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  1. Article ; Online: Microsynt: Exploring the syntax of EEG microstates.

    Artoni, Fiorenzo / Maillard, Julien / Britz, Juliane / Brunet, Denis / Lysakowski, Christopher / Tramèr, Martin R / Michel, Christoph M

    NeuroImage

    2023  Volume 277, Page(s) 120196

    Abstract: ... to be attracted towards "A - B - C" microstate hubs, and most prominently A - B binary loops. Conversely ... with full unconsciousness, sequences of microstates are attracted towards "C - D - E" hubs, and most ... prominently C - E binary loops, confirming the putative relation of microstates A and B to externally-oriented ...

    Abstract Microstates represent electroencephalographic (EEG) activity as a sequence of switching, transient, metastable states. Growing evidence suggests the useful information on brain states is to be found in the higher-order temporal structure of these sequences. Instead of focusing on transition probabilities, here we propose "Microsynt", a method designed to highlight higher-order interactions that form a preliminary step towards understanding the syntax of microstate sequences of any length and complexity. Microsynt extracts an optimal vocabulary of "words" based on the length and complexity of the full sequence of microstates. Words are then sorted into classes of entropy and their representativeness within each class is statistically compared with surrogate and theoretical vocabularies. We applied the method on EEG data previously collected from healthy subjects undergoing propofol anesthesia, and compared their "fully awake" (BASE) and "fully unconscious" (DEEP) conditions. Results show that microstate sequences, even at rest, are not random but tend to behave in a more predictable way, favoring simpler sub-sequences, or "words". Contrary to high-entropy words, lowest-entropy binary microstate loops are prominent and favored on average 10 times more than what is theoretically expected. Progressing from BASE to DEEP, the representation of low-entropy words increases while that of high-entropy words decreases. During the awake state, sequences of microstates tend to be attracted towards "A - B - C" microstate hubs, and most prominently A - B binary loops. Conversely, with full unconsciousness, sequences of microstates are attracted towards "C - D - E" hubs, and most prominently C - E binary loops, confirming the putative relation of microstates A and B to externally-oriented cognitive processes and microstate C and E to internally-generated mental activity. Microsynt can form a syntactic signature of microstate sequences that can be used to reliably differentiate two or more conditions.
    MeSH term(s) Humans ; Electroencephalography ; Brain ; Brain Mapping ; Wakefulness ; Propofol
    Chemical Substances Propofol (YI7VU623SF)
    Language English
    Publishing date 2023-06-05
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1147767-2
    ISSN 1095-9572 ; 1053-8119
    ISSN (online) 1095-9572
    ISSN 1053-8119
    DOI 10.1016/j.neuroimage.2023.120196
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: EEG microstate dynamics indicate a U-shaped path to propofol-induced loss of consciousness.

    Artoni, Fiorenzo / Maillard, Julien / Britz, Juliane / Seeber, Martin / Lysakowski, Christopher / Bréchet, Lucie / Tramèr, Martin R / Michel, Christoph M

    NeuroImage

    2022  Volume 256, Page(s) 119156

    Abstract: Evidence suggests that the stream of consciousness is parsed into transient brain states manifesting themselves as discrete spatiotemporal patterns of global neuronal activity. Electroencephalographical (EEG) microstates are proposed as the ... ...

