Most cited article - PubMed ID 32015543
SciPy 1.0: fundamental algorithms for scientific computing in Python
Slipping motions of magnetic field lines are a distinct signature of three-dimensional magnetic reconnection, a fundamental process driving solar and stellar flares. While being a key prediction of numerical experiments, the rapid super-Alfvénic field line slippage driven by the 'slip-running' reconnection has remained elusive in previous observations. New frontiers into exploring transient flare phenomena were introduced by recently designed high cadence observing programs of the Interface Region Imaging Spectrograph (IRIS). By exploiting high temporal resolution imagery (~2 s) of IRIS, here we reveal slipping motions of flare kernels at speeds reaching thousands of kilometres per second. The fast kernel motions are direct evidence of slip-running reconnection in quasi-separatrix layers, regions where magnetic field strongly changes its connectivity. Our results provide observational proof of theoretical predictions unaddressed for nearly two decades and extend the range of magnetic field configurations where reconnection-related phenomena can occur.
- Keywords
- Astrophysical magnetic fields, Astrophysical plasmas, Solar physics,
- Publication type
- Journal Article MeSH
Cellular senescence has recently been recognized as a significant contributor to the poor prognosis of glioblastoma, one of the most aggressive brain tumors. Consequently, effectively eliminating senescent glioblastoma cells could benefit patients. Human ADP/ATP translocases (ANTs) play a role in oxidative phosphorylation in both normal and tumor cells. Previous research has shown that the sensitivity of senescent cells to mitochondria-targeted senolytics depends on the level of ANT2. Here, we systematically mapped the transcript and protein levels of ANT isoforms in various types of senescence and glioblastoma tumorigenesis. We employed bioinformatics analysis, targeted mass spectrometry, RT-PCR, immunoblotting, and assessment of cellular energy state to elucidate how individual ANT isoforms are expressed during the development of senescence in noncancerous and glioblastoma cells. We observed a consistent elevation of ANT1 protein levels across all tested senescence types, while ANT2 and ANT3 exhibited variable changes. Alterations in ANT protein isoform levels correlated with shifts in the cellular oxygen consumption rate. Our findings suggest that ANT isoforms are mutually interchangeable for oxidative phosphorylation and manipulating individual ANT isoforms could have potential for senolytic therapy.
- Keywords
- ADP/ATP translocase, cellular senescence, glioblastoma, targeted mass spectrometry,
- MeSH
- Glioblastoma * pathology genetics metabolism enzymology MeSH
- Isoenzymes metabolism genetics MeSH
- Humans MeSH
- Mitochondrial ADP, ATP Translocases * metabolism genetics MeSH
- Cell Line, Tumor MeSH
- Brain Neoplasms * pathology genetics enzymology metabolism MeSH
- Oxidative Phosphorylation MeSH
- Protein Isoforms metabolism genetics MeSH
- Cellular Senescence * genetics MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Isoenzymes MeSH
- Mitochondrial ADP, ATP Translocases * MeSH
- Protein Isoforms MeSH
OBJECTIVES: To investigate incidence, conversion, neurological characteristics, and age-dependent functional independence of individuals with initial spinal cord injury (SCI) recovering to American Spinal Injury Association Impairment Scale (AIS) E, meaning normal sensory and motor functions according to the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI). METHODS: We analyzed 12,221 EMSCI (European Multicenter Study about Spinal Cord Injury) ISNCSCI datasets from 5 time points over the first year after SCI of 4286 individuals (age: 48.7 ± 19 years; 23% female; 92% traumatic, 8% ischemic). RESULTS: Sixty-five of 82 individuals with at least one AIS E exam had an initial assessment within 6 weeks after injury with neurological level of injury peaking at C4 (16.9%) and L2 (15.4%), predominantly AIS grade D (89.2%), and mean total sensory/motor scores reaching 89.4% of their maximum. First AIS E conversion was detected at a median of 171 (interquartile range 274) days after injury. A change point analysis of Spinal Cord Independence Measure (SCIM) III assessments at the time of conversion of 75 AIS E individuals demonstrates a decline of full functional independence with age particularly over 70 years (<40, 76.9%; 40-70, 42.9%; >70, 14.3%). CONCLUSION: The current AIS E definition insufficiently reflects the reality experienced by older people without deficits in the ISNCSCI, as functional impairments remain predominantly in mobility-related activities. To detect whether these deficits are related to comorbidities attributable to aging rather than remnant deficits of SCI, functional assessments such as the SCIM should be performed in an age-matched non-SCI control group.
