8 research outputs found

    Laser Spectroscopic Technique for Direct Identification of a Single Virus I: FASTER CARS

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    From the famous 1918 H1N1 influenza to the present COVID-19 pandemic, the need for improved virial detection techniques is all too apparent. The aim of the present paper is to show that identification of individual virus particles in clinical sample materials quickly and reliably is near at hand. First of all, our team has developed techniques for identification of virions based on a modular atomic force microscopy (AFM). Furthermore, Femtosecond Adaptive Spectroscopic Techniques with Enhanced Resolution via Coherent Anti-Stokes Raman Scattering (FASTER CARS) [1] using tip-enhanced techniques markedly improves the sensitivity.Comment: 16 pages, 3 figure

    Identification of RNA-containing virus particles using a triple correlative morphological and microscopic approach

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    Viral characterization based on different characteristics such as size or morphology is an important step towards a quick identification of virus infection. In this contribution, the identification and size determination of an isolated RNA virus with an atomic force microscope (AFM) in combination with conventional fluorescence microscopy is presented. Despite all the advantages of AFM for imaging individual viruses, discrimination by chemical composition and reliable differentiation of morphologically similar structures at the single particle level is hardly possible with the current state of the art. An effective method for identifying single virus particles based on their chemical structure is specific labeling and subsequent conventional fluorescence microscopic investigation. However, this method lacks morphologic information, and the resolution is generally above the virus size, impeding size determination. As a result, labeled hollow particles or viral fragments cannot be distinguished from intact particles of a similar size. In our experiments, the goal was to characterize and investigate the morphology, particularly the height of a model virus, here SARS-CoV-2 as an example, and unambiguously differentiate it from other sample components such as debris. The first step was topography mapping of inactivated virus samples using AFM. In the second step, the RNA-containing core and the spike proteins on the virus surface were labeled, and conventional fluorescence images were correlated with the topographic height images of the same particles, providing an accurate information about the actual stages of the viruses. As a main achievement, the experiments allow identification of individual intact SARS-CoV-2 particles and a distinction between viral fragments and potential false staining. The height range of virus particles under our specific inactivation conditions with paraformaldehyde treatment could be determined to be 60-110 nm. Following our results, pre-selection and distinction of viral particles from other sample components will be feasible by morphological characteristics alone, with a precision comparable to staining methods, prior to further specific identification. In general, our correlative approach combining information from scanning probe and conventional fluorescence microscopy can be applied to other virus strains as well, taken that virus-specific antibodies are known

    The translocator protein 18kDa ligand etifoxine in the treatment of depressive disorders—a double-blind, randomized, placebo-controlled proof-of-concept study

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    Background Recent developments suggest that neurosteroids may achieve rapid antidepressant effects. As such, neurosteroidogenesis mediated by the translocator protein 18 kDa (TSPO) might constitute a promising option for the treatment of depression. Therefore, the current clinical trial aims to get the first evidence of whether TPSO ligands promote rapid antidepressant effects. Furthermore, we study which mechanisms of action, e.g., modulation of distinct neuronal networks, neurosteroidogenesis, endocrinological mechanisms, TSPO expression or microbiome composition, contribute to their putative antidepressant effects. Methods This is a randomized, placebo-controlled, double-blind single-center trial of 2-week treatment with the TSPO ligand etifoxine versus placebo in depressive patients. Main eligibility criteria: male or female individuals aged 18 to 65 years with unipolar/bipolar depressive disorder with no other psychiatric main diagnosis or acute neurological/somatic disorder or drug/alcohol dependence during their lifetime. The primary endpoint is the time point at which 50% of the maximal effect has occurred (ET50) estimated by the scores of the Hamilton Depression Scale (HAMD-21). A total of 20 patients per group are needed to detect changes of therapeutic efficacy about 5% and changes of ET50 about 10% with a power of 70%. Assuming a drop-out rate of 10–20%, 50 patients will be randomized in total. The study will be conducted at the Department of Psychiatry and Psychotherapy of the University of Regensburg. Discussion This study will provide a first proof-of-concept on the potential of the TSPO ligand etifoxine in the treatment of depressive disorders. Trial registration Clinical Trials Register (EudraCT number: 2021-006773-38, registration date: 14 September 2022) and German Register of Clinical Studies (DRKS number: DRKS00031099, registration date: 23 January 2023)

    The translocator protein 18kDa ligand etifoxine in the treatment of depressive disorders—a double-blind, randomized, placebo-controlled proof-of-concept study

