bluuebunny/crossref_metadata_2025_split huggingface dataset:
N-3 Fettsäuren, Eikosanoide und zelluläre Funktionen
Authors: Fischer S. , Lorenz R. , Weber P. C. , v. Schacky C. 
Published: June 2018

ZusammenfassungIn geeigneten In-vitro-Modellen und beim Menschen verändern n-3 Fettsäuren das Eikosanoidsystem qualitativ und quantitativ in eine günstige Richtung. Zusätzlich zur unverminderten Bildung der stark vasodilatatorisch und antiaggregatorisch wirksamen Substanz PGI2 erscheint in größeren Mengen das biologisch beinahe ebenso wirksame PGI3. Die Biosynthese des physiologischen Gegenspielers von PGI, der starke Aggregator und Vasokonstriktor TXA2, wird gesenkt, in kleinen Mengen wird auch ein biologisch nicht oder nur gering wirksames TXA3 gebildet. EPA wird im Menschen in den Neutrophilen eingebaut und auf Stimulation hin das schwach chemotaktisch und chemokinetisch wirksame LTB5 in geringen Mengen gebildet. Ob die Biosynthese des biologisch viel stärker wirksamen LTB4 dabei zurückgeht, ist gegenwärtig unklar. Man nimmt an, daß die qualitative und quantitative Umstellung des Eikosanoidsystems bei den in vielen Untersuchungen festgestellten günstigen Veränderungen zellulärer Funktionen während der Anreicherung der Ernährung mit n-3 Fettsäuren eine Rolle spielt. Noch zu erklären bleibt, wie die Thrombozytenaggregationshemmung nach DCHA mediiert wird.Durch eine Anreicherung der Ernährung mit n-3 Fettsäuren lassen sich bei Gesunden wie bei Patienten auch unter unseren Zivilisationsbedingungen funktionelle und biochemische Veränderungen erzielen, wie sie bei Eskimos oder Japanern beobachtet werden: So sinkt die Thrombozytenaggregation ex vivo, als In-vivo-Korrelat wird die Blutungszeit verlängert. Auch scheinen sich günstige Veränderungen bei Zellen, die bei Entzündung und immunologischen Erkrankungen eine Rolle spielen, einzustellen. Da n-3 Fettsäuren außerdem Blutfette senken, Blutdruck und Blutdruckantwort auf Pressorhormone senken und rheologische Parameter günstig verändern, ist zu vermuten, daß n-3 Fettsäuren einen Platz in Therapie und Prophylaxe der Atherosklerose finden werden. Zuvor gilt es allerdings Ergebnisse laufender Studien abzuwarten, die Dosierungen und genaue Indikationen festlegen werden.
Sind Kalziumionen unerläßlich für die Aktivierung der Blutplättchen?
Authors: Lüscher E. F. 
Published: June 2018

ZusammenfassungDie typischen Manifestationen aktivierter Blutplättchen basieren zum großen Teil auf kalziumabhängigen Reaktionen, und die Frage nach der Herkunft und der Art des Verfügbarwerdens freier Kalziumionen im Zell-innern stellt daher ein zentrales Problem dar. Die Plättchen enthalten ein als »dense tubular system« bezeichnetes Kalziumspeicherorgan, das durch Inositoltriphosphat (IP3) zur Abgabe von Ca2+-Ionen angeregt wird. IP3 entsteht durch Hydrolyse von Phosphatidylinositol-4,5-bisphosphat neben Diacylglycerin (DAG) unter dem Einfluß von Phospholipase C. Wegen der gleichzeitigen Bildung von DAG und IP3 ist ein von verschiedenen Autoren postulierter, alternativer Weg der Aktivierung, der statt auf der Mobilisierung von Ca2+-Ionen auf der Bildung einer mittels DAG aktivierten Proteinkinase C basiert, unter physiologischen Bedingungen nicht möglich. Als Folge der ersten Aktivierungsschritte strömen auch Kalziumionen von außen ins Zellinnere. Dieser Einstrom ist aber nicht unerläßlich.In neuerer Zeit wurde gefunden, daß eine Aktivierung des Plättchens auch ohne eine Erhöhung des Ruhespiegels des zytoplasmatischen Kalziums (10−7 M) möglich ist, sofern Guanosintriphosphat anwesend ist. Es ist daraus auf die Mitwirkung von G-(oder N-)Proteinen geschlossen worden, die Phospholipase C auch unter diesen Bedingungen aktivieren sollen. Es ist allerdings bemerkenswert, daß gereinigte Präparate dieses Enzyms kalziumabhängig sind, so daß zur Zeit die Frage offen bleibt, ob verschiedene Formen des Enzyms existieren, oder ob das G-Protein tatsächlich eine Aktivierung im praktisch kalziumfreien System zu bewirken vermag.
Plasma-Präkallikrein
Authors: Gallimore M. J. 
Published: June 2018

