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  1. Article: Homogenized finite element analysis of distal tibia sections: Achievements and limitations.

    Simon, Mathieu / Indermaur, Michael / Schenk, Denis / Voumard, Benjamin / Zderic, Ivan / Mischler, Dominic / Pretterklieber, Michael / Zysset, Philippe

    Bone reports

    2024  Volume 21, Page(s) 101752

    Abstract: High-resolution peripheral quantitative computed tomography (HR-pQCT) based micro-finite element (μFE) analysis allows accurate prediction of stiffness and ultimate load of standardised (∼1 cm) distal radius and tibia sections. An alternative homogenized ...

    Abstract High-resolution peripheral quantitative computed tomography (HR-pQCT) based micro-finite element (μFE) analysis allows accurate prediction of stiffness and ultimate load of standardised (∼1 cm) distal radius and tibia sections. An alternative homogenized finite element method (hFE) was recently validated to compute the ultimate load of larger (∼2 cm) distal radius sections that include Colles' fracture sites. Since the mechanical integrity of the weight-bearing distal tibia is gaining clinical interest, it has been shown that the same properties can be used to predict the strength of both distal segments of the radius and the tibia. Despite the capacity of hFE to predict structural properties of distal segments of the radius and the tibia, the limitations of such homogenization scheme remain unclear. Therefore, the objective of this study is to build a complete mechanical data set of the compressive behavior of distal segments of the tibia and to compare quantitatively the structural properties with the hFE predictions. As a further aim, it is intended to verify whether hFE is also able to capture the post-yield strain localisation or fracture zones in such a bone section, despite the absence of strain softening in the constitutive model. Twenty-five fresh-frozen distal parts of tibias of human donors were used in this study. Sections were cut corresponding to an in-house triple-stack protocol HR-pQCT scan, lapped, and scanned using micro computed tomography (μCT). The sections were tested in compression until failure, unloaded and scanned again in μCT. Volumetric bone mineral density (vBMD) and bone mineral content (BMC) were correlated to compression test results. hFE analysis was performed in order to compare computational predictions (stiffness, yield load and plastic deformation field pattern) with the compressive experiment. Namely, strain localization was assessed based on digital volume correlation (DVC) results and qualitatively compared to hFE predictions by comparing mid-slices patterns. Bone mineral content (BMC) showed a good correlation with stiffness (R
    Language English
    Publishing date 2024-03-26
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2821774-3
    ISSN 2352-1872
    ISSN 2352-1872
    DOI 10.1016/j.bonr.2024.101752
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Analgesic Medication Use During Exercise-Based Rehabilitation in Individuals With Low Back Pain: A Call to Action.

    Shahidi, Bahar / Schenk, Simon / Raiszadeh, Kamshad

    Physical therapy

    2021  Volume 101, Issue 3

    MeSH term(s) Analgesics/therapeutic use ; Exercise Therapy/methods ; Humans ; Low Back Pain/drug therapy ; Low Back Pain/rehabilitation
    Chemical Substances Analgesics
    Language English
    Publishing date 2021-01-14
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 415886-6
    ISSN 1538-6724 ; 0031-9023
    ISSN (online) 1538-6724
    ISSN 0031-9023
    DOI 10.1093/ptj/pzab011
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Comparing the Colloidal Stabilities of Commercial and Biogenic Iron Oxide Nanoparticles That Have Potential In Vitro/In Vivo Applications.

    Schwan, Jonas / Markert, Simon / Rosenfeldt, Sabine / Schüler, Dirk / Mickoleit, Frank / Schenk, Anna S

    Molecules (Basel, Switzerland)

    2023  Volume 28, Issue 13

    Abstract: For the potential in vitro/in vivo applications of magnetic iron oxide nanoparticles, their stability in different physiological fluids has to be ensured. This important prerequisite includes the preservation of the particles' stability during the ... ...