    Abstract Evidence suggests that the stream of consciousness is parsed into transient brain states manifesting themselves as discrete spatiotemporal patterns of global neuronal activity. Electroencephalographical (EEG) microstates are proposed as the neurophysiological correlates of these transiently stable brain states that last for fractions of seconds. To further understand the link between EEG microstate dynamics and consciousness, we continuously recorded high-density EEG in 23 surgical patients from their awake state to unconsciousness, induced by step-wise increasing concentrations of the intravenous anesthetic propofol. Besides the conventional parameters of microstate dynamics, we introduce a new implementation of a method to estimate the complexity of microstate sequences. The brain activity under the surgical anesthesia showed a decreased sequence complexity of the stereotypical microstates, which became sparser and longer-lasting. However, we observed an initial increase in microstates' temporal dynamics and complexity with increasing depth of sedation leading to a distinctive "U-shape" that may be linked to the paradoxical excitation induced by moderate levels of propofol. Our results support the idea that the brain is in a metastable state under normal conditions, balancing between order and chaos in order to flexibly switch from one state to another. The temporal dynamics of EEG microstates indicate changes of this critical balance between stability and transition that lead to altered states of consciousness.
    MeSH term(s) Brain/physiology ; Consciousness/physiology ; Electroencephalography/methods ; Humans ; Propofol/pharmacology ; Unconsciousness/chemically induced
    Chemical Substances Propofol (YI7VU623SF)
    Language English
    Publishing date 2022-03-29
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1147767-2
    ISSN 1095-9572 ; 1053-8119
    ISSN (online) 1095-9572
    ISSN 1053-8119
    DOI 10.1016/j.neuroimage.2022.119156
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  3. Article: Microsynt

    Artoni, Fiorenzo / Maillard, Julien / Britz, Juliane / Brunet, Denis / Lysakowski, Christopher / Tramèr, Martin R. / Michel, Christoph M.

    NeuroImage

    Exploring the syntax of EEG microstates

    2023  

    Abstract: ... to be attracted towards "A - B - C " microstate hubs, and most prominently A - B binary loops ... Conversely, with full unconsciousness, sequences of microstates are attracted towards "C - D - E " hubs, and ... most prominently C - E binary loops, confirming the putative relation of microstates A and B ...

    Title translation Microsynt: Erforschung der Syntax von EEG-Mikrozuständen (DeepL)
    Abstract Microstates represent electroencephalographic (EEG) activity as a sequence of switching, transient, metastable states. Growing evidence suggests the useful information on brain states is to be found in the higher-order temporal structure of these sequences. Instead of focusing on transition probabilities, here we propose "Microsynt", a method designed to highlight higher-order interactions that form a preliminary step towards understanding the syntax of microstate sequences of any length and complexity. Microsynt extracts an optimal vocabulary of "words " based on the length and complexity of the full sequence of microstates. Words are then sorted into classes of entropy and their representativeness within each class is statistically compared with surrogate and theoretical vocabularies. We applied the method on EEG data previously collected from healthy subjects undergoing propofol anesthesia, and compared their "fully awake " (BASE) and "fully unconscious " (DEEP) conditions. Results show that microstate sequences, even at rest, are not random but tend to behave in a more predictable way, favoring simpler sub-sequences, or "words ". Contrary to high-entropy words, lowest-entropy binary microstate loops are prominent and favored on average 10 times more than what is theoretically expected. Progressing from BASE to DEEP, the representation of low-entropy words increases while that of high-entropy words decreases. During the awake state, sequences of microstates tend to be attracted towards "A - B - C " microstate hubs, and most prominently A - B binary loops. Conversely, with full unconsciousness, sequences of microstates are attracted towards "C - D - E " hubs, and most prominently C - E binary loops, confirming the putative relation of microstates A and B to externally-oriented cognitive processes and microstate C and E to internally-generated mental activity. Microsynt can form a syntactic signature of microstate sequences that can be used to reliably differentiate two or more conditions.
    Keywords Betäubung durch Suchtmittel ; Bewusstseinszustände ; Consciousness States ; Electrical Activity ; Electroencephalography ; Elektrische Aktivität ; Elektroenzephalographie ; Narcosis
    Language English
    Document type Article
    ZDB-ID 1147767-2
    ISSN 1095-9572 ; 1053-8119
    ISSN (online) 1095-9572
    ISSN 1053-8119
    DOI 10.1016/j.neuroimage.2023.120196
    Database PSYNDEX

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  4. Article ; Online: Pediatric kidney transplantation: outcomes with under and over 6-year-old donors.

