667 research outputs found
Expression of Atrophy mRNA Relates to Tendon Tear Size in Supraspinatus Muscle
Skeletal muscle atrophy and fatty infiltration develop after tendon tearing. The extent of atrophy serves as one prognostic factor for the outcome of surgical repair of rotator cuff tendon tears. We asked whether mRNA of genes involved in regulation of degradative processes leading to muscle atrophy, ie, FOXOs, MSTN, calpains, cathepsins, and transcripts of the ubiquitin-proteasome pathway, are overexpressed in the supraspinatus muscle in patients with and without rotator cuff tears. We evaluated biopsy specimens collected during surgery of 53 consecutive patients with different sizes of rotator cuff tendon tears and six without tears. The levels of corresponding gene transcripts in total RNA extracts were assessed by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. Supraspinatus muscle atrophy was assessed by MRI. The area of muscle tissue (or atrophy), decreased (increased) with increasing tendon tear size. The transcripts of CAPN1, UBE2B, and UBE3A were upregulated more than twofold in massive rotator cuff tears as opposed to smaller tears or patients without tears. These atrophy gene products may be involved in cellular processes that impair functional recovery of affected muscles after surgical rotator cuff repair. However, the damaging effects of gene products in their respective proteolytic processes on muscle structures and proteins remains to be investigate
Molecular response of Deinococcus radiodurans to simulated microgravity explored by proteometabolomic approach
Regarding future space exploration missions and long-term exposure experiments, a detailed
investigation of all factors present in the outer space environment and their effects on organisms of
all life kingdoms is advantageous. Influenced by the multiple factors of outer space, the extremophilic
bacterium Deinococcus radiodurans has been long-termly exposed outside the international Space
Station in frames of the tanpopo orbital mission. the study presented here aims to elucidate molecular
key components in D. radiodurans, which are responsible for recognition and adaptation to simulated
microgravity. D. radiodurans cultures were grown for two days on plates in a fast-rotating 2-D clinostat
to minimize sedimentation, thus simulating reduced gravity conditions. Subsequently, metabolites
and proteins were extracted and measured with mass spectrometry-based techniques. our results
emphasize the importance of certain signal transducer proteins, which showed higher abundances
in cells grown under reduced gravity. these proteins activate a cellular signal cascade, which leads to
differences in gene expressions. Proteins involved in stress response, repair mechanisms and proteins
connected to the extracellular milieu and the cell envelope showed an increased abundance under
simulated microgravity. focusing on the expression of these proteins might present a strategy of cells
to adapt to microgravity conditions
Bacillus subtilis Spore Resistance to Simulated Mars Surface Conditions
In a Mars exploration scenario, knowing if and how highly resistant Bacillus subtilis spores would survive on the Martian surface is crucial to design planetary protection measures and avoid false positives in life-detection experiments. Therefore, in this study a systematic screening was performed to determine whether B. subtilis spores could survive an average day on Mars. For that, spores from two comprehensive sets of isogenic B. subtilis mutant strains, defective in DNA protection or repair genes, were exposed to 24 h of simulated Martian atmospheric environment with or without 8 h of Martian UV radiation [M(+)UV and M(-)UV, respectively]. When exposed to M(+)UV, spore survival was dependent on: (1) core dehydration maintenance, (2) protection of DNA by α/β-type small acid soluble proteins (SASP), and (3) removal and repair of the major UV photoproduct (SP) in spore DNA. In turn, when exposed to M(-)UV, spore survival was mainly dependent on protection by the multilayered spore coat, and DNA double-strand breaks represent the main lesion accumulated. Bacillus subtilis spores were able to survive for at least a limited time in a simulated Martian environment, both with or without solar UV radiation. Moreover, M(-)UV-treated spores exhibited survival rates significantly higher than the M(+)UV-treated spores. This suggests that on a real Martian surface, radiation shielding of spores (e.g., by dust, rocks, or spacecraft surface irregularities) might significantly extend survival rates. Mutagenesis were strongly dependent on the functionality of all structural components with small acid-soluble spore proteins, coat layers and dipicolinic acid as key protectants and efficiency DNA damage removal by AP endonucleases (ExoA and Nfo), non-homologous end joining (NHEJ), mismatch repair (MMR) and error-prone translesion synthesis (TLS). Thus, future efforts should focus on: (1) determining the DNA damage in wild-type spores exposed to M(+/-)UV and (2) assessing spore survival and viability with shielding of spores via Mars regolith and other relevant materials
