TY - JOUR A1 - Wilson, Duncan A1 - Ambler, Gareth A1 - Lee, Keon-Joo A1 - Lim, Jae-Sung A1 - Shiozawa, Masayuki A1 - Koga, Masatoshi A1 - Li, Linxin A1 - Lovelock, Caroline A1 - Chabriat, Hugues A1 - Hennerici, Michael A1 - Wong, Yuen Kwun A1 - Mak, Henry Ka Fung A1 - Prats-Sánchez, Luis A1 - Martínez-Domeño, Alejandro A1 - Inamura, Shigeru A1 - Yoshifuji, Kazuhisa A1 - Arsava, Ethem Murat A1 - Horstmann, Solveig A1 - Purrucker, Jan A1 - Lam, Bonnie Yin Ka A1 - Wong, Adrian A1 - Kim, Young Dae A1 - Song, Tae-Jin A1 - Schrooten, Maarten A1 - Lemmens, Robin A1 - Eppinger, Sebastian A1 - Gattringer, Thomas A1 - Uysal, Ender A1 - Tanriverdi, Zeynep A1 - Bornstein, Natan M A1 - Ben Assayag, Einor A1 - Hallevi, Hen A1 - Tanaka, Jun A1 - Hara, Hideo A1 - Coutts, Shelagh B A1 - Hert, Lisa A1 - Polymeris, Alexandros A1 - Seiffge, David J A1 - Lyrer, Philippe A1 - Algra, Ale A1 - Kappelle, Jaap A1 - Salman, Rustam Al-Shahi A1 - Jäger, Hans R A1 - Lip, Gregory Y H A1 - Mattle, Heinrich P A1 - Panos, Leonidas D A1 - Mas, Jean-Louis A1 - Legrand, Laurence A1 - Karayiannis, Christopher A1 - Phan, Thanh A1 - Gunkel, Sarah A1 - Christ, Nicolas A1 - Abrigo, Jill A1 - Leung, Thomas A1 - Chu, Winnie A1 - Chappell, Francesca A1 - Makin, Stephen A1 - Hayden, Derek A1 - Williams, David J A1 - Kooi, M Eline A1 - van Dam-Nolen, Dianne H K A1 - Barbato, Carmen A1 - Browning, Simone A1 - Wiegertjes, Kim A1 - Tuladhar, Anil M A1 - Maaijwee, Noortje A1 - Guevarra, Christine A1 - Yatawara, Chathuri A1 - Mendyk, Anne-Marie A1 - Delmaire, Christine A1 - Köhler, Sebastian A1 - van Oostenbrugge, Robert A1 - Zhou, Ying A1 - Xu, Chao A1 - Hilal, Saima A1 - Gyanwali, Bibek A1 - Chen, Christopher A1 - Lou, Min A1 - Staals, Julie A1 - Bordet, Régis A1 - Kandiah, Nagaendran A1 - de Leeuw, Frank-Erik A1 - Simister, Robert A1 - van der Lugt, Aad A1 - Kelly, Peter J A1 - Wardlaw, Joanna M A1 - Soo, Yannie A1 - Fluri, Felix A1 - Srikanth, Velandai A1 - Calvet, David A1 - Jung, Simon A1 - Kwa, Vincent I H A1 - Engelter, Stefan T A1 - Peters, Nils A1 - Smith, Eric E A1 - Yakushiji, Yusuke A1 - Necioglu Orken, Dilek A1 - Fazekas, Franz A1 - Thijs, Vincent A1 - Heo, Ji Hoe A1 - Mok, Vincent A1 - Veltkamp, Roland A1 - Ay, Hakan A1 - Imaizumi, Toshio A1 - Gomez-Anson, Beatriz A1 - Lau, Kui Kai A1 - Jouvent, Eric A1 - Rothwell, Peter M A1 - Toyoda, Kazunori A1 - Bae, Hee-Yoon A1 - Marti-Fabregas, Joan A1 - Werring, David J T1 - Cerebral microbleeds and stroke risk after ischaemic stroke or transient ischaemic attack: a pooled analysis of individual patient data from cohort studies JF - The Lancet Neurology N2 - Background Cerebral microbleeds are a neuroimaging biomarker of stroke risk. A crucial clinical question is whether cerebral microbleeds indicate patients with recent ischaemic stroke or transient ischaemic attack in whom the rate of future intracranial haemorrhage is likely to exceed that of recurrent ischaemic stroke when treated with antithrombotic drugs. We therefore aimed to establish whether a large burden of cerebral microbleeds or particular anatomical patterns of cerebral microbleeds can identify ischaemic stroke or transient ischaemic attack patients at higher absolute risk of intracranial haemorrhage than ischaemic stroke. Methods We did a pooled analysis of individual patient data from cohort studies in adults with recent ischaemic stroke or transient ischaemic attack. Cohorts were eligible for inclusion if they prospectively recruited adult participants with ischaemic stroke or transient ischaemic attack; included at least 50 participants; collected data on stroke events over at least 3 months follow-up; used an appropriate MRI sequence that is sensitive to magnetic susceptibility; and documented the number and anatomical distribution of cerebral microbleeds reliably using consensus criteria and validated scales. Our prespecified primary outcomes were a composite of any symptomatic intracranial haemorrhage or ischaemic stroke, symptomatic intracranial haemorrhage, and symptomatic ischaemic stroke. We registered this study with the PROSPERO international prospective register of systematic reviews, number CRD42016036602. Findings