    Lysakowski, Simone / Druck Garcia, Clotilde / Weisheimer Rohde, Roberta / Pascual Vitola, Santo / Silva Pires, Fabian / Carla de Souza, Vandrea / Enrico Ventura, Pedro / Kist, Roger

    Jornal de pediatria

    2023  Volume 100, Issue 1, Page(s) 67–73

    Abstract: Objective: Kidney shortage for pediatric kidney transplantation (PKT) entails the need to use low-weight and age donors, despite the apprehension. The aim of this study was to analyze the pediatric deceased donor kidney transplantations (pDDKT) outcomes ...

    Abstract Objective: Kidney shortage for pediatric kidney transplantation (PKT) entails the need to use low-weight and age donors, despite the apprehension. The aim of this study was to analyze the pediatric deceased donor kidney transplantations (pDDKT) outcomes in the first year after the procedure, stratified by donor age.
    Method: Retrospective cohort of pDDKTs carried out between January 2013, and January 2018, at a PKT reference hospital in Southern Brazil. Donors were divided into group 1 (≤ 6 years), and group 2 (> 6 years); the analysis of the outcomes was carried out in the same period.
    Results: There were 143 pDDKTs; 51 (35.66%) in group 1; and 92 (64.34%) in group 2. In both groups there were 17 graft losses (11.8%), with vascular thrombosis as the main cause (group 1: 5; group 2: 4). Among the complications, renal artery stenosis (RAS) with indication for angioplasty and stenting was more frequent in group 1 (7.8%; group 2: 2.2%). The 1-year Renal Transplant Recipients' and graft survival did not show significant differences between the groups, (p =  = 0.95). However, the Glomerular Filtration Rate analysis was higher in group 2, reaching, in the 12th month, 79.3 mL/min/1,73m2, compared to 69.7 mL/min/1,73m
    Conclusions: Small donors can be considered for pDDKTs, as long as there is an expert team to perform the transplantation.
    MeSH term(s) Humans ; Child ; Kidney Transplantation ; Retrospective Studies ; Graft Rejection/etiology ; Tissue Donors ; Kidney ; Graft Survival ; Treatment Outcome
    Language English
    Publishing date 2023-08-14
    Publishing country Brazil
    Document type Journal Article
    ZDB-ID 731324-x
    ISSN 1678-4782 ; 0021-7557
    ISSN (online) 1678-4782
    ISSN 0021-7557
    DOI 10.1016/j.jped.2023.07.005
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  5. Article ; Online: Language Monitoring in Brain Surgery Under General Anesthesia.

    Martin, Jennifer / Tyrand, Rémi / Lopez, Ursula / Bernasconi Pertusio, Françoise / Lysakowski, Christopher / Laganaro, Marina / Schaller, Karl / Boëx, Colette

    Journal of neurosurgical anesthesiology

    2020  Volume 32, Issue 3, Page(s) 268–272

    Abstract: Background: Awake surgeries for cerebral lesion resection have several limitations including patient fear, discomfort, or pain. This study aimed to determine whether components of language function could be measured under general anesthesia. In this ... ...

