in the expression of Math1, a transcription factor required for their differentiation. Furthermore, PC3, encoded by a recombinant adenovirus, also induced Math1 in postmitotic granule cells in vitro and stimulated the Math1 promoter activity. In contrast, PC3 expression was unaffected in the cerebellar primordium of Math1 null mice, suggesting that PC3 acts upstream to Mattel. As a whole, our data suggest that cell cycle exit of cerebellar granule cell precursors and the onset of cerebellar neurogenesis are coordinated by PC3 through transcriptional control of cyclin D1 and Math1, respectively. [ABSTRACT FROM AUTHOR]

The relationship between cell pigmentation and radiosensitivity was investigated in a cell model in which melanogenesis was suppressed by a glycosylation inhibitor. It was found that X-irradiation of melanotic B-16 melanoma cells and their amelanotic counterparts, obtained by glucosamine treatment, showed an inverse correlation between radiosensitivity and melanin contents. Since melanogenesis interruption by glucosamine does not affect the DNA repair capacity of nonpigmented cells, it is likely that intracellular melanins play a role in the relative resistance of pigmented cells to X-irradiation. [ABSTRACT FROM AUTHOR]

The measurements of the time domain reflectometry (TDR) signal propagating along a coaxial probe, filled with dry mixtures of glass beads and magnetite, are analyzed for deriving the attenuation factor α and the bandwidth. Samples with different percentages (5%–25%) of magnetite are considered. The α values are obtained by two different methods: (i) wave amplitude at the second reflection, (ii) electromagnetic parameters and widths of the passing bands. The two methods provide consistent α values within the experimental uncertainties. The agreement supports the possibility of measuring the attenuation factor from the second TDR reflection, for anhydrous samples similar to the investigated mixtures. [ABSTRACT FROM AUTHOR]

Liquid water was present on the surface of Mars in the distant past; part of that water is now in the ground in the form of permafrost and heat from the molten interior of the planet could cause it to melt at depth. MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding) has surveyed the Martian subsurface for more than fifteen years in search for evidence of such water buried at depth. Radar detection of liquid water can be stated as an inverse electromagnetic scattering problem, starting from the echo intensity collected by the antenna. In principle, the electromagnetic problem can be modelled as a normal plane wave that propagates through a three-layered medium made of air, ice and basal material, with the final goal of determining the dielectric permittivity of the basal material. In practice, however, two fundamental aspects make the inversion procedure of this apparent simple model rather challenging: (i) the impossibility to use the absolute value of the echo intensity in the inversion procedure; (ii) the impossibility to use a deterministic approach to retrieve the basal permittivity. In this paper, these issues are faced by assuming a priori information on the ice electromagnetic properties and adopting an inversion probabilistic approach. All the aspects that can affect the estimation of the basal permittivity below the Martian South polar cap are discussed and how detection of the presence of basal liquid water was done is described. [ABSTRACT FROM AUTHOR]

Ground Penetrating Radar (GPR) has become an indispensable instrument for high-resolution studies of the shallow subsurface. The non-destructive nature of GPR combined with its excellent depth penetration and rapid deployment over large areas (thereby avoiding time-consuming drilling) has resulted in the extensive and routine application of this technology to fresh water ices. The use of GPR to study sea-ice is, however, much less common, despite its potential to provide valuable information related to, for example, regional effects of global warming. This is because GPR signal propagation in ices with high brine contents is characterized by a lossy behaviour which reduces radar signal penetration. To better understand and quantify this effect we conducted a series of GPR and Vector Network Analyzer (VNA) measurements during freezing at the Sea-ice Environmental Research Facility (SERF), University of Manitoba, Canada. The VNA measurements were performed by using a horizontal, multi-level probe immersed in the water before freezing, which allowed the retrieval of the dielectric properties of sea ice as a function of frequency and depth. The GPR data were collected along multiple transects and grids at different locations in the pool, including in the vicinity of the multi-level probe as well as across targets (steel bars) suspended at different depths below the surface. GPR and VNA data were used to monitor sea ice growth, thus allowing an estimate of the temporal evolution of the ice thickness. Furthermore, the daily measurements of electrical conductivity, extracted from the VNA data, highlighted the relationships between temperature and the evolution of the brine volume-fraction. Our results show that a well calibrated GPR can be employed to monitor the evolution of young sea ice also in critical thermal conditions close to the melting point. [ABSTRACT FROM AUTHOR]

