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  1. Article ; Online: Interplay between brain oxygenation and the development of hypothermia in endotoxic shock.

    Moretti, Eduardo H / Lino, Caroline A / Steiner, Alexandre A

    Shock (Augusta, Ga.)

    2024  

    Abstract: Abstract: There is evidence to suggest that the hypothermia observed in the most severe cases of systemic inflammation or sepsis is a regulated response with potential adaptive value, but the mechanisms involved are poorly understood. Here, we ... ...

    Abstract Abstract: There is evidence to suggest that the hypothermia observed in the most severe cases of systemic inflammation or sepsis is a regulated response with potential adaptive value, but the mechanisms involved are poorly understood. Here, we investigated the interplay between brain oxygenation (assessed by tissue PO2) and the development of hypothermia in unanesthetized rats challenged with a hypotension-inducing dose of bacterial lipopolysaccharide (LPS, 1 mg/kg i.v.). At an ambient temperature of 22 °C, oxygen consumption (V̇O2) began to fall only a few minutes after the LPS injection, and this suppression in metabolic rate preceded the decrease in core temperature. No reduction in brain PO2 was observed prior to the development of the hypometabolic, hypothermic response, ruling out the possibility that brain hypoxia served as a trigger for hypothermia in this model. Brain PO2 was even increased. Such an improvement in brain oxygenation could reflect either an increased O2 delivery or a decreased O2 consumption. The former explanation seems unlikely because blood flow (cardiac output) was being progressively decreased during the recording period. On the other hand, the decrease in V̇O2 usually preceded the rise in PO2, and an inverse correlation between V̇O2 and brain PO2 was consistently observed. These findings do not support the existence of a closed-loop feedback relationship between brain oxygenation and hypothermia in systemic inflammation. The data are consistent with a feedforward mechanism in which hypothermia is triggered (possibly by cryogenic inflammatory mediators) in anticipation of changes in brain oxygenation to prevent the development of tissue hypoxia.
    Language English
    Publishing date 2024-03-25
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1185432-7
    ISSN 1540-0514 ; 1073-2322
    ISSN (online) 1540-0514
    ISSN 1073-2322
    DOI 10.1097/SHK.0000000000002350
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Should we let fever run its course in the early stages of COVID-19?

    Steiner, Alexandre A

    Journal of the Royal Society of Medicine

    2020  Volume 113, Issue 10, Page(s) 407–409

    MeSH term(s) Adaptation, Physiological/drug effects ; Adaptation, Physiological/immunology ; Anthropology, Medical ; Antipyretics/administration & dosage ; Antipyretics/adverse effects ; Betacoronavirus/isolation & purification ; COVID-19 ; Coronavirus Infections/diagnosis ; Coronavirus Infections/immunology ; Coronavirus Infections/physiopathology ; Culture ; Diagnostic Errors/adverse effects ; Diagnostic Errors/prevention & control ; Disease Progression ; Drug Misuse/adverse effects ; Drug Misuse/prevention & control ; Fever/drug therapy ; Fever/etiology ; Fever/psychology ; Humans ; Immunity/physiology ; Pandemics ; Pneumonia, Viral/diagnosis ; Pneumonia, Viral/immunology ; Pneumonia, Viral/physiopathology ; SARS-CoV-2
    Chemical Substances Antipyretics
    Keywords covid19
    Language English
    Publishing date 2020-09-15
    Publishing country England
    Document type Journal Article
    ZDB-ID 6731-3
    ISSN 1758-1095 ; 0141-0768 ; 0035-9157
    ISSN (online) 1758-1095
    ISSN 0141-0768 ; 0035-9157
    DOI 10.1177/0141076820951544
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Should we let fever run its course in the early stages of COVID-19?

    Steiner, Alexandre A

    Journal of the Royal Society of Medicine

    2020  Volume 113, Issue 10, Page(s) 407–409

    Keywords General Medicine ; covid19
    Language English
    Publisher SAGE Publications
    Publishing country us
    Document type Article ; Online
    ZDB-ID 6731-3
    ISSN 1758-1095 ; 0141-0768 ; 0035-9157
    ISSN (online) 1758-1095
    ISSN 0141-0768 ; 0035-9157
    DOI 10.1177/0141076820951544
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article: The dynamic nature of resting metabolic rate.