    Abstract Background: Awake surgeries for cerebral lesion resection have several limitations including patient fear, discomfort, or pain. This study aimed to determine whether components of language function could be measured under general anesthesia. In this study, the occurrence of mismatch negativity (MMN) was searched in evoked potentials for phonological sounds.
    Materials and methods: Five normal hearing, French native speaker, awake volunteers participated in evaluating the phonological task (4 females and 1 male). Eleven normal-hearing, French native speaker patients (6 left and 5 right hemisphere lesions) participated at the time of their tumor neurosurgery (3 females and 8 males). Repetitions of the standard syllable /pa/ with the insertion of 1 deviant /po/ were presented through earphones. The difference between averaged epochs of standards and deviants syllables determined the MMN. During surgery, total intravenous anesthesia was performed with propofol and synthetic opioid sufentanil. The bispectral index was targeted (40 to 60).
    Results: The MMN was found in all awake volunteers and validated by an N250 component. In the patient group, the electroencephalogram analysis was not possible in 4 of 11 patients because of anesthesia being too deep, burst suppression, or a high level of noise (>40 μV). Significant N250 response was obtained in 5 of 7 (71.4%) patients under general anesthesia. The 2 other patients also showed MMN which did not reach significance.
    Conclusions: To our knowledge, this is the first demonstration that phonological processing can be measured during brain surgery under general anesthesia, suggesting that some language processing persists under the condition of unconsciousness. These results encourage further study of language processing under general anesthesia with the goal of making intraoperative neuromonitoring.
    MeSH term(s) Anesthesia, General/methods ; Brain/physiology ; Brain/surgery ; Brain Neoplasms/surgery ; Electroencephalography/methods ; Evoked Potentials/physiology ; Female ; France ; Humans ; Language ; Male ; Middle Aged ; Phonetics
    Language English
    Publishing date 2020-01-13
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1018119-2
    ISSN 1537-1921 ; 0898-4921
    ISSN (online) 1537-1921
    ISSN 0898-4921
    DOI 10.1097/ANA.0000000000000602
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  6. Article ; Online: Effect of sufentanil on bispectral index in the elderly.

    de Valence, T / Elia, N / Czarnetzki, C / Dumont, L / Tramèr, M R / Lysakowski, C

    Anaesthesia

    2017  Volume 73, Issue 2, Page(s) 216–222

    Abstract: We examined the impact of adding sufentanil during anaesthesia induction with propofol on bispectral index values in elderly patients (≥ 65 years). Patients were randomly assigned to receive a target-controlled sufentanil infusion (effect-site ... ...

    Abstract We examined the impact of adding sufentanil during anaesthesia induction with propofol on bispectral index values in elderly patients (≥ 65 years). Patients were randomly assigned to receive a target-controlled sufentanil infusion (effect-site concentration of 0.3 ng.ml
    MeSH term(s) Aged ; Aged, 80 and over ; Anesthesia, Intravenous/methods ; Anesthetics, Intravenous ; Consciousness Monitors ; Double-Blind Method ; Female ; Humans ; Male ; Propofol ; Sex Characteristics ; Sufentanil ; Unconsciousness
    Chemical Substances Anesthetics, Intravenous ; Sufentanil (AFE2YW0IIZ) ; Propofol (YI7VU623SF)
    Language English
    Publishing date 2017-11-03
    Publishing country England
    Document type Journal Article ; Randomized Controlled Trial
    ZDB-ID 80033-8
    ISSN 1365-2044 ; 0003-2409
    ISSN (online) 1365-2044
    ISSN 0003-2409
    DOI 10.1111/anae.14102
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  7. Article ; Online: Transcranial Doppler in the Diagnosis of Cerebral Vasospasm: An Updated Meta-Analysis.

    Mastantuono, Jean-Mathieu / Combescure, Christophe / Elia, Nadia / Tramèr, Martin R / Lysakowski, Christopher

    Critical care medicine

    2018  Volume 46, Issue 10, Page(s) 1665–1672

    Abstract: Objectives: To evaluate the performance of transcranial Doppler and transcranial color-coded duplex Doppler in patients with cerebral vasospasm due to aneurysm rupture. Angiography was considered as the gold standard comparator.: Data sources: Search ...