Abstract: Ground-coupled radar has been used in the literature to estimate shallow subsoil permittivity using ground-wave velocity measurements. It has also been shown that the electromagnetic (EM) properties of the soil significantly affect antenna performance, modifying in particular the amplitude, shape, and duration of the ‘early-time’ Ground Penetrating Radar (GPR) signals. To quantitatively evaluate these effects we built a test site consisting of a 4×7×1.2m volume filled primarily with sand; this volume is hydraulically isolated from the surroundings and contains buried pipes in which water can be introduced or removed to control the level of the water table. On a regular grid of 28 points we measured the soil dielectric properties at depth intervals of 0–10 and 0–20cm using Time Domain Reflectometry (TDR) probes, and collected GPR data using both 250 and 500MHz bistatic antennas. The measurements were performed with the water table at different depths to systematically change the shallow-soil dielectric properties. Relative permittivity and conductivity values were calculated from the TDR data, and the average envelopes of the first half cycle of the early-time GPR signals were computed. Data analysis shows a high degree of linear correlation (r≥0.8) between the early-time signal attributes for both antenna frequencies and the EM properties obtained using both TDR probe lengths. The highest correlation (r=0.9) was found between the 500MHz data and the permittivity measured along the 0–20cm depth interval; this relationship is explained in terms of ground wave penetration. The results of our investigation confirm previous field observations and are in full agreement with theoretical predictions and related numerical simulations, highlighting the potential for alternative convenient approaches to predict EM properties of the shallow subsoil. [Copyright &y& Elsevier]

Abstract: Different pathological tau species are involved in memory loss in Alzheimer's disease, the most common cause of dementia among older people. However, little is known about how tau pathology directly affects adult hippocampal neurogenesis, a unique form of structural plasticity implicated in hippocampus-dependent spatial learning and mood-related behavior. To this aim, we generated a transgenic mouse model conditionally expressing a pathological tau fragment (26–230 aa of the longest human tau isoform, or N-tau) in nestin-positive stem/progenitor cells. We found that N-tau reduced the proliferation of progenitor cells in the adult dentate gyrus, reduced cell survival and increased cell death by a caspase-3–independent mechanism, and recruited microglia. Although the number of terminally differentiated neurons was reduced, these showed an increased dendritic arborization and spine density. This resulted in an increase of anxiety-related behavior and an impairment of episodic-like memory, whereas less complex forms of spatial learning remained unaltered. Understanding how pathological tau species directly affect neurogenesis is important for developing potential therapeutic strategies to direct neurogenic instructive cues for hippocampal function repair. [Copyright &y& Elsevier]

Radar sounders are becoming essential methods for the exploration of the Earth, Planets and the interior of small Solar System bodies. The performance of a radar is strongly related to the electromagnetic parameters of the materials composing the body surface and subsurface. Given the very limited access to planetary soil and rocks, meteorites represent important analogues of asteroids and Jovian icy moon crusts. Electromagnetic properties of meteorites are poorly known as they have seldom been investigated through extensive laboratory measurements as a function of frequency, temperature, and density. The present work builds upon a previous study on a solid chondrite sample, extending the measurements to the complex dielectric permittivity and magnetic permeability of a crushed L5 chondrite in the frequency range typical of the radars proposed for future space missions, such as AIDA, JUICE and EUROPA CLIPPER. The results show that for such dry granular materials the main parameter controlling the electromagnetic properties is the sample bulk density. Moreover, our results highlight the importance to account for magnetic properties in radar signal attenuation estimation for planetary exploration. • Electric and magnetic characterization of an L-chondrite granular sample. • Electric permittivity and magnetic permeability dependence on bulk density, temperature and frequency. • Implication for the performance of planetary radar sounders. [ABSTRACT FROM AUTHOR]