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    Abstract Background Recent developments suggest that neurosteroids may achieve rapid antidepressant effects. As such, neurosteroidogenesis mediated by the translocator protein 18 kDa (TSPO) might constitute a promising option for the treatment of depression. Therefore, the current clinical trial aims to get the first evidence of whether TPSO ligands promote rapid antidepressant effects. Furthermore, we study which mechanisms of action, e.g., modulation of distinct neuronal networks, neurosteroidogenesis, endocrinological mechanisms, TSPO expression or microbiome composition, contribute to their putative antidepressant effects. Methods This is a randomized, placebo-controlled, double-blind single-center trial of 2-week treatment with the TSPO ligand etifoxine versus placebo in depressive patients. Main eligibility criteria: male or female individuals aged 18 to 65 years with unipolar/bipolar depressive disorder with no other psychiatric main diagnosis or acute neurological/somatic disorder or drug/alcohol dependence during their lifetime. The primary endpoint is the time point at which 50% of the maximal effect has occurred (ET50) estimated by the scores of the Hamilton Depression Scale (HAMD-21). A total of 20 patients per group are needed to detect changes of therapeutic efficacy about 5% and changes of ET50 about 10% with a power of 70%. Assuming a drop-out rate of 10–20%, 50 patients will be randomized in total. The study will be conducted at the Department of Psychiatry and Psychotherapy of the University of Regensburg. Discussion This study will provide a first proof-of-concept on the potential of the TSPO ligand etifoxine in the treatment of depressive disorders. Trial registration Clinical Trials Register (EudraCT number: 2021-006773-38 , registration date: 14 September 2022) and German Register of Clinical Studies (DRKS number: DRKS00031099 , registration date: 23 January 2023)

    Validation of the DAPT score in patients randomized to 6 or 12 months clopidogrel after predominantly second-generation drug-eluting stents

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    The DAPT score is a recently-proposed decision tool for guiding optimal duration of dual antiplatelet therapy (DAPT). It showed modest accuracy in prior derivation and validation cohorts of patients with ≥12 months DAPT. This study was aimed to evaluate the validity of the DAPT score in a cohort of patients with 6 or 12 months DAPT after implantation of predominantly second-generation drug-eluting stents. We analyzed data of patients enrolled in the ISAR-SAFE trial. Patients were classified into low (<2) or high (≥2) DAPT score groups. Primary ischaemic (all-cause death, myocardial infarction, definite stent thrombosis or stroke) and bleeding (TIMI major or minor) outcomes were analyzed in the low and high DAPT score groups. Data of 3976 patients were available for DAPT score calculation. 2407 patients (60.5 %) were classified in the low DAPT score group and 1569 patients (39.5 %) in the high DAPT score group. In the low DAPT score group there were no significant differences between 6 and 12 months DAPT regarding ischaemic (1.0 % vs. 1.4 %, HR=0.74, 95 % CI, 0.35-1.57; p=0.43) or bleeding outcomes (0.3 % vs. 0.8 %, HR=0.44, 95 % CI, 0.13-1.42; p=0.17). In the high DAPT score group there were also no significant differences between 6 and 12 months DAPT regarding ischaemic (1.9 % vs. 1.8 %, HR=1.02, 95 % CI, 0.49-2.14; p=0.96) or bleeding (0.3 % vs. 0.5 %, HR=0.51, 95 % CI, 0.09-2.78; p=0.44) outcomes. In conclusion, the DAPT score failed to show a differential treatment effect in patients receiving 6 or 12 months DAPT after contemporary drug-eluting stent implantation.status: publishe

    Validation of the DAPT score in patients randomized to 6 or 12 months clopidogrel after predominantly second-generation drug-eluting stents

    No full text
    The DAPT score is a recently-proposed decision tool for guiding optimal duration of dual antiplatelet therapy (DAPT). It showed modest accuracy in prior derivation and validation cohorts of patients with >= 12 months DAPT. This study was aimed to evaluate the validity of the DAPT score in a cohort of patients with 6 or 12 months DAPT after implantation of predominantly second-generation drug-eluting stents. We analyzed data of patients enrolled in the ISAR-SAFE trial. Patients were classified into low (= 2) DAPT score groups. Primary ischaemic (all-cause death, myocardial infarction, definite stent thrombosis or stroke) and bleeding (TIMI major or minor) outcomes were analyzed in the low and high DAPT score groups. Data of 3976 patients were available for DAPT score calculation. 2407 patients (60.5 %) were classified in the low DAPT score group and 1569 patients (39.5%) in the high DAPT score group. In the low DAPT score group there were no significant differences between 6 and 12 months DAPT regarding ischaemic (1.0% vs. 1.4%, HR=0.74, 95% CI, 0.35-1.57; p=0.43) or bleeding outcomes (0.3 % vs. 0.8%, HR=0.44, 95 % CI, 0.13-1.42; p=0.17). In the high DAPT score group there were also no significant differences between 6 and 12 months DAPT regarding ischaemic (1.9% vs. 1.8%, HR=1.02, 95 % CI, 0.49-2.14; p=0.96) or bleeding (0.3 % vs. 0.5%, HR=0.51, 95 % CI, 0.09-2.78; p=0.44) outcomes. In conclusion, the DAPT score failed to show a differential treatment effect in patients receiving 6 or 12 months DAPT after contemporary drug-eluting stent implantation

    The Microbiome and Atopic Dermatitis: A Review

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