    Steiner, Alexandre A

    Temperature (Austin, Tex.)

    2017  Volume 4, Issue 3, Page(s) 206–207

    Language English
    Publishing date 2017-08-04
    Publishing country United States
    Document type Editorial
    ISSN 2332-8940
    ISSN 2332-8940
    DOI 10.1080/23328940.2017.1356426
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Energy Trade-offs in Host Defense: Immunology Meets Physiology.

    Steiner, Alexandre A / Romanovsky, Andrej A

    Trends in endocrinology and metabolism: TEM

    2019  Volume 30, Issue 12, Page(s) 875–878

    Abstract: Host defense relies not only on microbicidal mechanisms (resistance), but also on management of collateral damage (tolerance). Here, we discuss how this immunology concept converges with a physiology-born theory on the dichotomy of thermometabolic ... ...

    Abstract Host defense relies not only on microbicidal mechanisms (resistance), but also on management of collateral damage (tolerance). Here, we discuss how this immunology concept converges with a physiology-born theory on the dichotomy of thermometabolic responses in infection (fever versus hypothermia), yielding a model of immunity that transcends discipline barriers.
    MeSH term(s) Animals ; Fever/immunology ; Fever/metabolism ; Fever/physiopathology ; Humans ; Hypothermia/immunology ; Hypothermia/metabolism ; Hypothermia/physiopathology ; Immunity/physiology ; Inflammation/immunology ; Inflammation/metabolism ; Inflammation/physiopathology
    Language English
    Publishing date 2019-10-25
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 1042384-9
    ISSN 1879-3061 ; 1043-2760
    ISSN (online) 1879-3061
    ISSN 1043-2760
    DOI 10.1016/j.tem.2019.08.012
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Reduced oxygen utilization in septic shock: disorder or adaptation?

    Steiner, Alexandre A

    Temperature (Austin, Tex.)

    2015  Volume 2, Issue 4, Page(s) 447–448

    Abstract: A fall in oxygen utilization during septic or endotoxic shock is thought to reflect circulatory hypoxia or mitochondrial dysfunction, but these pathology-oriented hypotheses do not explain all clinical observations. Here we discuss an alternative ... ...

    Abstract A fall in oxygen utilization during septic or endotoxic shock is thought to reflect circulatory hypoxia or mitochondrial dysfunction, but these pathology-oriented hypotheses do not explain all clinical observations. Here we discuss an alternative hypothesis of how oxygen utilization could fall as the result of a physiological thermometabolic adaptation.
    Language English
    Publishing date 2015-02-05
    Publishing country United States
    Document type Journal Article
    ISSN 2332-8940
    ISSN 2332-8940
    DOI 10.1080/23328940.2014.996484
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Diet-induced obesity attenuates the hypothermic response to lipopolysaccharide independently of TNF-α production.

    Komegae, Evilin N / Fonseca, Monique T / Steiner, Alexandre A

    Temperature (Austin, Tex.)

    2020  Volume 7, Issue 3, Page(s) 270–276

    Abstract: Life-threatening infections (sepsis) are usually associated with co-morbidities, among which obesity deserves attention. Here, we evaluated whether and how obesity affects the switch from fever to hypothermia that occurs in the most severe cases of ... ...

    Abstract Life-threatening infections (sepsis) are usually associated with co-morbidities, among which obesity deserves attention. Here, we evaluated whether and how obesity affects the switch from fever to hypothermia that occurs in the most severe cases of sepsis, which is thought to provide physiological support for a change in host defense strategy from resistance to tolerance. Obesity was induced by keeping rats on a high-fat diet for 32-34 weeks. The hypothermia induced by a high dose of bacterial lipopolysaccharide (LPS, 300 μg/animal, i.a.) was attenuated in the obese rats, as compared to their low-fat diet counterparts. Surprisingly, such attenuation occurred in spite of an enhancement in the circulating level of TNF-α, the most renowned mediator of LPS-induced hypothermia. Hence, it seems that factors counteracting not the production, but rather the action of TNF-α are at play in rats with diet-induced obesity. One of these factors might be IL-1β, a febrigenic mediator that also had its circulating levels augmented in the obese rats challenged with LPS. Taken together with previous reports of diet-induced obesity enhancing the fever induced by lower doses of LPS, the results of the present study indicate that obesity biases host defense toward a fever/resistance strategy,
    Language English
    Publishing date 2020-01-09
    Publishing country United States
    Document type Journal Article
    ISSN 2332-8940
    ISSN 2332-8940
    DOI 10.1080/23328940.2019.1707155
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Neural signatures of indirect pathway activity during subthalamic stimulation in Parkinson's disease.

