Publications by authors named "Thomas Jansen"

196 Publications

Doxorubicin induces wide-spread transcriptional changes in the myocardium of hearts distinguishing between mice with preserved and impaired cardiac function.

Life Sci 2021 Aug 11;284:119879. Epub 2021 Aug 11.

Department of Cardiology, Cardiology I, University Medical Center Mainz, Mainz, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhine-Main, Mainz, Germany. Electronic address:

Aims: Doxorubicin (DOX) is an important drug for the treatment of various tumor entities. However, the occurrence of heart failure limits its application. This study investigated differential gene expression profiles in the left and right ventricles of DOX treated mice with either preserved or impaired myocardial function. We provide new mechanistic insights into the pathophysiology of DOX-induced heart failure and have discovered pathways that counteract DOX-induced cardiotoxicity.

Main Methods: We used in total 48 male mice and applied a chronic low dose DOX administration (5 mg/kg per injection, in total 20 mg/kg over 4 weeks) to induce heart failure. Echocardiographic parameters were evaluated one week after the final dose and mice were separated according to functional parameters into doxorubicin responding and non-responding animals. Post mortem, measurements of reactive oxygen species (ROS) and gene expression profiling was performed in separated right and left hearts.

Key Findings: We detected significant ROS production in the left heart of the mice in response to DOX treatment, although interestingly, not in the right heart. We found that transcriptional changes differ between right and left heart correlating with the occurrence of myocardial dysfunction.

Significance: Doxorubicin induces changes in gene expression in the entire heart of animals without necessarily impairing cardiac function. We identified a set of transcripts that are associated with DOX cardiotoxicity. These might represent promising targets to ameliorate DOX-induced heart failure. Moreover, our results emphasize that parameters of left and right heart function should be evaluated during standardized echocardiography in patients undergoing DOX therapy.
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http://dx.doi.org/10.1016/j.lfs.2021.119879DOI Listing
August 2021

Was Fingernägel über die Niere verraten.

Authors:
Thomas Jansen

MMW Fortschr Med 2021 Aug;163(14)

Facharzt für Dermatologie, Höntroper Str. 102, 44869, Bochum, Deutschland.

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http://dx.doi.org/10.1007/s15006-021-0098-yDOI Listing
August 2021

Quantum-Classical Simulation of Molecular Motors Driven Only by Light.

J Phys Chem Lett 2021 Jun 7;12(23):5512-5518. Epub 2021 Jun 7.

University of Groningen, Zernike Institute for Advanced Materials, 9747 AG Groningen, The Netherlands.

Molecular motors that exhibit controlled unidirectional rotation provide great prospects for many types of applications, including nanorobotics. Existing rotational motors have two key components: photoisomerization around a π-bond followed by a thermally activated helical inversion, the latter being the rate-determining step. We propose an alternative molecular system in which the rotation is caused by the electric coupling of chromophores. This is used to engineer the excited state energy surface and achieve unidirectional rotation using light as the only input and avoid the slow thermally activated step, potentially leading to much faster operational speeds. To test the working principle, we employ quantum-classical calculations to study the dynamics of such a system. We estimate that motors built on this principle should be able to work on a subnanosecond time scale for such a full rotation. We explore the parameter space of our model to guide the design of a molecule that can act as such a motor.
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http://dx.doi.org/10.1021/acs.jpclett.1c00951DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8279737PMC
June 2021

Multiscale modeling of molecular structure and optical properties of complex supramolecular aggregates.

Chem Sci 2020 Oct 1;11(42):11514-11524. Epub 2020 Oct 1.

University of Groningen, Zernike Institute for Advanced Materials Groningen The Netherlands

Supramolecular aggregates of synthetic dye molecules offer great perspectives to prepare biomimetic functional materials for light-harvesting and energy transport. The design is complicated by the fact that structure-property relationships are hard to establish, because the molecular packing results from a delicate balance of interactions and the excitonic properties that dictate the optics and excited state dynamics, in turn sensitively depend on this packing. Here we show how an iterative multiscale approach combining molecular dynamics and quantum mechanical exciton modeling can be used to obtain accurate insight into the packing of thousands of cyanine dye molecules in a complex double-walled tubular aggregate in close interaction with its solvent environment. Our approach allows us to answer open questions not only on the structure of these prototypical aggregates, but also about their molecular-scale structural and energetic heterogeneity, as well as on the microscopic origin of their photophysical properties. This opens the route to accurate predictions of energy transport and other functional properties.
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http://dx.doi.org/10.1039/d0sc03110kDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8162738PMC
October 2020

Ethnic comparison in takotsubo syndrome: novel insights from the International Takotsubo Registry.