    Abstract Objectives: To evaluate the performance of transcranial Doppler and transcranial color-coded duplex Doppler in patients with cerebral vasospasm due to aneurysm rupture. Angiography was considered as the gold standard comparator.
    Data sources: Search in MEDLINE, Embase, and Central from January 2001 to October 2017, without language restriction. Bibliographies of retrieved articles were screened for additional studies.
    Study selection: Randomized studies comparing transcranial Doppler or transcranial color-coded duplex Doppler with angiography in adults.
    Data extraction: Data were extracted independently by several investigators. Sensitivity and specificity were combined across studies using a bivariate model. Preferred Reporting Items for Systematic Reviews and Meta-Analyses was used for reporting and Quality Assessment of Diagnostic Accuracy Studies-2 for quality assessment.
    Data synthesis: We included 18 studies. Fifteen tested transcranial Doppler. For the middle cerebral artery (10 studies, 1,408 tests), the pooled sensitivity was 66.7% (95% CI, 55.9-75.9) and specificity was 89.5% (80.3-94.7). Three studies (278 tests) tested transcranial color-coded duplex Doppler for the middle cerebral artery. The pooled sensitivity was 81.5% (66.0-90.0), and specificity was 96.6% (93.0-98.0). For an arbitrarily chosen prevalence of vasospasm of 70%, positive and negative predictive values were 93.7% (88.9-96.6) and 53.4% (46.7-60.9) for transcranial Doppler and 98.2% (96.4-99.1) and 69.1% (56.1-80.9) for transcranial color-coded duplex Doppler.
    Conclusions: Assuming a high prevalence of vasospasm of the middle cerebral artery, both transcranial Doppler and transcranial color-coded duplex Doppler are likely to detect it, but neither is useful to exclude it. There is no convincing evidence that the accuracy of transcranial color-coded duplex Doppler is any better than that of transcranial Doppler. For arteries other than middle cerebral artery, there is a lack of evidence of the usefulness of transcranial Doppler.
    MeSH term(s) Blood Flow Velocity ; Female ; Humans ; Infarction, Middle Cerebral Artery/diagnostic imaging ; Male ; Middle Cerebral Artery/diagnostic imaging ; Ultrasonography, Doppler, Color/methods ; Ultrasonography, Doppler, Transcranial/methods ; Vasoconstriction ; Vasospasm, Intracranial/diagnostic imaging
    Language English
    Publishing date 2018-08-02
    Publishing country United States
    Document type Journal Article ; Meta-Analysis
    ZDB-ID 197890-1
    ISSN 1530-0293 ; 0090-3493
    ISSN (online) 1530-0293
    ISSN 0090-3493
    DOI 10.1097/CCM.0000000000003297
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  8. Article ; Online: Stability, compatibility and microbiological activity studies of meropenem-clavulanate potassium.

    Cielecka-Piontek, Judyta / Szymanowska-Powałowska, Daria / Paczkowska, Magdalena / Łysakowski, Piotr / Zalewski, Przemysław / Garbacki, Piotr

    The Journal of antibiotics

    2014  Volume 68, Issue 1, Page(s) 35–39

    Abstract: ... 0.9% NaCl and 5% glucose at room temperature and at 5 °C. The degradation rates of MEM ...

    Abstract Meropenem (MEM) and clavulanate potassium have been reported to demonstrate highly effective activity against Mycobacterium tuberculosis. There have been no reports on research into the complex of these chemotherapeutics concerning their mutually dependent stability or microbiological action on other microorganisms. Stability and compatibility studies of MEM/clavulanate potassium were conducted by using an HPLC-DAD method. The antibacterial activity of MEM/clavulanate potassium was tested in vitro against a selection of indicator bacteria strains by determining the MIC as well as analyzing the kinetics of changes in the concentrations of Pseudomonas aeruginosa, Staphylococcus aureus and Listeria monocytogenes caused by the action of MEM/clavulanate potassium. The stability and compatibility of MEM/clavulanate potassium were examined in aqua pro iniectione, 0.9% NaCl and 5% glucose at room temperature and at 5 °C. The degradation rates of MEM/clavulanate potassium depended on the type of infusion solvent used. Although in aqueous solutions of MEM/clavulanate potassium neither compound showed any mutual impact on the rate of degradation, clavulanate potassium was more labile than MEM. The synergy between these two resulted in a significantly lower value of MIC as compared to the values observed for the individual activity of either compound. The infusion solvent in which compatibility is observed between the components of the mixture MEM/clavulanate potassium is aqua pro iniectione. The complex MEM/clavulanate potassium demonstrates synergic antibacterial activity against P. aeruginosa, S. aureus and L. monocytogenes.
    MeSH term(s) Anti-Bacterial Agents/administration & dosage ; Anti-Bacterial Agents/chemistry ; Anti-Bacterial Agents/pharmacology ; Chromatography, High Pressure Liquid/methods ; Clavulanic Acid/administration & dosage ; Clavulanic Acid/chemistry ; Clavulanic Acid/pharmacology ; Drug Combinations ; Drug Incompatibility ; Drug Synergism ; Listeria monocytogenes/drug effects ; Meropenem ; Microbial Sensitivity Tests ; Pseudomonas aeruginosa/drug effects ; Solvents/chemistry ; Staphylococcus aureus/drug effects ; Temperature ; Thienamycins/administration & dosage ; Thienamycins/chemistry ; Thienamycins/pharmacology
    Chemical Substances Anti-Bacterial Agents ; Drug Combinations ; Solvents ; Thienamycins ; Clavulanic Acid (23521W1S24) ; Meropenem (FV9J3JU8B1)
    Language English
    Publishing date 2014-07-30
    Publishing country Japan
    Document type Journal Article
    ZDB-ID 390800-8
    ISSN 1881-1469 ; 0021-8820 ; 0368-3532
    ISSN (online) 1881-1469
    ISSN 0021-8820 ; 0368-3532
    DOI 10.1038/ja.2014.92
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  9. Article ; Online: Altered Outer Hair Cell Mitochondrial and Subsurface Cisternae Connectomics Are Candidate Mechanisms for Hearing Loss in Mice.