    Steiner, Leon A / Crompton, David / Sumarac, Srdjan / Vetkas, Artur / Germann, Jürgen / Scherer, Maximilian / Justich, Maria / Boutet, Alexandre / Popovic, Milos R / Hodaie, Mojgan / Kalia, Suneil K / Fasano, Alfonso / Hutchison Wd, William D / Lozano, Andres M / Lankarany, Milad / Kühn, Andrea A / Milosevic, Luka

    Nature communications

    2024  Volume 15, Issue 1, Page(s) 3130

    Abstract: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) produces an electrophysiological signature called evoked resonant neural activity (ERNA); a high-frequency oscillation that has been linked to treatment efficacy. However, the single-neuron ... ...

    Abstract Deep brain stimulation (DBS) of the subthalamic nucleus (STN) produces an electrophysiological signature called evoked resonant neural activity (ERNA); a high-frequency oscillation that has been linked to treatment efficacy. However, the single-neuron and synaptic bases of ERNA are unsubstantiated. This study proposes that ERNA is a subcortical neuronal circuit signature of DBS-mediated engagement of the basal ganglia indirect pathway network. In people with Parkinson's disease, we: (i) showed that each peak of the ERNA waveform is associated with temporally-locked neuronal inhibition in the STN; (ii) characterized the temporal dynamics of ERNA; (iii) identified a putative mesocircuit architecture, embedded with empirically-derived synaptic dynamics, that is necessary for the emergence of ERNA in silico; (iv) localized ERNA to the dorsal STN in electrophysiological and normative anatomical space; (v) used patient-wise hotspot locations to assess spatial relevance of ERNA with respect to DBS outcome; and (vi) characterized the local fiber activation profile associated with the derived group-level ERNA hotspot.
    MeSH term(s) Humans ; Parkinson Disease/therapy ; Deep Brain Stimulation/methods ; Subthalamic Nucleus/physiology ; Basal Ganglia/physiology ; Neurons/physiology
    Language English
    Publishing date 2024-04-11
    Publishing country England
    Document type Journal Article
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-024-47552-6
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Insect Antiadhesive Surfaces Using Electrosprayed Wrinkled Ethyl Cellulose Particles.

    Bergmann, Johannes B / Redondo, Alexandre / Steiner, Ullrich / Wilts, Bodo D / Moatsou, Dafni

    ACS applied materials & interfaces

    2021  Volume 13, Issue 7, Page(s) 9232–9238

    Abstract: A range of plants developed leaves, the surfaces of which prevent or diminish insect adhesion due to their microscopic topography. Well known examples include the leaves of the lychee tree ( ...

    Abstract A range of plants developed leaves, the surfaces of which prevent or diminish insect adhesion due to their microscopic topography. Well known examples include the leaves of the lychee tree (
    MeSH term(s) Adhesiveness/drug effects ; Animals ; Cellulose/analogs & derivatives ; Cellulose/chemistry ; Cellulose/pharmacology ; Coleoptera ; Litchi/chemistry ; Particle Size ; Plant Leaves/chemistry ; Surface Properties ; Viscosity
    Chemical Substances ethyl cellulose (7Z8S9VYZ4B) ; Cellulose (9004-34-6)
    Language English
    Publishing date 2021-02-11
    Publishing country United States
    Document type Journal Article
    ISSN 1944-8252
    ISSN (online) 1944-8252
    DOI 10.1021/acsami.0c21602
    Database MEDical Literature Analysis and Retrieval System OnLINE

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