Abstract: In this work, the ability of Ground Penetrating Radar (GPR) to detect rocks buried in composite soil is studied in connection with the planned ExoMars mission, as GPR will be used during this mission to scan the Martian subsurface to help define feasible sites for shallow drilling. A realistic model of the operating environment is implemented through a full-wave electromagnetic simulator, taking into account the antenna system and the signal features. The flexibility and efficiency of this numerical approach has allowed for the analysis of a great variety of configurations. The regolith is modeled based on data from recent explorations, while various kinds of embedded rocks are considered that have different geometrical and physical characteristics. The simulated results are compared with ad hoc GPR measurements performed on basalts buried in a mixture of glass beads, as an analogue of a dry sandy Martian soil. A very good agreement between theoretical and experimental results is found, thus validating the proposed numerical approach. This research has defined useful and reliable information concerning the prediction of scattering effects from buried objects in the environment where the ExoMars rover will operate. [Copyright &y& Elsevier]

Abstract: Our aim is to upregulate the expression level of the dystrophin related gene utrophin in Duchenne muscular dystrophy, thus complementing the lack of dystrophin functions. To this end, we have engineered synthetic zinc finger based transcription factors. We have previously shown that the artificial three-zinc finger protein named Jazz fused with the Vp16 activation domain, is able to bind utrophin promoter A and to increase the endogenous level of utrophin in transgenic mice. Here, we report on an innovative artificial protein, named CJ7, that consists of Jazz DNA binding domain fused to a novel activation domain derived from the regulatory multivalent adaptor protein Che-1/AATF. This transcriptional activation domain is 100 amino acids in size and it is very powerful as compared to the Vp16 activation domain. We show that CJ7 protein efficiently promotes transcription and accumulation of the acetylated form of histone H3 on the genomic utrophin promoter locus. [Copyright &y& Elsevier]

Abstract: Recent research has revealed that propranolol, a β-adrenoceptor antagonist, causes extracellular signal-regulated kinase (ERK) cascade activation, nuclear translocation of phospho-ERK and increased transcriptional activity in cultured cell lines. Given the importance of β-adrenoceptor antagonists in the treatment of heart failure, we evaluated the capability of propranolol of promoting the ERK-dependent gene expression at the cardiomyocyte level. To this end, the gene expression of the early growth response factor 1 (Egr1), a well-recognized indicator of nuclear extracellular signal-regulated kinase 1/2 (ERK1/2) activation, was assessed by quantitative real-time RT-PCR in vivo as well as in vitro experiments. Propranolol, administered at the dose of 10 mg/kg/day in C57BL/6 mice, caused a ≈19-fold increase of Egr1 mRNA expression in left ventricular myocardium along with a ≈2.1-fold increase of Egr1 protein expression. Isoproterenol, a nonselective β-adrenoceptor agonist, also increased Egr1 mRNA and protein expression but to a lesser degree. Remarkably, isoproterenol administration was associated with the development of cardiac hypertrophy, whereas propranolol-treated mice showed a completely normal cardiac morphology. The effect of propranolol on Egr1 mRNA expression was abrogated in mice lacking β1- and β2-adrenoceptors indicating that propranolol increases Egr1 mRNA expression in a β-adrenoceptor-dependent manner. The role of β-adrenoceptors was further confirmed by showing that propranolol was able to increase Egr1 mRNA and protein levels in cultured neonatal cardiomyocytes. Collectively, these results indicate that propranolol promotes Egr1 gene expression in cardiomyocytes via β-adrenoceptors with a mechanism which is independent of its ability to antagonize the effects of catecholamines. It is also suggested that cardiomyocyte growth and Egr1 gene overexpression are not obligate processes. [Copyright &y& Elsevier]