    Abstract For the potential in vitro/in vivo applications of magnetic iron oxide nanoparticles, their stability in different physiological fluids has to be ensured. This important prerequisite includes the preservation of the particles' stability during the envisaged application and, consequently, their invariance with respect to the transfer from storage conditions to cell culture media or even bodily fluids. Here, we investigate the colloidal stabilities of commercial nanoparticles with different coatings as a model system for biogenic iron oxide nanoparticles (magnetosomes) isolated from magnetotactic bacteria. We demonstrate that the stability can be evaluated and quantified by determining the intensity-weighted average of the particle sizes (
    MeSH term(s) Magnetosomes/metabolism ; Nanoparticles ; Magnetic Iron Oxide Nanoparticles
    Language English
    Publishing date 2023-06-21
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 1413402-0
    ISSN 1420-3049 ; 1431-5165 ; 1420-3049
    ISSN (online) 1420-3049
    ISSN 1431-5165 ; 1420-3049
    DOI 10.3390/molecules28134895
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Functional Abdominal Pain Disorders in Children May Be Associated with Food Intolerance/Malabsorption.

    Schnedl, Wolfgang J / Schenk, Michael / Michaelis, Simon / Enko, Dietmar / Mangge, Harald

    Children (Basel, Switzerland)

    2023  Volume 10, Issue 9

    Abstract: Functional abdominal pain disorders (FAPDs) are among the most common types of chronic pain disorders in children. FAPD symptoms are characterized by chronic abdominal pain and changed bowel movements. The pathophysiology of FAPDs in children is unknown, ...

    Abstract Functional abdominal pain disorders (FAPDs) are among the most common types of chronic pain disorders in children. FAPD symptoms are characterized by chronic abdominal pain and changed bowel movements. The pathophysiology of FAPDs in children is unknown, but these conditions may have an imprecise clinical overlap to food intolerance/malabsorption. We report on 51 consecutive children (23/28 males/females; median age 15.3 years) with investigated FAPDs from 2017 to 2022 in this retrospective pilot study. Small intestinal biopsies in children demonstrated the association of lactase and diamine oxidase (DAO), which prompted us to perform hydrogen (H
    Language English
    Publishing date 2023-08-24
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2732685-8
    ISSN 2227-9067
    ISSN 2227-9067
    DOI 10.3390/children10091444
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Unravelling the amorphous structure and crystallization mechanism of GeTe phase change memory materials.

    Wintersteller, Simon / Yarema, Olesya / Kumaar, Dhananjeya / Schenk, Florian M / Safonova, Olga V / Abdala, Paula M / Wood, Vanessa / Yarema, Maksym

    Nature communications

    2024  Volume 15, Issue 1, Page(s) 1011

    Abstract: The reversible phase transitions in phase-change memory devices can switch on the order of nanoseconds, suggesting a close structural resemblance between the amorphous and crystalline phases. Despite this, the link between crystalline and amorphous ... ...

    Abstract The reversible phase transitions in phase-change memory devices can switch on the order of nanoseconds, suggesting a close structural resemblance between the amorphous and crystalline phases. Despite this, the link between crystalline and amorphous tellurides is not fully understood nor quantified. Here we use in-situ high-temperature x-ray absorption spectroscopy (XAS) and theoretical calculations to quantify the amorphous structure of bulk and nanoscale GeTe. Based on XAS experiments, we develop a theoretical model of the amorphous GeTe structure, consisting of a disordered fcc-type Te sublattice and randomly arranged chains of Ge atoms in a tetrahedral coordination. Strikingly, our intuitive and scalable model provides an accurate description of the structural dynamics in phase-change memory materials, observed experimentally. Specifically, we present a detailed crystallization mechanism through the formation of an intermediate, partially stable 'ideal glass' state and demonstrate differences between bulk and nanoscale GeTe leading to size-dependent crystallization temperature.
    Language English
    Publishing date 2024-02-03
    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/s41467-024-45327-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Insights into post-translational regulation of skeletal muscle contractile function by the acetyltransferases, p300 and CBP.