Between Jan 1, 1996, and Dec 1, 2018, we identified 344 studies. After exclusions for ineligibility or declined requests for inclusion, 20 322 patients from 38 cohorts (over 35 225 patient-years of follow-up; median 1·34 years [IQR 0·19–2·44]) were included in our analyses. The adjusted hazard ratio [aHR] comparing patients with cerebral microbleeds to those without was 1·35 (95% CI 1·20–1·50) for the composite outcome of intracranial haemorrhage and ischaemic stroke; 2·45 (1·82–3·29) for intracranial haemorrhage and 1·23 (1·08–1·40) for ischaemic stroke. The aHR increased with increasing cerebral microbleed burden for intracranial haemorrhage but this effect was less marked for ischaemic stroke (for five or more cerebral microbleeds, aHR 4·55 [95% CI 3·08–6·72] for intracranial haemorrhage vs 1·47 [1·19–1·80] for ischaemic stroke; for ten or more cerebral microbleeds, aHR 5·52 [3·36–9·05] vs 1·43 [1·07–1·91]; and for ≥20 cerebral microbleeds, aHR 8·61 [4·69–15·81] vs 1·86 [1·23–2·82]). However, irrespective of cerebral microbleed anatomical distribution or burden, the rate of ischaemic stroke exceeded that of intracranial haemorrhage (for ten or more cerebral microbleeds, 64 ischaemic strokes [95% CI 48–84] per 1000 patient-years vs 27 intracranial haemorrhages [17–41] per 1000 patient-years; and for ≥20 cerebral microbleeds, 73 ischaemic strokes [46–108] per 1000 patient-years vs 39 intracranial haemorrhages [21–67] per 1000 patient-years). Interpretation In patients with recent ischaemic stroke or transient ischaemic attack, cerebral microbleeds are associated with a greater relative hazard (aHR) for subsequent intracranial haemorrhage than for ischaemic stroke, but the absolute risk of ischaemic stroke is higher than that of intracranial haemorrhage, regardless of cerebral microbleed presence, antomical distribution, or burden. Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-233710 VL - 18 ER - TY - THES A1 - Christ, Thomas T1 - Value-distribution of the Riemann zeta-function and related functions near the critical line T1 - Werteverteilung der Riemannschen Zetafunktion und verwandter Funktionen nahe der kritischen Geraden N2 - The Riemann zeta-function forms a central object in multiplicative number theory; its value-distribution encodes deep arithmetic properties of the prime numbers. Here, a crucial role is assigned to the analytic behavior of the zeta-function on the so called critical line. In this thesis we study the value-distribution of the Riemann zeta-function near and on the critical line. Amongst others we focus on the following. PART I: A modified concept of universality, a-points near the critical line and a denseness conjecture attributed to Ramachandra. The critical line is a natural boundary of the Voronin-type universality property of the Riemann zeta-function. We modify Voronin's concept by adding a scaling factor to the vertical shifts that appear in Voronin's universality theorem and investigate whether this modified concept is appropriate to keep up a certain universality property of the Riemann zeta-function near and on the critical line. It turns out that it is mainly the functional equation of the Riemann zeta-function that restricts the set of functions which can be approximated by this modified concept around the critical line. Levinson showed that almost all a-points of the Riemann zeta-function lie in a certain funnel-shaped region around the critical line. We complement Levinson's result: Relying on arguments of the theory of normal families and the notion of filling discs, we detect a-points in this region which are very close to the critical line. According to a folklore conjecture (often attributed to Ramachandra) one expects that the values of the Riemann zeta-function on the critical line lie dense in the complex numbers. We show that there are certain curves which approach the critical line asymptotically and have the property that the values of the zeta-function on these curves are dense in the complex numbers. Many of our results in part I are independent of the Euler product representation of the Riemann zeta-function and apply for meromorphic