Undifferentiated cells and embryos express high levels of endogenous non-telomerase reverse transcriptase (RT) of retroposon/retroviral origin. We previously found that RT inhibitors modulate cell growth and differentiation in several cell lines. We have now sought to establish whether high levels of RT activity are directly linked to cell transformation. To address this possibility, we have employed two different approaches to inhibit RT activity in melanoma and prostate carcinoma cell lines: pharmacological inhibition by two characterized RT inhibitors, nevirapine and efavirenz, and downregulation of expression of RT-encoding LINE-1 elements by RNA interference (RNAi). Both treatments reduced proliferation, induced morphological differentiation and reprogrammed gene expression. These features are reversible upon discontinuation of the anti-RT treatment, suggesting that RT contributes to an epigenetic level of control. Most importantly, inhibition of RT activity in vivo antagonized tumor growth in animal experiments. Moreover, pretreatment with RT inhibitors attenuated the tumorigenic phenotype of prostate carcinoma cells inoculated in nude mice. Based on these data, the endogenous RT can be regarded as an epigenetic regulator of cell differentiation and proliferation and may represent a novel target in cancer therapy.Oncogene (2005) 24, 3923–3931. doi:10.1038/sj.onc.1208562 Published online 4 April 2005 [ABSTRACT FROM AUTHOR]

DNA tumor virus oncoproteins bind and inactivate Rb by interfering with the Rb/HDAC1 interaction. Che-1 is a recently identified human Rb binding protein that inhibits the Rb growth suppressing function. Here we show that Che-1 contacts the Rb pocket region and competes with HDAC1 for Rb binding site, removing HDAC1 from the Rb/E2F complex in vitro and from the E2F target promoters in vivo. Che-1 overexpression activates DNA synthesis in quiescent NIH-3T3 cells through HDAC1 displacement. Consistently, Che-1-specific RNA interference affects E2F activity and cell proliferation in human fibroblasts but not in the pocket protein-defective 293 cells. These findings indicate the existence of a pathway of Rb regulation supporting Che-1 as the cellular counterpart of DNA tumor virus oncoproteins. [Copyright &y& Elsevier]

Modelling regional-scale attenuation of seismic waves at ~1 Hz is challenging, especially when these waves propagate across both continental and oceanic crust. Recent developments in seismic imaging and modelling have provided us with the computational tools necessary to reconstruct these mixed settings using deterministic (coherent) and stochastic (coda) information. Here, we present new tomographic maps of coda-attenuation for both the Italian peninsula and the Tyrrhenian Sea. Kernel-based coda attenuation imaging in the diffusive approximation is tested in the oceanic environment, highlighting a non-diffusive behaviour across the Southern Tyrrhenian Sea. Joint deterministic and Radiative Transfer forward modelling of coherent and scattered waves (Radiative3D) is then performed for the portion of this area showing the lowest coda attenuation. The corresponding parametric study shows that coda attenuation is an efficient marker of variations of Moho depths and crustal reverberations, such as those we observe in a transitional area (characterized by continental crust and thicker Moho) between two oceanic basins (Vavilov and Marsili). Diffusive tomographic imaging informed by Radiative3D modelling reconstructs high-attenuation patterns along the Italian peninsula in agreement with the thick sediments cover across the Po Plain and the Adriatic coast and the magmatic systems in the Central Campanian province. A combined approach of coda-attenuation imaging and modelling can constrain Moho depth and spatial variations of seismic attenuation at regional scale and in mixed continental-oceanic settings. • Imaging and modelling 1 Hz seismic attenuation in a mixed oceanic-continental crust. • Joint coherent and radiative-transfer modelling of seismic envelopes. • Crustal pinches leak direct wave energy into the mantle and increase coda energy. • Shallow Moho must be included in attenuation imaging up to 1 Hz. • High coda attenuation corresponds to high absorption sediments and volcanoes. [ABSTRACT FROM AUTHOR]