BioRock:new experiments and hardware to investigate microbe–mineral interactions in space
In this paper, we describe the development of an International Space Station experiment,
BioRock. The purpose of this experiment is to investigate biofilm formation and microbe–mineral
interactions in space. The latter research has application in areas as diverse as regolith amelioration and
extraterrestrial mining. We describe the design of a prototype biomining reactor for use in space
experimentation and investigations on in situ Resource Use and we describe the results of pre-flight tests
Quantum Cryptography
Quantum cryptography could well be the first application of quantum mechanics
at the individual quanta level. The very fast progress in both theory and
experiments over the recent years are reviewed, with emphasis on open questions
and technological issues.Comment: 55 pages, 32 figures; to appear in Reviews of Modern Physic
Microbial interaction with terrestrial and extraterrestrial rocks on the International Space Station
As space agencies plan to expand human presence in space and to settle on the Moon first and Mars later, developing strategies to achieve this goal in a sustainable way is necessary. These include in situ resource utilization (ISRU) and recovering of materials by waste recycling (1). Microbe based technologies may be pivotal to the success of human space exploration. Potential roles of microorganisms in space include manufacturing, as building blocks of ecosystems, in waste recycling and in biomining (2). Understanding microbial response to space conditions is therefore essential to harness their potential. [...
Oxide‐Based Solid‐State Batteries: A Perspective on Composite Cathode Architecture
The garnet-type phase LiLaZrO (LLZO) attracts significant attention as an oxide solid electrolyte to enable safe and robust solid-state batteries (SSBs) with potentially high energy density. However, while significant progress has been made in demonstrating compatibility with Li metal, integrating LLZO into composite cathodes remains a challenge. The current perspective focuses on the critical issues that need to be addressed to achieve the ultimate goal of an all-solid-state LLZO-based battery that delivers safety, durability, and pack-level performance characteristics that are unobtainable with state-of-the-art Li-ion batteries. This perspective complements existing reviews of solid/solid interfaces with more emphasis on understanding numerous homo- and heteroionic interfaces in a pure oxide-based SSB and the various phenomena that accompany the evolution of the chemical, electrochemical, structural, morphological, and mechanical properties of those interfaces during processing and operation. Finally, the insights gained from a comprehensive literature survey of LLZO–cathode interfaces are used to guide efforts for the development of LLZO-based SSBs
No Effect of Microgravity and Simulated Mars Gravity on Final Bacterial Cell Concentrations on the International Space Station: Applications to Space Bioproduction
Microorganisms perform countless tasks on Earth and they are expected to be essential
for human space exploration. Despite the interest in the responses of bacteria to space
conditions, the findings on the effects of microgravity have been contradictory, while
the effects of Martian gravity are nearly unknown. We performed the ESA BioRock
experiment on the International Space Station to study microbe-mineral interactions in
microgravity, simulated Mars gravity and simulated Earth gravity, as well as in ground
gravity controls, with three bacterial species: Sphingomonas desiccabilis, Bacillus
subtilis, and Cupriavidus metallidurans. To our knowledge, this was the first experiment
to study simulated Martian gravity on bacteria using a space platform. Here, we tested
the hypothesis that different gravity regimens can influence the final cell concentrations
achieved after a multi-week period in space. Despite the different sedimentation rates
predicted, we found no significant differences in final cell counts and optical densities
between the three gravity regimens on the ISS. This suggests that possible gravityrelated effects on bacterial growth were overcome by the end of the experiment. The
results indicate that microbial-supported bioproduction and life support systems can be
effectively performed in space (e.g., Mars), as on Earth
Heterochromatin diversity and its co-localization with 5S and 45S rDNA sites in chromosomes of four Maxillaria species (Orchidaceae)
Microbially-Enhanced Vanadium Mining and Bioremediation Under Micro- and Mars Gravity on the International Space Station
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