Clin Res Cardiol 2021 May 19. Epub 2021 May 19.

Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany.

Background: Ethnic disparities have been reported in cardiovascular disease. However, ethnic disparities in takotsubo syndrome (TTS) remain elusive. This study assessed differences in clinical characteristics between Japanese and European TTS patients and determined the impact of ethnicity on in-hospital outcomes.

Methods: TTS patients in Japan were enrolled from 10 hospitals and TTS patients in Europe were enrolled from 32 hospitals participating in the International Takotsubo Registry. Clinical characteristics and in-hospital outcomes were compared between Japanese and European patients.

Results: A total of 503 Japanese and 1670 European patients were included. Japanese patients were older (72.6 ± 11.4 years vs. 68.0 ± 12.0 years; p < 0.001) and more likely to be male (18.5 vs. 8.4%; p < 0.001) than European TTS patients. Physical triggering factors were more common (45.5 vs. 32.0%; p < 0.001), and emotional triggers less common (17.5 vs. 31.5%; p < 0.001), in Japanese patients than in European patients. Japanese patients were more likely to experience cardiogenic shock during the acute phase (15.5 vs. 9.0%; p < 0.001) and had a higher in-hospital mortality (8.2 vs. 3.2%; p < 0.001). However, ethnicity itself did not appear to have an impact on in-hospital mortality. Machine learning approach revealed that the presence of physical stressors was the most important prognostic factor in both Japanese and European TTS patients.

Conclusion: Differences in clinical characteristics and in-hospital outcomes between Japanese and European TTS patients exist. Ethnicity does not impact the outcome in TTS patients. The worse in-hospital outcome in Japanese patients, is mainly driven by the higher prevalence of physical triggers.

Trial Registration: URL: https://www.clinicaltrials.gov ; Unique Identifier: NCT01947621.
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http://dx.doi.org/10.1007/s00392-021-01857-4DOI Listing
May 2021

Neugeborenes mit seltsamem Ausschlag.

Authors:
Thomas Jansen

MMW Fortschr Med 2021 Mar;163(Suppl 1):11

Facharzt für Dermatologie, Höntroper Str. 102, 44869, Bochum, Deutschland.

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http://dx.doi.org/10.1007/s15006-021-9885-8DOI Listing
March 2021

Lessons from combined experimental and theoretical examination of the FTIR and 2D-IR spectroelectrochemistry of the amide I region of cytochrome c.

J Chem Phys 2021 Mar;154(12):124201

Institut für Biophysik, Johann-Wolfgang-Goethe-Universität, Max-von-Laue-Strasse. 1, 60438 Frankfurt am Main, Germany.

Amide I difference spectroscopy is widely used to investigate protein function and structure changes. In this article, we show that the common approach of assigning features in amide I difference signals to distinct secondary structure elements in many cases may not be justified. Evidence comes from Fourier transform infrared (FTIR) and 2D-IR spectroelectrochemistry of the protein cytochrome c in the amide I range, in combination with computational spectroscopy based on molecular dynamics (MD) simulations. This combination reveals that each secondary structure unit, such as an alpha-helix or a beta-sheet, exhibits broad overlapping contributions, usually spanning a large part of the amide I region, which in the case of difference absorption experiments (such as in FTIR spectroelectrochemistry) may lead to intensity-compensating and even sign-changing contributions. We use cytochrome c as the test case, as this small electron-transferring redox-active protein contains different kinds of secondary structure units. Upon switching its redox-state, the protein exhibits a different charge distribution while largely retaining its structural scaffold. Our theoretical analysis suggests that the change in charge distribution contributes to the spectral changes and that structural changes are small. However, in order to confidently interpret FTIR amide I difference signals in cytochrome c and proteins in general, MD simulations in combination with additional experimental approaches such as isotope labeling, the insertion of infrared labels to selectively probe local structural elements will be required. In case these data are not available, a critical assessment of previous interpretations of protein amide I 1D- and 2D-IR difference spectroscopy data is warranted.
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http://dx.doi.org/10.1063/5.0039969DOI Listing
March 2021

An Lippen und Zunge treten Knötchen auf.

