Characterization of pericyte invasive responses and pericyte-induced vascular morphogenesis in 3D matrices : distinctions with vascular smooth muscle cells [abstract]

During vascular morphogenic events, mural cells are recruited to developing endothelial tubes to aid in stabilization and maturation of the new vessels. There are two known types of mural cells, pericytes and vascular smooth muscle cells (VSMCs). Their different locations within the vasculature (capillaries versus larger vessels, respectively) suggest that there may be distinct vessel recruitment mechanisms or factors, however, these issues remain unresolved. Platelet-derived growth factor (PDGF) is known to be released from endothelial cells during morphogenic events and has been shown to influence mural cell functions. In this study, we investigate the ability of PDGF isoforms to regulate pericyte versus VSMC invasive behaviors and recruitment to EC monolayers or developing vascular tubes

Un alga japonesa en la costa patagónica

En diciembre de 1992, a varios metros de profundidad y adheridos a los pilotes del muelle Almirante Storni de Puerto Madryn (Prov. Chubut, Argentina), se observaron algunos ejemplares de un alga de gran tamaño no registrada entre la flora marina argentina. Se trataba de Undaria pinnatifida, una especie originaria de las costas de Japón, que arribó presumiblemente en forma accidental, trasladada por barcos. Progresivamente esta especie se fue dispersando a lo largo de las costas de la Patagonia Argentina, con indeseables efectos ambientales, sociales y económicos. Se incluye información sobre las características del alga, su adaptación a diversas condiciones ambientales, su dispersión mundial, el impacto ambiental en la región, además de un glosario y lecturas sugeridas

Functional differences between pericytes and vascular smooth muscle cells during vascular morphogenesis

Title from PDF of title page (University of Missouri--Columbia, viewed on June 11, 2012).The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Thesis advisor: Dr. Michael J. DavisIncludes bibliographical references.M.S. University of Missouri-Columbia 2011."December 2011"During vascular morphogenic events, mural cells are recruited to developing endothelial tubes to aid in stabilization and maturation of the new vessels. There are two known types of mural cells, pericytes and vascular smooth muscle cells (VSMCs). Their different locations within the vasculature (capillaries versus larger vessels, respectively) suggest that different signals may be responsible for recruiting each cell type. Platelet-derived growth factor (PDGF) is released from endothelial cells (ECs) during morphogenic events and has been shown to influence mural cell functions. In this study, I investigated the ability of PDGF isoforms to regulate pericyte and VSMC invasiveness and subsequent effects on EC monolayer stability and tube sprouting. Using novel cell-invasion systems developed during this research, I show that PDGF isoforms that bind to PDGFR[beta] induce pericyte, but not VSMC invasion. Coculture studies revealed that the invasive behavior of pericytes is critical to both EC stability and sprouting. When ECs were seeded as a monolayer on top of 3D collagen gels containing pericytes, monolayer stability was enhanced compared toEC monolayers seeded alone or with VSMCs. Coculture studies also revealed that EC sprouting was sustained when pericytes were present compared to EC only cultures or EC/VSMC cocultures. Results from this work define functional differences between pericytes and VSMCs during vascular morphogenesis

The role of PDGF-BB, lysophospatidic acid, and proteolytic activity in the invasive behavior of human brain vascular pericytes [abstract]

Recruitment of pericytes is needed to stabilize new vessels formed during angiogenesis or vasculogenesis. Although important to the viability of the vessel, information on how the pericytes are recruited to blood vessels is lacking. It is believed that molecules produced by endothelial cells lining the blood vessel walls influence pericyte recruitment. Both the upward and downward invasion of human brain vascular pericytes (HBVPs) through 3D collagen gels was tested in the presence of different endothelial cell produced factors. Of the molecules tested, platelet-derived growth factor- (PDGF-BB) was found to be the most important in signaling HBVPs to invade in a 3D collagen matrix. Invasion can further be enhanced through synergism of PDGF-BB with lysophosphatidic acid (LPA), an activator of G protein signaling. When given together these two molecules increase invasion up to two times that of PDGF alone. The use of pertussis toxin, which blocks the activity of LPA, and recombinant soluble PDGF-receptor beta which traps and blocks PDGFBB, were able to significantly block invasion in response to PDGF and LPA and provide further support for their functional role in HBVP invasive behavior. Invasioncan also be blocked by using GM6001, a matrix metalloproteinase (MMP) inhibitor, demonstrating a requirement for MMP activity during this response. This work further elucidates mechanisms underlying how pericytes invade and migrate toward developing blood vessels to regulate capillary tube assembly and maturation in 3D extracellular matrix environments

Cold atoms in videotape micro-traps

We describe an array of microscopic atom traps formed by a pattern of magnetisation on a piece of videotape. We describe the way in which cold atoms are loaded into one of these micro-traps and how the trapped atom cloud is used to explore the properties of the trap. Evaporative cooling in the micro-trap down to a temperature of 1 microkelvin allows us to probe the smoothness of the trapping potential and reveals some inhomogeneity produced by the magnetic film. We discuss future prospects for atom chips based on microscopic permanent-magnet structures.Comment: Submitted for EPJD topical issue "Atom chips: manipulating atoms and molecules with microfabricated structures

On the unique possibility to increase significantly the contrast of dark resonances on D1 line of 87^{87}Rb

We propose and study, theoretically and experimentally, a new scheme of excitation of a coherent population trapping resonance for D1 line of alakli atoms with nuclear spin $I=3/2$ by bichromatic linearly polarized light ({\em lin}$||${\em lin} field) at the conditions of spectral resolution of the excited state. The unique properties of this scheme result in a high contrast of dark resonance for D1 line of $^{87}$Rb.Comment: 9 pages, 7 figures. This material has been partially presented on ICONO-2005, 14 May 2005, St. Petersburg, Russia. v2 references added; text is changed a bi