    Perkins, Guy / Lee, Jeong Han / Park, Seojin / Kang, Mincheol / Perez-Flores, Maria C / Ju, Saeyeon / Phillips, Grady / Lysakowski, Anna / Gratton, Michael Anne / Yamoah, Ebenezer N

    The Journal of neuroscience : the official journal of the Society for Neuroscience

    2020  Volume 40, Issue 44, Page(s) 8556–8572

    Abstract: Organelle crosstalk is vital for cellular functions. The propinquity of mitochondria, ER, and plasma membrane promote regulation of multiple functions, which include intracellular ... ...

    Abstract Organelle crosstalk is vital for cellular functions. The propinquity of mitochondria, ER, and plasma membrane promote regulation of multiple functions, which include intracellular Ca
    MeSH term(s) Adenosine Triphosphate/biosynthesis ; Aging/physiology ; Animals ; Calcium/metabolism ; Connectome ; Cytoplasm/metabolism ; Endoplasmic Reticulum/pathology ; Energy Metabolism/physiology ; Evoked Potentials, Auditory, Brain Stem/physiology ; Female ; Hair Cells, Auditory, Outer/pathology ; Hearing Loss/pathology ; Male ; Membrane Potential, Mitochondrial/physiology ; Mice ; Mitochondria/pathology ; Neuronal Plasticity/drug effects ; Potassium/pharmacology
    Chemical Substances Adenosine Triphosphate (8L70Q75FXE) ; Potassium (RWP5GA015D) ; Calcium (SY7Q814VUP)
    Language English
    Publishing date 2020-10-05
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 604637-x
    ISSN 1529-2401 ; 0270-6474
    ISSN (online) 1529-2401
    ISSN 0270-6474
    DOI 10.1523/JNEUROSCI.2901-19.2020
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  10. Article ; Online: In reply.

    Hovaguimian, Frédérique / Lysakowski, Christopher / Elia, Nadia / Tramèr, Martin R

    Anesthesiology

    2014  Volume 120, Issue 4, Page(s) 1053–1054

    MeSH term(s) Humans ; Lung/physiology ; Oxygen/therapeutic use ; Oxygen Inhalation Therapy/methods ; Postoperative Nausea and Vomiting/prevention & control ; Surgical Wound Infection/prevention & control
    Chemical Substances Oxygen (S88TT14065)
    Language English
    Publishing date 2014-04
    Publishing country United States
    Document type Comment ; Editorial
    ZDB-ID 269-0
    ISSN 1528-1175 ; 0003-3022
    ISSN (online) 1528-1175
    ISSN 0003-3022
    DOI 10.1097/ALN.0000000000000158
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