Authors:
Thomas Jansen

MMW Fortschr Med 2021 Mar;163(5)

Facharzt für Dermatologie, Höntroper Str. 102, 44869, Bochum, Germany.

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http://dx.doi.org/10.1007/s15006-021-9702-4DOI Listing
March 2021

Exciton localization in tubular molecular aggregates: Size effects and optical response.

J Chem Phys 2020 May;152(19):194302

Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.

We study the exciton localization and resulting optical response for disordered tubular aggregates of optically active molecules. It has previously been shown that such tubular structures allow for excitons delocalized over more than a thousand molecules, owing to the combined effects of long-range dipole-dipole interactions and the higher-dimensional (not truly one-dimensional) nature of the aggregate. Such large delocalization sizes prompt the question to what extent in experimental systems the delocalization may still be determined by the aggregate size (diameter and length) and how this affects the aggregate's optical response and dynamics. We perform a systematic study of the size effects on the localization properties using numerical simulations of the exciton states in a cylindrical model structure inspired by the previously derived geometry of a cylindrical aggregate of cyanine dye molecules (C8S3). To characterize the exciton localization, we calculate the participation ratio and the autocorrelation function of the exciton wave function. We also calculate the density of states and absorption spectrum. We find strong effects of the tube's radius on the localization and optical properties in the range of parameters relevant to the experiment. In addition, surprisingly, we find that even for tubes as long as 750 nm, the localization size is limited by the tube's length for disorder values that are relevant to experimental circumstances, while observable effects of the tube's length in the absorption spectrum still occur for tube lengths up to about 150 nm. The latter may explain the changes in the optical spectra observed during the aging process of bromine-substituted C8S3 aggregates. For weak disorder, the exciton wave functions exhibit a scattered, fractal-like nature, similar to the quasi-particles in two-dimensional disordered systems.
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http://dx.doi.org/10.1063/5.0008688DOI Listing
May 2020

An Exciton Dynamics Model of Light-Harvesting Complex II.

J Phys Chem B 2021 02 22;125(4):1134-1143. Epub 2021 Jan 22.

Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371.

is a marine green macroalga adapted to the intertidal environment. It possesses siphonaxanthin-binding light-harvesting complexes of photosystem II (LHCII) with spectroscopic properties markedly different from the LHCII in plants. By applying a phenomenological fitting procedure to the two-dimensional electronic spectra of the LHCII from measured at 77 K, we can extract information about the excitonic states and energy-transfer processes. The fitting method results in well-converged parameters, including excitonic energy levels with their respective transition dipole moments, spectral widths, energy-transfer rates, and coupling properties. The 2D spectra simulated from the fitted parameters concur very well with the experimental data, showing the robustness of the fitting method. An excitonic energy-transfer scheme can be constructed from the fitting parameters. It shows the rapid energy transfer from chlorophylls (Chls) to at subpicosecond time scales and a long-lived state in the Chl region at around 659 nm. Three weakly connected terminal states are resolved at 671, 675, and 677 nm. The lowest state is higher in energy than that in plant LHCII, which is probably because of the fewer number of Chls in a LHCII monomer. Modeling based on existing Hamiltonians for the plant LHCII structure with two Chls switched to Chls suggests several possible Chl - replacements in comparison with those of plant LHCII. The adaptive changes result in a slower energy equilibration in the complex, revealed by the longer relaxation times of several exciton states compared to those of plant LHCII. The strength of our phenomenological fitting method for obtaining excitonic energy levels and energy-transfer network is put to the test in systems such as LHCII, where prior knowledge on exact assignment and spatial locations of pigments are lacking.
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http://dx.doi.org/10.1021/acs.jpcb.0c10634DOI Listing
February 2021

Excited state dynamics and exciton diffusion in triphenylamine/dicyanovinyl push-pull small molecule for organic optoelectronics.