- Keywords
- AIS E, American Spinal Injury Association Impairment Scale E, ISNCSCI, SCIM, age, functional independence, spinal cord injury,
- MeSH
- Adult MeSH
- Incidence MeSH
- Middle Aged MeSH
- Humans MeSH
- Recovery of Function * MeSH
- Spinal Cord Injuries * physiopathology rehabilitation epidemiology classification diagnosis MeSH
- Disability Evaluation * MeSH
- Aged MeSH
- Age Factors MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Multicenter Study MeSH
OBJECTIVES: Antimicrobial-resistant bacteria are a major global health threat. Mobile genetic elements (MGEs) have been crucial for spreading resistance to new bacterial species, including human pathogens. Understanding how MGEs promote resistance could be essential for prevention. Here we present an investigation of MGEs and their association with resistance genes in pathogenic bacteria collected from 59 diagnostic units during 2020, representing a snapshot of clinical infections from 35 counties worldwide. METHODS: We analysed 3,095 whole-genome sequenced clinical bacterial isolates from over 100 species to study the relationship between resistance genes and MGEs. The mobiliome of Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Klebsiella pneumoniae were further examined for geographic differences, as these species were prevalent in all countries. Genes potentially mobilized by MGEs were identified by finding DNA segments containing MGEs and ARGs preserved in multiple species. Network analysis was used to investigate potential MGE interactions, host range, and transmission pathways. RESULTS: The prevalence and diversity of MGEs and resistance genes varied among species, with E. coli and S. aureus carrying more diverse elements. MGE composition differed between bacterial lineages, indicating strong vertical inheritance. 102 MGEs associated with resistance were found in multiple species, and four of these elements seemed to be highly transmissible as they were found in different phyla. We identified 21 genomic regions containing resistance genes potentially mobilized by MGEs, highlighting their importance in transmitting genes to clinically significant bacteria. CONCLUSION: Resistance genes are spread through various MGEs, including plasmids and transposons. Our findings suggest that multiple factors influence MGE prevalence and their transposability, thereby shaping the MGE population and transmission pathways. Some MGEs have a wider host range, which could make them more important for mobilizing genes. We also identified 103 resistance genes potentially mobilised by MGEs, which could increase their transmissibility to unrelated bacteria.
- MeSH
- Anti-Bacterial Agents pharmacology MeSH
- Bacteria * genetics drug effects MeSH
- Genes, Bacterial MeSH
- Drug Resistance, Bacterial * genetics MeSH
- Escherichia coli genetics MeSH
- Genome, Bacterial MeSH
- Humans MeSH
- Interspersed Repetitive Sequences * genetics MeSH
- Whole Genome Sequencing MeSH
- Staphylococcus aureus genetics drug effects MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Anti-Bacterial Agents MeSH
PURPOSE: [18F] Poly-ADP-ribose polymerase inhibitors (PARPi), a novel radiotracer, enables visualization of PARP1 upregulation by PET imaging. Here, we aimed to quantify PARPi uptake in tumor lesions of metastatic castration-resistant PCa (mCRPC) patients and perform a comparison with prostate specific membrane antigen (PSMA) expression using PET/CT scans. METHODS: Data from 22 male patients with mCRPC, who underwent [18F]PARPi and [68Ga]Ga-PSMA-11 PET/CT scans, were retrospectively quantified. Lesions with relevant PARPi uptake (higher than background) were delineated and correlated with their [68Ga]PSMA uptake using standardized uptake values (SUV). Additionally, a comparison was performed to investigate the effects of homologous recombination deficiency (HRD) alterations on PARPi tumor uptake. RESULTS: The majority of metastatic PCa lesions that exhibited PARPi uptake were located in the bones (n = 57), with mean SUVmax values of 4.9 ± 1.5 for PARPi and 30.9 ± 28.3 for [68Ga]PSMA. Additionally, 3 local prostate lesions, 14 lymph nodes and 4 further metastatic lesions were detected. Significant correlations were identified between PARPi- and [68Ga]PSMA uptake, as measured by SUVmean (r = 0.48, p < 0.001), SUVpeak (r = 0.48, p < 0.001) and SUVmax (r = 0.43, p < 0.001) of the osseous metastatic lesions and SUVpeak (r = 0.49, p = 0.04) of extraosseous lesions. No significant differences were found between PARPi uptake of metastatic lesions in patients with or without HRD alterations (all p > 0.05). CONCLUSION: Results showed a considerable uptake of [18F]PARPi in mCRPC patients and indicated a correlation between PARPi uptake and PSMA expression, suggesting the potential of using [18F]PARPi as a diagnostic imaging tool in mCRPC patients. More studies are needed to evaluate the clinical benefit of this innovative radiotracer.