Ground Penetrating Radar (GPR) is a terrestrial geophysical exploration method that has recently become one of the most promising technique for planetary, asteroidal and cometary subsurface exploration. The capability of GPR to sound Solar System's bodies relies on the electromagnetic properties of the constitutive materials. Enstatite and ordinary chondrites represent class of asteroids occurring in the inner asteroid belt whereas carbonaceous chondrites and their icy mixtures are reasonable analogues for cometary material as well as constituent of shallow part of some Jovian satellite crusts. Therefore, the knowledge of electromagnetic properties of meteorites is very important because it allows to estimate the radar response in terms of signal velocity and attenuation. In this work we measured the real and imaginary parts of the permittivity of a L5 chondrite meteorite as a function of frequency (20 Hz-1 MHz) by using a capacitive cell connected to a self-balancing bridge. We studied the spatial variability of dielectric properties of the sample that exhibits areas with different textures characterized by a darker appearance. In general, the meteorite sample shows a stronger dispersive behavior compared to terrestrial rocks with higher values for both real and imaginary part of permittivity. In particular, the occurrence of very small grains (<10 μm) of Fe Ni metal, troilite and chromite scattered in some areas of the meteorite seems to be the cause of such behavior. • Dielectric characterization of an L-chondrite solid sample. • Spatial variability in the permittivity due to the presence of metallic phases. • Implication for the performance of planetary radar sounders. [ABSTRACT FROM AUTHOR]

Withdrawal from the cell cycle of differentiating myocytes is regulated by the myogenic basic helix – loop – helix (bHLH) protein MyoD and the pocket proteins pRb, p107 and pRb2/p130. Downstream effectors of `pocket' proteins are the components of the E2F family of transcription factors, which regulate the G1/S-phase transition. We analysed by EMSA the composition of E2F complexes in cycling, quiescent undifferentiated and differentiated C2C12 skeletal muscle cells. An E2F complex containing mainly E2F4 and pRb2/p130 (E2F-G0/G1 complex) appears when DNA synthesis arrests, replacing the cyclinA/cdk2 containing E2F complex of proliferating myoblasts (E2F-G1/S complex). Serum stimulation reinduces DNA synthesis and the re-appearance of E2F-G1/S complexes in quiescent myoblasts but not in differentiated C2C12 myotubes. In differentiating C2C12 cells, E2F complexes switch and DNA synthesis in response to serum are prevented when MyoD DNA binding activity and the cdks inhibitor MyoD downstream effector p21 are induced. Thus, during myogenic differentiation, formation of E2F4 and pRb2/p130 containing complexes is an early event, but not enough on its own to prevent the re-activation of DNA synthesis. Using a subclone of C3H10T1/2 mouse fibroblasts stably expressing Estrogen Receptor-MyoD (ER-MyoD) chimerae, we found that estrogen directed MyoD activation prevents the re-association of cyclinA/cdk2 to the E2F4 containing complex following serum stimulation and this correlates with suppression of E2F activity and the inability of cells to re-enter the cell cycle. Our data indicate that, in differentiating myocytes, one mechanism through which MyoD induces permanent cell cycle arrest involves p21 upregulation and suppression of the proliferation-associated cdks-containing E2F complexes formation. [ABSTRACT FROM AUTHOR]

Two anhydrobiotic strains of the cyanobacterium Chroococcidiopsis, namely CCMEE 029 and CCMEE 171, isolated from the Negev Desert in Israel and from the Dry Valleys in Antarctica, were exposed to salty-ice simulations. The aim of the experiment was to investigate the cyanobacterial capability to survive under sub-freezing temperatures in samples simulating the environment of icy worlds. The two strains were mixed with liquid solutions having sub-eutectic concentration of Na2SO4, MgSO4 and NaCl, then frozen down to different final temperatures (258 K, 233 K and 203 K) in various experimental runs. Both strains survived the exposure to 258 K in NaCl solution, probably as they migrated in the liquid veins between ice grain boundaries. However, they also survived at 258 K in Na2SO4 and MgSO4-salty-ice samples—that is, a temperature well below the eutectic temperature of the solutions, where liquid veins should not exist anymore. Moreover, both strains survived the exposure at 233 K in each salty-ice sample, with CCMEE 171 showing an enhanced survivability, whereas there were no survivors at 203 K. The survival limit at low temperature was further extended when both strains were exposed to 193 K as air-dried cells. The results suggest that vitrification might be a strategy for microbial life forms to survive in potentially habitable icy moons, for example in Europa's icy crust. By entering a dried, frozen state, they could be transported from niches, which became non-habitable to new habitable ones, and possibly return to metabolic activity. [ABSTRACT FROM AUTHOR]