Sci Rep 2020 Dec 3;10(1):21198. Epub 2020 Dec 3.

Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, the Netherlands.

Triphenylamine-based small push-pull molecules have recently attracted substantial research attention due to their unique optoelectronic properties. Here, we investigate the excited state de-excitation dynamics and exciton diffusion in TPA-T-DCV-Ph-F small molecule, having simple chemical structure with asymmetrical architecture and end-capped with electron-withdrawing p-fluorodicyanovinyl group. The excited state lifetime in diluted solutions (0.04 ns in toluene and 0.4 ns in chloroform) are found to be surprisingly shorter compared to the solid state (3 ns in PMMA matrix). Time-dependent density functional theory indicates that this behavior originates from non-radiative relaxation of the excited state through a conical intersection between the ground and singlet excited state potential energy surfaces. Exciton diffusion length of ~ 16 nm in solution processed films was retrieved by employing time-resolved photoluminescence volume quenching measurements with Monte Carlo simulations. As means of investigating the device performance of TPA-T-DCV-Ph-F, we manufactured solution and vacuum processed bulk heterojunction solar cells that yielded efficiencies of ~ 1.5% and ~ 3.7%, respectively. Our findings demonstrate that the short lifetime in solutions does not hinder per se long exciton diffusion length in films thereby granting applications of TPA-T-DCV-Ph-F and similar push-pull molecules in vacuum and solution processable devices.
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http://dx.doi.org/10.1038/s41598-020-78197-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7713310PMC
December 2020

Am Knie bildet sich eine seltsame Narbe.

Authors:
Thomas Jansen

MMW Fortschr Med 2020 Nov;162(Suppl 3):11

, Höntroper Str. 102, 44869, Bochum, Deutschland.

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http://dx.doi.org/10.1007/s15006-020-4541-2DOI Listing
November 2020

Observation of Ultrafast Coherence Transfer and Degenerate States with Polarization-Controlled Two-Dimensional Electronic Spectroscopy.

J Phys Chem B 2020 10 9;124(42):9420-9427. Epub 2020 Oct 9.

Zernike Institute for Advanced Materials, University of Groningen, 9747 AG Groningen, The Netherlands.

Optical spectroscopy is a powerful tool to interrogate quantum states of matter. We present simulation results for the cross-polarized two-dimensional electronic spectra of the light-harvesting system LH2 of purple bacteria. We identify a spectral feature on the diagonal, which we assign to ultrafast coherence transfer between degenerate states. The implication for the interpretation of previous experiments on different systems and the potential use of this feature are discussed. In particular, we foresee that this kind of feature will be useful for identifying mixed degenerate states and for identifying the origin of symmetry breaking disorder in systems like LH2. Furthermore, this may help identify both vibrational and electronic states in biological systems such as proteins and solid-state materials such as hybrid perovskites.
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http://dx.doi.org/10.1021/acs.jpcb.0c08126DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7586392PMC
October 2020

Molecular versus Excitonic Disorder in Individual Artificial Light-Harvesting Systems.

J Am Chem Soc 2020 10 9;142(42):18073-18085. Epub 2020 Oct 9.

Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.

Natural light-harvesting antennae employ a dense array of chromophores to optimize energy transport via the formation of delocalized excited states (excitons), which are critically sensitive to spatio-energetic variations of the molecular structure. Identifying the origin and impact of such variations is highly desirable for understanding and predicting functional properties yet hard to achieve due to averaging of many overlapping responses from individual systems. Here, we overcome this problem by measuring the heterogeneity of synthetic analogues of natural antennae-self-assembled molecular nanotubes-by two complementary approaches: single-nanotube photoluminescence spectroscopy and ultrafast 2D correlation. We demonstrate remarkable homogeneity of the nanotube ensemble and reveal that ultrafast (∼50 fs) modulation of the exciton frequencies governs spectral broadening. Using multiscale exciton modeling, we show that the dominance of homogeneous broadening at the exciton level results from exchange narrowing of strong static disorder found for individual molecules within the nanotube. The detailed characterization of static and dynamic disorder at the exciton as well as the molecular level presented here opens new avenues in analyzing and predicting dynamic exciton properties, such as excitation energy transport.
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http://dx.doi.org/10.1021/jacs.0c07392DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7582617PMC
October 2020

Safety of transradial and transfemoral left ventricular compared with transfemoral right ventricular endomyocardial biopsy.