- Keywords
- 18F-PARPi, PET/CT, PSMA, Prostate cancer, mCRPC,
- Publication type
- Journal Article MeSH
The biogenesis of mitochondria relies on the import of hundreds of different precursor proteins from the cytosol. Most of these proteins are synthesized with N-terminal presequences which serve as mitochondrial targeting signals. Presequences consistently form amphipathic helices, but they considerably differ with respect to their primary structure and length. Here we show that presequences can be classified into seven different groups based on their specific features. Using a test set of different presequences, we observed that group A presequences endow precursor proteins with improved in vitro import characteristics. We developed IQ-Compete (for Import and de-Quenching Competition assay), a novel assay based on fluorescence de-quenching, to monitor the import efficiencies of mitochondrial precursors in vivo. With this assay, we confirmed the increased import competence of group A presequences. Using mass spectrometry, we found that the presequence of the group A protein Oxa1 specifically recruits the tetratricopeptide repeat (TPR)-containing protein TOMM34 to the cytosolic precursor protein. TOMM34, and the structurally related yeast co-chaperone Cns1, apparently serve as presequence-specific targeting factors which increases the import efficiency of a specific subset of mitochondrial precursor proteins. Our results suggest that presequences contain a protein-specific priority code that encrypts the targeting mechanism of individual mitochondrial precursor proteins.
- MeSH
- Nuclear Proteins MeSH
- Mitochondrial Precursor Protein Import Complex Proteins MeSH
- Mitochondrial Proteins * metabolism genetics MeSH
- Mitochondria * metabolism MeSH
- Protein Precursors metabolism MeSH
- Electron Transport Complex IV MeSH
- Saccharomyces cerevisiae Proteins * metabolism genetics MeSH
- Saccharomyces cerevisiae metabolism MeSH
- Protein Transport MeSH
- Mitochondrial Membrane Transport Proteins metabolism MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Nuclear Proteins MeSH
- Mitochondrial Precursor Protein Import Complex Proteins MeSH
- Mitochondrial Proteins * MeSH
- OXA1 protein MeSH Browser
- Protein Precursors MeSH
- Electron Transport Complex IV MeSH
- Saccharomyces cerevisiae Proteins * MeSH
- Mitochondrial Membrane Transport Proteins MeSH
Phase separation forms membraneless compartments, including heterochromatin "domains" and repair foci. Pericentromeric heterochromatin mostly comprises repeated sequences prone to aberrant recombination. In Drosophila cells, "safe" homologous recombination (HR) repair of these sequences requires their relocalization to the nuclear periphery before Rad51 recruitment and strand invasion. How this mobilization initiates is unknown, and the contribution of phase separation is unclear. Here, we show that Nup98 nucleoporin is recruited to repair sites before relocalization by Sec13 or Nup88, and downstream of the Smc5/6 complex and heterochromatin protein 1 (HP1). Remarkably, Nup98 condensates are immiscible with HP1 condensates, and they are required and sufficient to mobilize repair sites and exclude Rad51, thus preventing aberrant recombination while promoting HR repair. Disrupting this pathway results in heterochromatin repair defects and widespread chromosome rearrangements, revealing an "off-pore" role for nucleoporins and phase separation in nuclear dynamics and genome integrity in a multicellular eukaryote.
- Keywords
- Nup88, Nup98 condensates, Sec13, double-strand break repair, droplets, heterochromatin repair, homologous recombination, nuclear dynamics, nucleoplasmic nucleoporins, phase separation,
- MeSH
- Chromosomal Proteins, Non-Histone metabolism genetics MeSH
- Drosophila melanogaster * genetics metabolism MeSH
- DNA Breaks, Double-Stranded MeSH
- Heterochromatin * genetics metabolism MeSH
- Chromobox Protein Homolog 5 MeSH
- Nuclear Pore Complex Proteins * metabolism genetics MeSH
- Cell Cycle Proteins metabolism genetics MeSH
- Drosophila Proteins * metabolism genetics MeSH
- Recombinational DNA Repair * MeSH
- Rad51 Recombinase * metabolism genetics MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Chromosomal Proteins, Non-Histone MeSH
- Heterochromatin * MeSH
- Chromobox Protein Homolog 5 MeSH
- Nuclear Pore Complex Proteins * MeSH
- nuclear pore complex protein 98 MeSH Browser
- Cell Cycle Proteins MeSH
- Drosophila Proteins * MeSH
- Rad51 Recombinase * MeSH
The perception of a voice in the absence of an external auditory source-an auditory verbal hallucination-is a characteristic symptom of schizophrenia. To better understand this phenomenon requires integration of findings across behavioural, functional, and neurochemical levels. We address this with a locally adapted MEGA-PRESS sequence incorporating interleaved unsuppressed water acquisitions, allowing concurrent assessment of behaviour, blood-oxygenation-level-dependent (BOLD) functional changes, Glutamate + Glutamine (Glx), and GABA, synchronised with a cognitive (flanker) task. We acquired data from the anterior cingulate cortex (ACC) of 51 patients with psychosis (predominantly schizophrenia spectrum disorder) and hallucinations, matched to healthy controls. Consistent with the notion of an excitatory/inhibitory imbalance, we hypothesized differential effects for Glx and GABA between groups, and aberrant dynamics in response to task. Results showed impaired task performance, lower baseline Glx and positive association between Glx and BOLD in patients, contrasting a negative correlation in healthy controls. Task-related increases in Glx were observed in both groups, with no significant difference between groups. No significant effects were observed for GABA. These findings suggest that a putative excitatory/inhibitory imbalance affecting inhibitory control in the ACC is primarily observed as tonic, baseline glutamate differences, rather than GABAergic effects or aberrant dynamics in relation to a task.