functions that satisfy a Riemann-type functional equation in general. PART II: Discrete and continuous moments. The Lindelöf hypothesis deals with the growth behavior of the Riemann zeta-function on the critical line. Due to classical works by Hardy and Littlewood, the Lindelöf hypothesis can be reformulated in terms of power moments to the right of the critical line. Tanaka showed recently that the expected asymptotic formulas for these power moments are true in a certain measure-theoretical sense; roughly speaking he omits a set of Banach density zero from the path of integration of these moments. We provide a discrete and integrated version of Tanaka's result and extend it to a large class of Dirichlet series connected to the Riemann zeta-function. N2 - Die Riemannsche Zetafunktion ist ein zentraler Gegenstand der multiplikativen Zahlentheorie; in ihrer Werteverteilung liegen wichtige arithmetische Eigenschaften der Primzahlen kodiert. Besondere Bedeutung kommt hierbei dem analytischen Verhalten der Zetafunktion auf der sog. kritischen Geraden zu. Wir untersuchen in dieser Arbeit die Werteverteilung der Riemannschen Zetafunktion auf und nahe der kritischen Geraden. Wir fokusieren wir uns dabei u.a. auf folgende Punkte. TEIL I: Ein modifiziertes Universalitätskonzept, a-Stellen nahe der kritischen Geraden und eine Dichtheitsvermutung nach Ramachandra. Die kritische Gerade fungiert als natürliche Grenze für die Voroninsche Universalitätseigenschaft der Riemannschen Zetafunktion. Wir modifizieren Voronins Universalitätskonzept dahingehend, dass wir die vertikalen Translationen aus Voronins Universalitätssatz mit einer zusätzlichen Skalierung versehen. Wir untersuchen, ob durch dieses modifizierte Konzept eine abgeschwächte Universalitätseigenschaft der Riemannschen Zetafunktion um die kritschen Gerade aufrecht erhalten werden kann. Es stellt sich heraus, dass die Gestalt der Funktionen, die sich auf diese Weise durch die Zetafunktion approximieren lassen, stark von der Funktionalgleichung und der Wahl des skalierenden Faktors abhängt. Nach einem Resultat von Levinson liegen fast alle a-Stellen der Riemannschen Zetafunktion in einem trichterförmigen Bereich um die kritische Gerade. Gewisse Normalitätsargumenten sowie das Konzept der 'filling discs' erlauben uns Levinsons Resultat zu ergänzen und a-Stellen in diesem trichterförmigen Bereich aufzuspüren, die sehr nahe an der kritischen Geraden liegen. Man vermutet, dass die Werte der Riemannschen Zetafunktion auf der kritischen Geraden dicht in den komplexen Zahlen liegen. Wir nähern uns dieser Vermutung (die man oft Ramachandra zuschreibt), indem wir die Existenz gewisser Kurven nachweisen, die sich asymptotisch an die kritische Gerade anschmiegen und die Eigenschaft besitzen, dass die Werte der Zetafunktion auf diesen Kurven dicht in den komplexen Zahlen liegen. Viele unserer Ergebnisse in Teil I sind unabhängig von der Eulerproduktdarstellung der Zetafunktion und gelten allgemein für beliebige meromorphe Funktionen, die einer Funktionalgleichung vom Riemann-Typ genügen. TEIL II: Diskrete und kontinuierliche Momente. Die Lindelöf Vermutung trifft eine Aussage über das Wachstumsverhalten der Zetafunktion auf der kritischen Geraden. Nach klassischen Arbeiten von Hardy und Littlewood lässt sie sich mittels Potenzmomente der Zetafunktion rechts von der kritischen Geraden umformulieren. Tanaka konnte kürzlich nachweisen, dass die asymptotischen Formeln, die man für diese Potenzmomente erwartet in einem gewissen maßtheoretischem Sinne Gülitgkeit besitzen: grob gesprochen wird heibei eine Menge mit Banachdichte null vom Integrationsweg der Potenzmomente ausgespart. Wir stellen eine diskrete und eine integrierte Version von Tanakas Resultat zur Verfügung. Zudem verallgemeinern wir Tanakas Ergebnis auf eine große Klasse von Dirichletreihen. KW - Riemannsche Zetafunktion KW - Riemann zeta-function KW - universality KW - a-point distribution Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-97763 ER - TY - JOUR A1 - Schütz, Burkhard A1 - Jurastow, Innokentij A1 - Bader, Sandra A1 - Ringer, Cornelia A1 - Engelhardt, Jakob von A1 - Chubanov, Vladimir