ZusammenfassungEinfache Untersuchungsmethoden für die Bestimmung der Spiegel des Plasma-Präkallikreins und anderer Komponenten der plasmatischen Abwehrsysteme sind jetzt verfügbar. Obwohl diese Tests bisher nicht voll in der Klinik verwendet wurden, so erhielt man doch eine Menge nützlicher Informationen mit Hilfe dieser Tests. Zahlreiche Laboratorien in Europa verwenden bereits diese Tests, um Patienten während Intensivbetreuung zu beobachten, und verwenden die Ergebnisse für die Entwicklung neuer Therapien. Weitere Zustände, in denen die Analyse der Komponenten dieser Systeme von Vorteil sein könnten, schließen die Organtransplantation, Lebererkrankungen, Nierenerkrankungen, die rheumatoide Arthritis, allergische Erkrankungen, Thrombosen, Hypertonie und koronare Herzerkrankung ein.
Genetic Risk Factors and Inhibitor Development in Hemophilia: What Is Known and Searching for the Unknown
Authors: Intrieri Mariano , Margaglione Maurizio 
Published: June 2018

AbstractOver the past few decades, important knowledge on why inhibitors develop and better information about significant risk factors have become available. A series of both genetic and nongenetic factors are recognized and clinical score systems were proposed to quantify the risk for each patient. In addition, modulation of the immunological response was acknowledged to play a pivotal role in the occurrence of inhibitors. However, with the exception of mutation testing in severe hemophilia B patients, no single risk factor or clinical score is currently utilized in clinical practice. “Omics” technologies are large-scale hypothesis-generating approaches, which provide the tools to study issues contributing to a complex and multifactorial phenomenon, such as inhibitor development. Newer cutting edge technologies may enable a more accurate estimation of the personal risk profile and provide a reliable tool to accurately measure the risk periodically, thereby enabling strategies to foresee and prevent inhibitor formation.
Capsid protein structure, self-assembly, and processing reveal morphogenesis of the marine virophage mavirus
Authors: Born Diana , Reuter Lukas , Mersdorf Ulrike , Mueller Melanie , Fischer Matthias G. , Meinhart Anton , Reinstein Jochen 
Published: June 2018

Significance
Virophages are parasites of giant viruses within protists. They reduce giant virus production and increase host cell survival. They provide a defense system for protists against giant viruses in diverse environments, likely with ecological relevance for protist populations. To understand the remarkable virophage life cycle, it is crucial to investigate how they assemble into infectious particles and which processes require interactions with giant virus and host. We examined the marine virophage mavirus to show that its major and minor capsid proteins assemble into virus-like particles in the absence of specific host or viral factors. Subsequently, the virophage-encoded protease processes the major capsid protein to prepare virions for infection.
Costs, needs, and integration efforts shape helping behavior toward refugees
Authors: Böhm Robert , Theelen Maik M. P. , Rusch Hannes , Van Lange Paul A. M. 
Published: June 2018

Significance
The recent flow of refugees around the world evokes diametrically opposed reactions by the host countries’ citizens. Many people are willing to help refugees, whereas many others are not. Yet, the underlying mechanisms that lead to refugee helping versus rejection are not well understood. We use an economic game to investigate how economic and psychological factors shape citizens’ helping behavior toward refugees. We find that costs associated with refugee helping are a key determinant of citizens’ willingness to do so. It is especially people with a higher degree of prosociality that are willing to bear the personal cost of helping. Emphasizing the neediness of refugees as well as their integration efforts increases the willingness among citizens to provide help.
Key determinants of time to 5 m in different ventral swimming start techniques
Authors: Peterson Silveira Ricardo , Stergiou Pro , Figueiredo Pedro , Castro Flávio de S. , Katz Larry , Stefanyshyn Darren J. 
Published: June 2018