- Keywords
- Functional spectroscopy, GABA, Glutamate, Hallucinations, MEGA-PRESS, Psychosis,
- MeSH
- Gyrus Cinguli metabolism physiopathology MeSH
- Adult MeSH
- gamma-Aminobutyric Acid * metabolism MeSH
- Glutamine metabolism MeSH
- Hallucinations * metabolism physiopathology MeSH
- Cognition * physiology MeSH
- Glutamic Acid * metabolism MeSH
- Middle Aged MeSH
- Humans MeSH
- Magnetic Resonance Imaging MeSH
- Young Adult MeSH
- Psychotic Disorders * metabolism physiopathology MeSH
- Case-Control Studies MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Young Adult MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- gamma-Aminobutyric Acid * MeSH
- Glutamine MeSH
- Glutamic Acid * MeSH
Extracellular vesicles (EVs) are membranous particles released by cells and are considered to be promising sources of biomarkers for various diseases. Mass spectrometry (MS) analysis of EVs requires a sample of purified and detergent-lysed EVs. Purification of EVs is laborious, based on size, density, or surface nature, and requires large amounts of the source material (e.g., blood, spinal fluid). We have employed synthetically produced large unilamellar lipid vesicles (LUVs) as analogs of EVs to demonstrate an alternative approach to vesicle separation for subsequent mass spectrometry analysis of their composition. Mass-to-charge ratio m/z separation by frequency-controlled quadrupole was employed to filter narrow-size distributions of LUVs from a water sample. Lipid vesicles were positively charged with nanoelectrospray and transferred into a vacuum using two wide m/z-range frequency-controlled quadrupoles. The m/z, charges, and masses of individual vesicles were obtained by the nondestructive single-pass charge detector. The resolving mode of the second quadrupole with m/z RSD < 10% allowed to separate size selected distributions of vesicles with modal diameters of 88, 112, 130, 162, and 190 nm at corresponding quadrupole m/z settings of 2.5 × 105, 5 × 105, 8 × 105, 1.5 × 106, and 2.5 × 106, respectively with a rate of 20-100 counts per minute. The distributions of bioparticles with masses between 108 and 1010 Da were separated from human blood serum in the pilot experiment. The presented approach for lipid vesicle separation encourages the development of new techniques for the direct mass-spectrometric analysis of biomarkers in MS-separated EVs in a vacuum.
- MeSH
- Extracellular Vesicles * chemistry MeSH
- Mass Spectrometry * methods MeSH
- Humans MeSH
- Unilamellar Liposomes * chemistry analysis isolation & purification MeSH
- Vacuum MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Unilamellar Liposomes * MeSH
CDD plays a pivotal role within the pyrimidine salvage pathway. In this study, a novel, rapid method for the identification of cell lines lacking functional cytidine deaminase was developed. This innovative method utilizes immunocytochemical detection of the product of 5-fluorocytidine deamination, 5-fluorouridine in cellular RNA, enabling the identification of these cells within two hours. The approach employs an anti-bromodeoxyuridine antibody that also specifically binds to 5-fluorouridine and its subsequent detection by a fluorescently labeled antibody. Our results also revealed a strong correlation between the 5-fluorouridine/5-fluorocytidine cytotoxicity ratio and cytidine deaminase content. On the other hand, no correlation was observed between the 5-fluorouridine/5-fluorocytidine cytotoxicity ratio and deoxycytidine monophosphate deaminase content. Similarly, no correlation was observed between this ratio and equilibrative nucleoside transporters 1 or 2. Finally, concentrative nucleoside transporters 1, 2, or 3 also do not correlate with the 5-fluorouridine/5-fluorocytidine cytotoxicity ratio.
- Keywords
- 5-fluorocytidine deamination, 5-fluorouridine, cytidine deaminase, equilibrative and concentrative nucleoside transporters,
- MeSH
- Cell Line MeSH
- Cytidine analogs & derivatives metabolism MeSH
- Cytidine Deaminase * metabolism deficiency genetics MeSH
- Humans MeSH
- Uridine analogs & derivatives metabolism MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- 5-fluorouridine MeSH Browser
- Cytidine MeSH
- Cytidine Deaminase * MeSH
- Uridine MeSH