ESC Heart Fail 2020 Sep 19. Epub 2020 Sep 19.

Department of Cardiology, University Medical Center Mainz, Langenbeckstr. 1, Mainz, 55131, Germany.

Aims: With the present study, we sought to determine the safety of three different endomyocardial biopsy (EMB) access routes in 514 patients admitted for diagnostic workup of heart failure of unknown aetiology.

Methods And Results: In this retrospective monocentric cohort study, we analysed 514 consecutive patients with heart failure without evidence of significant coronary artery disease or valvular disease undergoing EMB between November 2013 and December 2018, stratified in three access route groups: transradial arterial left ventricular (LV-)EMB (323 patients), transfemoral LV-EMB (138 patients), and transfemoral right ventricular (RV-)EMB (53 patients). Patients undergoing selective transradial LV-EMB were older compared with patients undergoing selective transfemoral LV-EMB or RV-EMB [transradial LV-EMB: 56.0 (45.0/64.0) vs. transfemoral LV-EMB: 53 (42.5/64.5), P = 0.455; transradial LV-EMB: 56 (45.0/64.0) vs. RV-EMB: 53 (42.5/64), P = 0.695] and presented more often in New York Heart Association-functional class III and IV. A total of eight major complications including permanent atrioventricular block requiring pacemaker implantation, pericardial tamponade necessitating pericardiocentesis, stroke and transient cerebral ischaemic attack as well as severe valvular damage, vascular access site complications, and ventricular fibrillation were documented with no significant differences between the groups (8/514, 1.5%). Minor complications such as transient chest pain, non-sustained electrocardiogram abnormalities, and transient atrioventricular block were rare and equally distributed between groups.

Conclusions: Transradial LV-EMB is a safe procedure for experienced radial operators and non-inferior compared with transfemoral LV-EMB and RV-EMB. An accurate peri-procedural and post-procedural monitoring and follow-up care should be recommended for all patients undergoing this procedure in order to identify potential complications.
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http://dx.doi.org/10.1002/ehf2.13006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7754772PMC
September 2020

Vibrational Spectroscopic Map, Vibrational Spectroscopy, and Intermolecular Interaction.

Chem Rev 2020 08 29;120(15):7152-7218. Epub 2020 Jun 29.

Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706-1396, United States.

Vibrational spectroscopy is an essential tool in chemical analyses, biological assays, and studies of functional materials. Over the past decade, various coherent nonlinear vibrational spectroscopic techniques have been developed and enabled researchers to study time-correlations of the fluctuating frequencies that are directly related to solute-solvent dynamics, dynamical changes in molecular conformations and local electrostatic environments, chemical and biochemical reactions, protein structural dynamics and functions, characteristic processes of functional materials, and so on. In order to gain incisive and quantitative information on the local electrostatic environment, molecular conformation, protein structure and interprotein contacts, ligand binding kinetics, and electric and optical properties of functional materials, a variety of vibrational probes have been developed and site-specifically incorporated into molecular, biological, and material systems for time-resolved vibrational spectroscopic investigation. However, still, an all-encompassing theory that describes the vibrational solvatochromism, electrochromism, and dynamic fluctuation of vibrational frequencies has not been completely established mainly due to the intrinsic complexity of intermolecular interactions in condensed phases. In particular, the amount of data obtained from the linear and nonlinear vibrational spectroscopic experiments has been rapidly increasing, but the lack of a quantitative method to interpret these measurements has been one major obstacle in broadening the applications of these methods. Among various theoretical models, one of the most successful approaches is a semiempirical model generally referred to as the vibrational spectroscopic map that is based on a rigorous theory of intermolecular interactions. Recently, genetic algorithm, neural network, and machine learning approaches have been applied to the development of vibrational solvatochromism theory. In this review, we provide comprehensive descriptions of the theoretical foundation and various examples showing its extraordinary successes in the interpretations of experimental observations. In addition, a brief introduction to a newly created repository Web site (http://frequencymap.org) for vibrational spectroscopic maps is presented. We anticipate that a combination of the vibrational frequency map approach and state-of-the-art multidimensional vibrational spectroscopy will be one of the most fruitful ways to study the structure and dynamics of chemical, biological, and functional molecular systems in the future.
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http://dx.doi.org/10.1021/acs.chemrev.9b00813DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7710120PMC
August 2020