AbstractThe aim of this study was to determine the biomechanical parameters that explain ventral start performance in swimming. For this purpose, 13 elite swimmers performed different variants of the ventral start technique. Two‐dimensional video analyses of the aerial and underwater phases were used to assess 16 kinematic parameters from the starting signal to 5 m, and an instrumented starting block was used to assess kinetic data. A Lasso regression was used to reduce the number of parameters, providing the main determinants to starting performance, revealing different combinations of key determinants, depending on the variant (r² ≥ 0.90), with flight distance being the most relevant to all variants (r≤ −0.80;p< .001). Also, special attention should be given to the total horizontal impulse in the grab start (r= −0.79;p< .001) and to the back foot action in the track and kick starts (r≤ 0.61;p< .001). In addition, we provide two equations that could be easily used to predict starting performance by assessing block time and flight time (r² = 0.66) or block time and flight distance (r² = 0.83). These data provide relevant contributions to the further understanding of the biomechanics of swimming starts as well as insights for performance analysis and targeted interventions to improve athlete performance.
Current fluctuations and transport efficiency for general Langevin systems
Authors: Dechant Andreas , Sasa Shin-ichi 
Published: June 2018

Abstract
We derive a universal bound on generalized currents in Langevin systems in terms of the mean-square fluctuations of the current and the total entropy production. This bound generalizes a relation previously found by Barato et al to arbitrary times and transient states. Using the bound, we define a new efficiency for stochastic transport, which measures how close a given system comes to saturating the bound. The existence of such a bounded efficiency implies that stochastic transport is unavoidably accompanied by a fluctuations and dissipation, which cannot be reduced arbitrarily. We apply the definition of transport efficiency to steady state particle transport and heat engines and show that the transport efficiency may approach unity at finite current, in contrast to the thermodynamic efficiency. Finally, we derive a bound on purely diffusive transport in terms of the Shannon entropy.
The Virtues of Sunset Clauses in Relation to Constitutional Authority
Authors: Kouroutakis Antonios 
Published: June 2018

Abstract
This article focuses on the virtues of sunset clauses pertaining to authority. It examines the utility of such clauses in three instances: first, when there is a transfer of constitutional authority; secondly, when there is an exclusively attributed authority, but it is not exercised; and thirdly, when there is a creation of a new authority. In the case of a transfer of authority subject to sunset clauses, unless such authority is re-authorized, the sunset clause brings about its expiration on a prescribed date. In practice, the benefits from the sunset clause are twofold. First, such a clause allows the comprehensive evaluation of the transferred authority, minimizing the risk of any abuse. Secondly, such a clause sets the timetable, which promotes legal certainty. In the case of inactivity while there is an exclusive authority, the use of a sunset clause as an alarm clock creates an incentive for action; or alternatively, with the expiration of the sunset clause, the authority is considered ipso jure and simultaneously exercised. Finally, in the case where new authority is created, such authority may be subject to a sunset clause if it is implemented as a constitutional experiment or if it is controversial in nature because it possibly distorts the system of separation of powers.
What can Andreev bound states tell us about superconductors?
Authors: Millo Oded , Koren Gad 
Published: June 2018

Zero-energy Andreev bound states, which manifest themselves in the tunnelling spectra as zero-bias conductance peaks (ZBCPs), are abundant at interfaces between superconductors and other materials and on the nodal surface of high-temperature superconductors. In this review, we focus on the information such excitations can provide on the properties of superconductor systems. First, a general introduction to the physics of Andreev bound states in superconductor/normal metal interfaces is given with a particular emphasis on why they appear at zero energy in
d
-wave superconductors. Then, specific spectroscopic tunnelling studies of thin films, bilayers and junctions are described, focusing on the corresponding ZBCP features. Scanning tunnelling spectroscopy (STS) studies show that the ZBCPs on the
c
-axis YBa
2
Cu
3
O
7−

δ

(YBCO) films are correlated with the surface morphology and appear only in proximity to (110) facets. STS on
c
-axis La
1.88
Sr
0.12
CuO
4
(LSCO) films exhibiting the 1/8 anomaly shows spatially modulated peaks near zero bias associated with the anti-phase ordering of the
d
-wave order parameter predicted at this doping level. ZBCPs were also found in micrometre-size edge junctions of YBCO/SrRuO
3
/YBCO, where SrRuO
3
is ferromagnetic. Here, the results are consistent with a crossed Andreev reflection effect (CARE) at the narrow domain walls of the SrRuO
3
. ZBCPs measured in STS studies of manganite/cuprate bilayers could not be attributed to CARE because the manganite's domain wall is much larger than the coherence length in YBCO, and instead are attributed to proximity-induced triplet-pairing superconductivity with non-conventional symmetry. And finally, ZBCPs found in junctions of non-intentionally doped topological insulator films of Bi
2
Se
3
and the
s
-wave superconductor NbN are attributed to proximity-induced

p
x
+
i
p
y

triplet order parameter in the topological material.