    Meyer, Gretchen A / Ferey, Jeremie L A / Sanford, James A / Fitzgerald, Liam S / Greenberg, Akiva E / Svensson, Kristoffer / Greenberg, Michael J / Schenk, Simon

    bioRxiv : the preprint server for biology

    2024  

    Abstract: Mice with skeletal muscle-specific inducible double knockout of the lysine acetyltransferases, p300 (E1A binding protein p300) and CBP (cAMP-response element-binding protein binding protein), referred to as i-mPCKO, demonstrate a dramatic loss of ... ...

    Abstract Mice with skeletal muscle-specific inducible double knockout of the lysine acetyltransferases, p300 (E1A binding protein p300) and CBP (cAMP-response element-binding protein binding protein), referred to as i-mPCKO, demonstrate a dramatic loss of contractile function in skeletal muscle and ultimately die within 7 days. Given that many proteins involved in ATP generation and cross-bridge cycling are acetylated, we investigated whether these processes are dysregulated in skeletal muscle from i-mPCKO mice and thus could underlie the rapid loss of muscle contractile function. Just 4-5 days after inducing knockout of p300 and CBP in skeletal muscle from adult i-mPCKO mice, there was ∼90% reduction in
    New & noteworthy: The mechanism underlying dramatic loss of muscle contractile function with inducible deletion of both p300 and CBP in skeletal muscle remains unknown. Here we find that impairments in mitochondrial function or cross-bridge cycling are not the underlying mechanism of action. Future work will investigate other aspects of excitation-contraction coupling, such as Ca
    Language English
    Publishing date 2024-02-29
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2024.02.27.582179
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: The effect of tenotomy, neurotomy, and dual injury on mouse rotator cuff muscles: Consequences for the mouse as a preclinical model.

    Gibbons, Michael C / Silldorff, Morgan / Okuno, Hiroshi / Esparza, Mary C / Migdal, Christopher / Johnson, Seth / Schenk, Simon / Ward, Samuel R

    Journal of orthopaedic research : official publication of the Orthopaedic Research Society

    2024  Volume 42, Issue 6, Page(s) 1170–1179

    Abstract: A common animal model of muscle pathology following rotator cuff tear (RCT) is a tenotomy of the supraspinatus and infraspinatus, often combined with neurotomy of the suprascapular nerve, which induces a more robust atrophy response than tenotomy alone. ... ...

    Abstract A common animal model of muscle pathology following rotator cuff tear (RCT) is a tenotomy of the supraspinatus and infraspinatus, often combined with neurotomy of the suprascapular nerve, which induces a more robust atrophy response than tenotomy alone. However, the utility of this model depends on its similarity to human muscle pathology post-RCT, both in terms of the disease phenotype and mechanisms of muscle atrophy and fatty infiltration. Given the clinical prevalence of nerve injury is low and the muscular response to denervation is distinct from mechanical unloading in other models, an understanding of the biological influence of the nerve injury is critical for interpreting data from this RCT model. We evaluated the individual and combined effect of tenotomy and neurotomy across multiple biological scales, in a robust time-series in the mouse supraspinatus. Muscle composition, histological, and gene expression data related to muscle atrophy, degeneration-regeneration, fatty infiltration, and fibrosis were evaluated. Broadly, we found tenotomy alone caused small, transient changes in these pathological features, which resolved over the course of the study, while neurotomy alone caused a significant fatty atrophy phenotype. The dual injury group had a similar fatty atrophy phenotype to the neurotomy group, though the addition of tenotomy did marginally enhance the fat and connective tissue. Overall, these results suggest the most clinically relevant injury model, tenotomy alone, does not produce a clinically relevant phenotype. The dual injury model partially recapitulates the human condition, but it does so through a nerve injury, which is not well justified clinically.
    MeSH term(s) Animals ; Tenotomy ; Rotator Cuff Injuries/surgery ; Rotator Cuff Injuries/pathology ; Muscular Atrophy/etiology ; Disease Models, Animal ; Mice, Inbred C57BL ; Rotator Cuff/surgery ; Rotator Cuff/pathology ; Rotator Cuff/innervation ; Male ; Mice
    Language English
    Publishing date 2024-01-21
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 605542-4
    ISSN 1554-527X ; 0736-0266
    ISSN (online) 1554-527X
    ISSN 0736-0266
    DOI 10.1002/jor.25786
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Book ; Thesis: Neurofeedback in der Behandlung des chronischen Tinnitus