Er trägt das Herz am falschen Fleck.

Authors:
Thomas Jansen

MMW Fortschr Med 2020 Jun;162(12)

, Höntroper Str. 102, D-44869, Bochum, Deutschland.

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http://dx.doi.org/10.1007/s15006-020-0592-7DOI Listing
June 2020

The AMP-Activated Protein Kinase Plays a Role in Antioxidant Defense and Regulation of Vascular Inflammation.

Antioxidants (Basel) 2020 Jun 16;9(6). Epub 2020 Jun 16.

Center for Cardiology, Department of Cardiology 1-Molecular Cardiology, University Medical Center, Johannes Gutenberg University, 55131 Mainz, Germany.

Cardiovascular diseases represent the leading cause of global deaths and life years spent with a severe disability. Endothelial dysfunction and vascular oxidative stress are early precursors of atherosclerotic processes in the vascular wall, all of which are hallmarks in the development of cardiovascular diseases and predictors of future cardiovascular events. There is growing evidence that inflammatory processes represent a major trigger for endothelial dysfunction, vascular oxidative stress and atherosclerosis and clinical data identified inflammation as a cardiovascular risk factor on its own. AMP-activated protein kinase (AMPK) is a central enzyme of cellular energy balance and metabolism that has been shown to confer cardio-protection and antioxidant defense which thereby contributes to vascular health. Interestingly, AMPK is also redox-regulated itself. We have previously shown that AMPK largely contributes to a healthy endothelium, confers potent antioxidant effects and prevents arterial hypertension. Recently, we provided deep mechanistic insights into the role of AMPK in cardiovascular protection and redox homeostasis by studies on arterial hypertension in endothelial and myelomonocytic cell-specific AMPK knockout (Cadh5CrexAMPKfl/fl and LysMCrexAMPKfl/fl) mice. Using these cell-specific knockout mice, we revealed the potent anti-inflammatory properties of AMPK representing the molecular basis of the antihypertensive effects of AMPK. Here, we discuss our own findings in the context of literature data with respect to the anti-inflammatory and antioxidant effects of AMPK in the specific setting of arterial hypertension as well as cardiovascular diseases in general.
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http://dx.doi.org/10.3390/antiox9060525DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7346208PMC
June 2020

Quantum biology revisited.

Sci Adv 2020 04 3;6(14):eaaz4888. Epub 2020 Apr 3.

Chemical Physics, Box 124, Lund University, 22100 Lund, Sweden.

Photosynthesis is a highly optimized process from which valuable lessons can be learned about the operating principles in nature. Its primary steps involve energy transport operating near theoretical quantum limits in efficiency. Recently, extensive research was motivated by the hypothesis that nature used quantum coherences to direct energy transfer. This body of work, a cornerstone for the field of quantum biology, rests on the interpretation of small-amplitude oscillations in two-dimensional electronic spectra of photosynthetic complexes. This Review discusses recent work reexamining these claims and demonstrates that interexciton coherences are too short lived to have any functional significance in photosynthetic energy transfer. Instead, the observed long-lived coherences originate from impulsively excited vibrations, generally observed in femtosecond spectroscopy. These efforts, collectively, lead to a more detailed understanding of the quantum aspects of dissipation. Nature, rather than trying to avoid dissipation, exploits it via engineering of exciton-bath interaction to create efficient energy flow.
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http://dx.doi.org/10.1126/sciadv.aaz4888DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7124948PMC
April 2020

Akutes Exanthem bei einem Kleinkind.