This article is part of the theme issue ’Andreev bound states’.
Theory of Andreev bound states in S-F-S junctions and S-F proximity devices
Authors: Eschrig M. 
Published: June 2018

Andreev bound states are an expression of quantum coherence between particles and holes in hybrid structures composed of superconducting and non-superconducting metallic parts. Their spectrum carries important information on the nature of the pairing, and determines the current in Josephson devices. Here, I focus on Andreev bound states in systems involving superconductors and ferromagnets with strong spin-polarization. I provide a general framework for non-local Andreev phenomena in such structures in terms of coherence functions, and show how the latter link wave function and Green-function based theories.
This article is part of the theme issue ‘Andreev bound states’.
Morphological, cellular and molecular characterization of posterior regeneration in the marine annelid Platynereis dumerilii
Authors: Planques Anabelle , Malem Julien , Parapar Julio , Vervoort Michel , Gazave Eve 
Published: June 2018

ABSTRACTRegeneration, the ability to restore body parts after an injury or an amputation, is a widespread but highly variable and complex phenomenon in animals. While having fascinating scientists for centuries, fundamental questions about the cellular basis of animal regeneration as well as its evolutionary history remain largely unanswered. We study regeneration of the marine annelid Platynereis dumerilii, an emerging comparative developmental biology model, which, like many other annelids, displays important regenerative abilities. If the posterior part of the body is amputated, P. dumerilii worms are able to regenerate the posteriormost differentiated part of the body and stem cell-rich growth zone that allows to make new segments which replace the amputated ones. We show that posterior regeneration is a rapid process that follows a well reproducible paths and timeline, going through specific stages that we thoroughly defined. Wound healing is achieved by one day post-amputation and a regeneration blastema forms one day later. At this time point, some tissue specification already occurs, and a functional posterior growth zone is re-established as early as three days after amputation. Regeneration is only influenced in a minor manner by worm size and position of the amputation site along the antero-posterior axis of the worm and regenerative abilities persist upon repeated amputations without important alterations of the process. We also show that intense cell proliferation occurs during regeneration and that cell divisions are strictly required for regeneration to normally proceed. Finally, through several 5-ethynyl-2’-deoxyuridine (EdU) pulse and chase experiments, we provide evidence in favor of a local origin of the blastema, whose constituting cells mostly derive from the segment immediately abutting the amputation plane. The detailed characterization of P. dumerilii posterior body regeneration presented in this article provides the foundation for future mechanistic and comparative studies of regeneration in this species.
Enhanced β-secretase processing of amyloid precursor protein in the skeletal muscle of ALS animal models
Authors: Yang Huaqiang 
Published: June 2018

ABSTRACTAmyotrophic lateral sclerosis (ALS) is a lethal neurodegenerative disorder primarily characterized by motor neuron degeneration and muscle paralysis. Several studies indicate that pathological changes in the skeletal muscle contribute to disease progression. We report a significant increase of β-secretase processing of amyloid precursor protein (APP) in the skeletal muscle but not the spinal cord or cerebral cortex of hSOD1 (G93A) transgenic ALS mouse models. Enhanced β-secretase processing of APP was manifested by up-regulated expression of βCTF, the 22-kd CTF of APP, and β-secretase processing enzyme, BACE1. Morphological analysis demonstrated that enhanced β-secretase processing of APP mainly occurred in the atrophic myofibers of ALS mice. We also observed a similar change in APP processing in an hSOD1 (G93A) transgenic ALS pig model, suggesting that enhanced β-secretase processing of APP in skeletal muscle may be a common pathological feature of ALS. These findings reveal a selective change in APP processing in skeletal muscle of ALS animal models, and highlight the involvement of aberrant APP processing in ALS pathogenesis.
Implication of exofacial thiol groups in the reducing activity ofListeria monocytogenes
Authors: Pillot Guillaume , Brillet-Viel Anne , Prévost Hervé 
Published: June 2018