A1 - Gudermann, Thomas A1 - Diener, Martin A1 - Kummer, Wolfgang A1 - Krasteva-Christ, Gabriela A1 - Weihe, Eberhard T1 - Chemical coding and chemosensory properties of cholinergic brush cells in the mouse gastrointestinal and biliary tract JF - Frontiers in Physiology N2 - The mouse gastro-intestinal and biliary tract mucosal epithelia harbor choline acetyltransferase (ChAT)-positive brush cells with taste cell-like traits. With the aid of two transgenic mouse lines that express green fluorescent protein (EGFP) under the control of the ChAT promoter (EGFP\(^{ChAT}\)) and by using in situ hybridization and immunohistochemistry we found that EGFP\(^{ChAT}\) cells were clustered in the epithelium lining the gastric groove. EGFP\(^{ChAT}\) cells were numerous in the gall bladder and bile duct, and found scattered as solitary cells along the small and large intestine. While all EGFP\(^{ChAT}\) cells were also ChAT-positive, expression of the high-affinity choline transporter (ChT1) was never detected. Except for the proximal colon, EGFP\(^{ChAT}\) cells also lacked detectable expression of the vesicular acetylcholine transporter (VAChT). EGFP\(^{ChAT}\) cells were found to be separate from enteroendocrine cells, however they were all immunoreactive for cytokeratin 18 (CK18), transient receptor potential melastatin-like subtype 5 channel (TRPM5), and for cyclooxygenases 1 (COX1) and 2 (COX2). The ex vivo stimulation of colonic EGFP\(^{ChAT}\) cells with the bitter substance denatonium resulted in a strong increase in intracellular calcium, while in other epithelial cells such an increase was significantly weaker and also timely delayed. Subsequent stimulation with cycloheximide was ineffective in both cell populations. Given their chemical coding and chemosensory properties, EGFP\(^{ChAT}\) brush cells thus may have integrative functions and participate in induction of protective reflexes and inflammatory events by utilizing ACh and prostaglandins for paracrine signaling. KW - vesicular acetylcholine transporter KW - nonneuronal acetylcholine KW - nervous system KW - functional characterization KW - cholinergic KW - taste receptor cells KW - enteroendocrine cells KW - gene locus KW - tuft cells KW - transgenic mice KW - expression KW - brush cell KW - ChAT KW - VAChT KW - ChT1 KW - intestine KW - gall bladder KW - bile duct Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-143550 VL - 6 IS - 87 ER - TY - JOUR A1 - Prasse, Tobias A1 - Stratos, Ioannis A1 - Niehoff, Anja A1 - Christ, Hildegard A1 - Heck, Vincent A1 - Meyer, Carolin A1 - Mittlmeier, Thomas T1 - Bisphenol A-related effects on bone morphology and biomechanical properties in an animal model JF - Toxics N2 - Bisphenol A (BPA), which is contained in numerous plastic products, is known to act as an endocrine-disruptive, toxic, and carcinogenic chemical. This experimental series sought to determine the influence of BPA exposure on the femoral bone architecture and biomechanical properties of male and female Wistar rats. BPA was applied subcutaneously by using osmotic pumps. After 12 weeks, the bones were analyzed by micro-computed tomography (micro-CT) and a three-point bending test. Comparing the female low- and high-dose groups, a significantly greater marrow area (p = 0.047) was identified in the group exposed to a higher BPA concentration. In addition, the trabecular number tended to be higher in the female high-dose group when compared to the low-dose group (p > 0.05). The area moment of inertia also tended to be higher in the male high-dose group when compared to the male low-dose group (p > 0.05). Considering our results, BPA-related effects on the bone morphology in female Wistar rats are osteoanabolic after high-dose exposure, while, in male rats, a tendency toward negative effects on the bone morphology in terms of a reduced cross-sectional cortical area and total area could be demonstrated. KW - bisphenol A KW - endocrine disruption KW - bone morphology KW - micro-computed tomography KW - mechanical property KW - three-point bending Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-262216 SN - 2305-6304 VL - 10 IS - 2 ER -