Cosmological Evolution of a Purely Conical Codimension-2 Brane World

We study the cosmological evolution of isotropic matter on an infinitely thin conical codimension-two brane-world. Our analysis is based on the boundary dynamics of a six-dimensional model in the presence of an induced gravity term on the brane and a Gauss-Bonnet term in the bulk. With the assumption that the bulk contains only a cosmological constant Lambda_B, we find that the isotropic evolution of the brane-universe imposes a tuned relation between the energy density and the brane equation of state. The evolution of the system has fixed points (attractors), which correspond to a final state of radiation for Lambda_B=0 and to de Sitter state for Lambda_B>0. Furthermore, considering anisotropic matter on the brane, the tuning of the parameters is lifted, and new regions of the parametric space are available for the cosmological evolution of the brane-universe. The analysis of the dynamics of the system shows that, the isotropic fixed points remain attractors of the system, and for values of Lambda_B which give acceptable cosmological evolution of the equation of state, the line of isotropic tuning is a very weak attractor. The initial conditions, in this case, need to be fine tuned to have an evolution with acceptably small anisotropy.Comment: 20 pages, 4 figures, typo correcte

Current research, pressing issues, and lingering questions in marine invasion science: lessons from the Tenth International Conference on Marine Bioinvasions (ICMB-X)

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Fowler, A. E., Blakeslee, A. M. H., Bortolus, A., Dias, J., Tepolt, C. K., & Schwindt, E. Current research, pressing issues, and lingering questions in marine invasion science: lessons from the Tenth International Conference on Marine Bioinvasions (ICMB-X). Aquatic Invasions, 15(1), (2020): 1-10, doi:10.3391/ai.2020.15.1.01.Research on marine bioinvasions is an inherently international collaboration. Species range boundaries have become more fluid in recent decades as a result of enhanced human globalization, leading to species translocations across international boundaries through high profile vectors (e.g., shipping, hull fouling, aquaculture, etc.) (Ruiz et al. 2000; Seebens et al. 2013). Global trade and anthropogenic activities that promote invasive species spread continue to increase, rising by an average of 70% since 1970, with no sign of saturation (Pagad et al. 2015; Seebens et al. 2017). Even though these numbers are primarily based on terrestrial systems, recent work has demonstrated that marine ecosystems are as severely impacted by invasive species as by other human activities including overfishing, pollution (including plastics), climate change, and ocean acidification (Diaz et al. 2019). Species introductions to seas, coasts, and estuaries are therefore a global threat to human and non-human populations alike. As such, scientists and managers are increasingly focused on prevention and management, risk analysis and prioritization, and innovative technologies to detect novel species.The ICMB-X was supported by CONICET, MINCyT, SCTeIP Chubut, Consejo Federal de Inversiones, Biodiversity Heritage Library, Administración Portuaria de Puerto Madryn (APPM), Office of Naval Research Global, Aluar Aluminio Argentino, Madryn Bureau, Ente Mixto Puerto Madryn, Municipalidad de Puerto Madryn, and FAO-GEF-SAyDS

Versorgung und Reanimation des reifen Neugeborenen nach der Geburt : Basierend auf der aktuellen Leitlinie des European Resuscitation Council 2021

Zusammenfassung Die volle Reanimation eines Neugeborenen mit Beatmungen, Thoraxkompressionen und der Gabe von Medikamenten ist ein äußerst seltenes Ereignis, das selbst neonatologische Teams immer wieder vor Herausforderungen stellt. Gerade in diesen seltenen und häufig dramatischen Situationen ist schnelles und umsichtiges Handeln im Team gefragt. Dabei ist die effektivste und meist einzig notwendige Maßnahme für die erfolgreiche Versorgung eines nicht spontan atmenden Neugeborenen eine suffiziente Maskenbeatmung. Wird diese effektiv durchgeführt, sind beim Neugeborenen in den seltensten Fällen tatsächlich Thoraxkompressionen notwendig. Im März 2021 wurde vom European Resuscitation Council (ERC) die neue Leitlinie zur Reanimation von Neugeborenen publiziert. Auf Basis dieser Leitlinie beschreibt der vorliegende Beitrag detailliert den im Algorithmus der Versorgung und Reanimation von reifen Neugeborenen dargestellten Handlungsablauf. Er richtet sich damit einerseits insbesondere an NichtneonatologInnen, die für die Versorgung v. a. von reifen Neugeborenen nach der Geburt verantwortlich sind. Andererseits soll er auch jenen zur Unterstützung dienen, die medizinisches Personal in der Versorgung von lebensbedrohten Neugeborenen trainieren und den Algorithmus der Neugeborenenreanimation als didaktisches Konzept vermitteln. Abstract The resuscitation of a neonate with the need for ventilation, chest compressions and the administration of drugs is an extremely rare event that repeatedly challenges even neonatal teams. It is precisely in these rare and often dramatic situations that rapid and prudent team action is required. The most effective and usually the only necessary measure for the successful resuscitation of a neonate who is not breathing spontaneously is sufficient mask ventilation. If ventilation is performed effectively, chest compressions are rarely necessary in the neonate. In March 2021, the European Resuscitation Council (ERC) published the new guidelines for neonatal resuscitation. Based on these guidelines, this article describes in detail the course of action outlined in the algorithm for the stabilisation and resuscitation of term neonates. On the one hand, it is aimed at non-neonatologists who are responsible for the care of term neonates after birth. On the other hand, it is also intended to support those who train medical personnel in the care of life-threatened neonates and teach the algorithm of neonatal resuscitation as a didactic concept