AbstractListeria monocytogenesgrowing in BHI in anaerobic condition leads a decrease of redox potential at pH7 (Eh7) from 0 to −250 mV. An investigation of mechanisms involved in this reducing activity shows the implication of thiol groups located on the bacterial cell surface. Indeed, after reduction of media to −250 mV, only thiol-reactive reagents could restore the initialEh7value. Moreover, the growth ofL. monocytogenesin anaerobic condition is characterized by a reduction then acidification phases. This suggests a sensor mechanism of environmentalEh7to convert the metabolism way from the first phase to the second. Finally, the concentration of exofacial thiol still increase strongly during the acidification phase ofL. monocytogenes, even after reach the minimal value ofEh7. These results suggest that maintaining the exofacial thiol (−SH) groups in a reduced state do not depend on an active mechanism. Thiol groups appear to be displayed by membrane proteins or cell wallbound proteins and may participate in protecting cells against oxidative stress.
“Stick-slip dynamics of cell adhesion triggers spontaneous symmetry breaking and directional migration”
Authors: Hennig K. , Wang I. , Moreau P. , Valon L. , DeBeco S. , Coppey M. , Miroshnikova Y. A. , Albiges-Rizo C. , Favard C. , Voituriez R. , Balland M. 
Published: June 2018

AbstractDirectional cell motility during organism and tissue development, homeostasis and disease requires symmetry breaking. This process relies on the ability of single cells to establish a front-rear polarity, and can occur in absence of external cues. The initiation of migration has been attributed to the spontaneous polarization of cytoskeleton components, while the spatiotemporal evolution of cytoskeletal forces arising from continuous mechanical cell-substrate interaction has yet to be resolved. Here, we establish a one-dimensional microfabricated migration assay that mimics complex in vivo fibrillar environment while being compatible with high-resolution force measurements, quantitative microscopy, and optogenetics. Quantification of morphometric and mechanical parameters reveals a generic stick-slip behavior initiated by contractility-dependent stochastic detachment of adhesive contacts at one side of the cell, which is sufficient to drive directional cell motility in absence of pre-established cytoskeleton polarity or morphogen gradients. A theoretical model validates the crucial role of adhesion dynamics during spontaneous symmetry breaking, proposing that the examined phenomenon can emerge independently of a complex self-polarizing system.One sentence summaryCells can autonomously break their symmetry through traction force oscillations (mechanical instabilities) that lead to stochastic detachment of adhesion patches on one side of the cell and the subsequent initiation of migration.
Reduced signal for polygenic adaptation of height in UK Biobank
Authors: Berg Jeremy J. , Harpak Arbel , Sinnott-Armstrong Nasa , Jørgensen Anja Moltke , Mostafavi Hakhamanesh , Field Yair , Boyle Evan A. , Zhang Xinjun , Racimo Fernando , Pritchard Jonathan K. , Coop Graham 
Published: June 2018

AbstractSeveral recent papers have reported strong signals of selection on European polygenic height scores. These analyses used height effect estimates from the GIANT consortium and replication studies. Here, we describe a new analysis based on the the UK Biobank (UKB), a large, independent dataset. We find that the signals of selection using UKB effect-size estimates for height are strongly attenuated or absent. We also provide evidence that previous analyses were confounded by population stratification Therefore, the conclusion of strong polygenic adaptation now lacks support. Moreover, these discrepancies highlight (1) that methods for correcting for population stratification in GWAS may not always be sufficient for polygenic trait analyses, and (2) that claims of differences in polygenic scores between populations should be treated with caution until these issues are better understood.
Signals of polygenic adaptation on height have been overestimated due to uncorrected population structure in genome-wide association studies
Authors: Sohail Mashaal , Maier Robert M. , Ganna Andrea , Bloemendal Alex , Martin Alicia R. , Turchin Michael C. , Chiang Charleston W. K. , Hirschhorn Joel N. , Daly Mark J. , Patterson Nick , Neale Benjamin M. , Mathieson Iain , Reich David , Sunyaev Shamil R. 
Published: June 2018

AbstractGenetic predictions of height differ among human populations and these differences are too large to be explained by genetic drift. This observation has been interpreted as evidence of polygenic adaptation. Differences across populations were detected using SNPs genome-wide significantly associated with height, and many studies also found that the signals grew stronger when large numbers of subsignificant SNPs were analyzed. This has led to excitement about the prospect of analyzing large fractions of the genome to detect subtle signals of selection and claims of polygenic adaptation for multiple traits. Polygenic adaptation studies of height have been based on SNP effect size measurements in the GIANT Consortium meta-analysis. Here we repeat the height analyses in the UK Biobank, a much more homogeneously designed study. Our results show that polygenic adaptation signals based on large numbers of SNPs below genome-wide significance are extremely sensitive to biases due to uncorrected population structure.