Authors:
Thomas Jansen

MMW Fortschr Med 2020 Apr;162(6)

, Höntroper Straße 102, D-44869, Bochum, Deutschland.

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http://dx.doi.org/10.1007/s15006-020-0314-1DOI Listing
April 2020

Blinder Passagier vom Strand in Thailand.

Authors:
Thomas Jansen

MMW Fortschr Med 2020 Feb;162(3)

, Höntroper Str. 102, D-44869, Bochum, Deutschland.

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http://dx.doi.org/10.1007/s15006-020-0128-1DOI Listing
February 2020

Effect of a Strategy of Comprehensive Vasodilation vs Usual Care on Mortality and Heart Failure Rehospitalization Among Patients With Acute Heart Failure: The GALACTIC Randomized Clinical Trial.

JAMA 2019 12;322(23):2292-2302

Department of Cardiology and Cardiovascular Research Institute Basel (CRIB), University Hospital Basel, University of Basel, Basel, Switzerland.

Importance: Short-term infusions of single vasodilators, usually given in a fixed dose, have not improved outcomes in patients with acute heart failure (AHF).

Objective: To evaluate the effect of a strategy that emphasized early intensive and sustained vasodilation using individualized up-titrated doses of established vasodilators in patients with AHF.

Design, Setting, And Participants: Randomized, open-label blinded-end-point trial enrolling 788 patients hospitalized for AHF with dyspnea, increased plasma concentrations of natriuretic peptides, systolic blood pressure of at least 100 mm Hg, and plan for treatment in a general ward in 10 tertiary and secondary hospitals in Switzerland, Bulgaria, Germany, Brazil, and Spain. Enrollment began in December 2007 and follow-up was completed in February 2019.

Interventions: Patients were randomized 1:1 to a strategy of early intensive and sustained vasodilation throughout the hospitalization (n = 386) or usual care (n = 402). Early intensive and sustained vasodilation was a comprehensive pragmatic approach of maximal and sustained vasodilation combining individualized doses of sublingual and transdermal nitrates, low-dose oral hydralazine for 48 hours, and rapid up-titration of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, or sacubitril-valsartan.

Main Outcomes And Measures: The primary end point was a composite of all-cause mortality or rehospitalization for AHF at 180 days.

Results: Among 788 patients randomized, 781 (99.1%; median age, 78 years; 36.9% women) completed the trial and were eligible for primary end point analysis. Follow-up at 180 days was completed for 779 patients (99.7%). The primary end point, a composite of all-cause mortality or rehospitalization for AHF at 180 days, occurred in 117 patients (30.6%) in the intervention group (including 55 deaths [14.4%]) and in 111 patients (27.8%) in the usual care group (including 61 deaths [15.3%]) (absolute difference for the primary end point, 2.8% [95% CI, -3.7% to 9.3%]; adjusted hazard ratio, 1.07 [95% CI, 0.83-1.39]; P = .59). The most common clinically significant adverse events with early intensive and sustained vasodilation vs usual care were hypokalemia (23% vs 25%), worsening renal function (21% vs 20%), headache (26% vs 10%), dizziness (15% vs 10%), and hypotension (8% vs 2%).

Conclusions And Relevance: Among patients with AHF, a strategy of early intensive and sustained vasodilation, compared with usual care, did not significantly improve a composite outcome of all-cause mortality and AHF rehospitalization at 180 days.

Trial Registration: ClinicalTrials.gov Identifier: NCT00512759.
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http://dx.doi.org/10.1001/jama.2019.18598DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6990838PMC
December 2019

Sein Bart wächst nicht mehr schön.

Authors:
Thomas Jansen

MMW Fortschr Med 2019 Nov;161(Suppl 3)

, Höntroper Str. 102, D-44869, Bochum, Deutschland.

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http://dx.doi.org/10.1007/s15006-019-1077-4DOI Listing
November 2019

Interplay between structural hierarchy and exciton diffusion in artificial light harvesting.

Nat Commun 2019 10 10;10(1):4615. Epub 2019 Oct 10.

University of Groningen, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.