    Schenk, Simone

    2005  

    Author's details Simone Schenk
    Keywords Ohrgeräusch ; Neurofeedback
    Subject EEG-Biofeedback ; EEG-Neurofeedback ; Ohrensausen ; Tinnitus aurium
    Language German
    Size VIII, 131 S. : graph. Darst., 21 cm
    Edition 1. Aufl.
    Publisher Cuvillier
    Publishing place Göttingen
    Publishing country Germany
    Document type Book ; Thesis
    Thesis / German Habilitation thesis München, Techn. Univ., Diss., 2005
    HBZ-ID HT015217399
    ISBN 3-86537-711-4 ; 978-3-86537-711-1
    Database Catalogue ZB MED Medicine, Health

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  9. Article ; Online: Comparing the Colloidal Stabilities of Commercial and Biogenic Iron Oxide Nanoparticles That Have Potential In Vitro/In Vivo Applications

    Jonas Schwan / Simon Markert / Sabine Rosenfeldt / Dirk Schüler / Frank Mickoleit / Anna S. Schenk

    Molecules, Vol 28, Iss 4895, p

    2023  Volume 4895

    Abstract: For the potential in vitro/in vivo applications of magnetic iron oxide nanoparticles, their stability in different physiological fluids has to be ensured. This important prerequisite includes the preservation of the particles’ stability during the ... ...

    Abstract For the potential in vitro/in vivo applications of magnetic iron oxide nanoparticles, their stability in different physiological fluids has to be ensured. This important prerequisite includes the preservation of the particles’ stability during the envisaged application and, consequently, their invariance with respect to the transfer from storage conditions to cell culture media or even bodily fluids. Here, we investigate the colloidal stabilities of commercial nanoparticles with different coatings as a model system for biogenic iron oxide nanoparticles (magnetosomes) isolated from magnetotactic bacteria. We demonstrate that the stability can be evaluated and quantified by determining the intensity-weighted average of the particle sizes ( Z -value) obtained from dynamic light scattering experiments as a simple quality criterion, which can also be used as an indicator for protein corona formation.
    Keywords magnetic nanoparticles ; magnetosomes ; colloidal stability ; protein corona ; Organic chemistry ; QD241-441
    Subject code 620 ; 500
    Language English
    Publishing date 2023-06-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: The Collateral Damage of the COVID-19 Outbreak on Mental Health and Psychiatry.

    Simon, Frederick A J / Schenk, Maria / Palm, Denise / Faltraco, Frank / Thome, Johannes

    International journal of environmental research and public health

    2021  Volume 18, Issue 9

    Abstract: The potential consequences of the COVID-19 outbreak are multifarious and remain largely unknown. Deaths as a direct result of the condition are already in the millions, and the number of indirect deaths is likely to be even higher. Pre-existing ... ...

    Abstract The potential consequences of the COVID-19 outbreak are multifarious and remain largely unknown. Deaths as a direct result of the condition are already in the millions, and the number of indirect deaths is likely to be even higher. Pre-existing historical inequalities are compounded by the virus, driving increased rates of infection and deaths amongst people who use drugs and alcohol, those belonging to racial-ethnic minority groups, poorer communities, LBGTQ+ populations, healthcare workers, and other members of the care economy; all of whom are already at increased risk of adverse mental health effects. In this paper we suggest that a central role of mental health practitioners is advocacy: both for people who use psychiatric services and for those who, due to the effects of the pandemic, are at an increased risk of needing to do so.
    MeSH term(s) COVID-19 ; Disease Outbreaks ; Ethnic Groups ; Humans ; Mental Health ; Minority Groups ; Psychiatry ; SARS-CoV-2
    Language English
    Publishing date 2021-04-22
    Publishing country Switzerland
    Document type Journal Article
    ISSN 1660-4601
    ISSN (online) 1660-4601
    DOI 10.3390/ijerph18094440
    Database MEDical Literature Analysis and Retrieval System OnLINE

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