Unraveling the nature of energy transport in multi-chromophoric photosynthetic complexes is essential to extract valuable design blueprints for light-harvesting applications. Long-range exciton transport in such systems is facilitated by a combination of delocalized excitation wavefunctions (excitons) and exciton diffusion. The unambiguous identification of the exciton transport is intrinsically challenging due to the system's sheer complexity. Here we address this challenge by employing a spectroscopic lab-on-a-chip approach: ultrafast coherent two-dimensional spectroscopy and microfluidics working in tandem with theoretical modeling. We show that at low excitation fluences, the outer layer acts as an exciton antenna supplying excitons to the inner tube, while under high excitation fluences the former converts its functionality into an exciton annihilator which depletes the exciton population prior to any exciton transfer. Our findings shed light on the excitonic trajectories across different sub-units of a multi-layered artificial light-harvesting complex and underpin their great potential for directional excitation energy transport.
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http://dx.doi.org/10.1038/s41467-019-12345-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6787233PMC
October 2019

Welche Art von Tumor wächst da am Bein?

Authors:
Thomas Jansen

MMW Fortschr Med 2019 Oct;161(17)

, Höntroper Str. 102, D-44869, Bochum, Deutschland.

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http://dx.doi.org/10.1007/s15006-019-0927-4DOI Listing
October 2019

Blau-schwarze Flecken an den Wangen.

Authors:
Thomas Jansen

MMW Fortschr Med 2019 Jun;161(12)

, Höntroper Str. 102, D-44869, Bochum, Deutschland.

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http://dx.doi.org/10.1007/s15006-019-0634-1DOI Listing
June 2019

Allylation of aldehydes by dual photoredox and nickel catalysis.

Chem Commun (Camb) 2019 Jun;55(48):6838-6841

Dipartimento di Chimica "G. Ciamician", ALMA MATER STUDIORUM Università di Bologna, Via Selmi 2, 40126 Bologna, Italy.

Here we report the application of dual nickel/photoredox catalysis to the allylation of aliphatic, aromatic and heteroaromatic aldehydes by using commercially available reagents. The process utilizes the combination of a Ni(ii) complex, [Ru(bpy)3]2+ as a photoredox catalyst, and allylacetate under blue LED irradiation, and allows the synthesis of a large variety of homoallylic alcohols.
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http://dx.doi.org/10.1039/c9cc03344kDOI Listing
June 2019

Red-emitting KHFWOF:Mn for application in warm-white phosphor-converted LEDs - optical properties and magnetic resonance characterization.

Dalton Trans 2019 Apr;48(16):5361-5371

Department of Chemical Engineering, Münster University of Applied Sciences, Stegerwaldstrasse 39, 48565 Steinfurt, Germany.

We report novel efficient Mn4+ phosphors of composition K3HF2MO2F4:Mn4+ (M = Mo, W) containing [HF2]- and octahedral [MO2F4]2- building units. The phosphor exhibits strong absorption at 450 nm and an external quantum yield of 90%. K3HF2WO2F4:0.01Mn4+ provides a sufficiently high quenching temperature T1/2 of about 400 K and is applicable as a converter for (In,Ga)N LEDs. The EPR spectrum is consistent with the presence of a MnF62- species at giso = 1.983. 19F MAS NMR results confirm the 2 : 1 ratio of the metal-bound fluoride species to the hydrogen difluoride group as predicted from the chemical formula. There are two distinct M-bonded species in a 1 : 1 ratio, indicating that the W and Mo octahedra are exclusively of the MO2F42- type, with the two oxygen atoms in cis-position. Their extremely sharp 19F resonances indicate a fast, near-isotropic reorientational process at room temperature that is on the millisecond timescale. For the HF2- group, the 19F and 1H MAS NMR spinning sideband profiles reveal the geometry of a linear centrosymmetric three-spin system with an H-F bond distance of 1.14 Å.
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http://dx.doi.org/10.1039/c9dt00091gDOI Listing
April 2019

Schwarze Sprenkel an der Ferse.

Authors:
Thomas Jansen

MMW Fortschr Med 2019 Mar;161(Suppl 1)

, Höntroper Str. 102, D-44869, Bochum, Deutschland.

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http://dx.doi.org/10.1007/s15006-019-0296-zDOI Listing
March 2019
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