9 research outputs found
Generation of human colon organoids from healthy and inflammatory bowel disease mucosa
Ulcerative colitis and Crohn's disease are chronic inflammatory bowel diseases (IBD) of unknown cause characterized by a relapsing-remitting behavior. Growing evidence supports the idea that the epithelial barrier plays a central role in the pathogenesis of IBD as well as in its evolution over time, thus representing a potential target for novel therapeutic options. In the last decade, the introduction of 3D epithelial cultures from ex vivo-expanded intestinal adult stem cells (ASCs) has impacted our ability to study the function of the epithelium in several gastrointestinal disorders, including IBD. Here, we describe in detail a reproducible protocol to generate Matrigel-embedded epithelial organoids from ASCs of non-IBD and IBD donors using small colonic biopsies, including steps for its optimization. A slightly modified version of this protocol is also provided in case surgical samples are used. With this method, epithelial organoids can be expanded over several passages, thereby generating a large quantity of viable cells that can be used in multiple downstream analyses including genetic, transcriptional, proteomic and/or functional studies. In addition, 3D cultures generated using our protocol are suitable for the establishment of 2D cultures, which can model relevant cell-to-cell interactions that occur in IBD mucosa
Faraday rotation and transmittance as markers of topological phase transitions in 2D materials
We analyze the magneto-optical conductivity (and related magnitudes like
transmittance and Faraday rotation of the irradiated polarized light) of some
elemental two-dimensional Dirac materials of group IV (graphene analogues,
buckled honeycomb lattices, like silicene, germanene, stannane, etc.), group V
(phosphorene), and zincblende heterostructures (like HgTe/CdTe quantum wells)
near the Dirac and gamma points, under out-of-plane magnetic and electric
fields, to characterize topological-band insulator phase transitions and their
critical points. We provide plots of the Faraday angle and transmittance as a
function of the polarized light frequency, for different external electric and
magnetic fields, chemical potential, HgTe layer thickness and temperature, to
tune the material magneto-optical properties. We have shown that
absortance/transmittance acquires extremal values at the critical point, where
the Faraday angle changes sign, thus providing fine markers of the topological
phase transition.Comment: 15 pages, 11 figures, including supplemental material with 5 pages
and 4 figures, 3 animated gif
Faraday rotation and transmittance as markers of topological phase transitions in 2D materials
We analyze the magneto-optical conductivity (and related magnitudes like transmittance
and Faraday rotation of the irradiated polarized light) of some elemental twodimensional
Dirac materials of group IV (graphene analogues, buckled honeycomb lattices,
like silicene, germanene, stannane, etc.), group V (phosphorene), and zincblende
heterostructures (like HgTe/CdTe quantum wells) near the Dirac and gamma points, under
out-of-plane magnetic and electric fields, to characterize topological-band insulator
phase transitions and their critical points. We provide plots of the Faraday angle and
transmittance as a function of the polarized light frequency, for different external electric
and magnetic fields, chemical potential, HgTe layer thickness and temperature, to tune
the material magneto-optical properties. We have shown that absortance/transmittance
acquires extremal values at the critical point, where the Faraday angle changes sign, thus
providing fine markers of the topological phase transition. In the case of non-topological
materials as phosphorene, a minimum of the transmittance is also observed due to the
energy gap closing by an external electric field.Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucía (through Organization: Consejería de Economía Innovación Ciencia y Empleo)Ministerio de Ciencia e InnovaciónUniversidad Nacional Autónoma de México / National Autonomous University of Mexico [UNAM
The host galaxies of luminous type 2 AGNs at z ~ 0.3-0.4
We study the morphological and structural properties of the host galaxies associated with 57 optically selected luminous type 2 active galactic nuclei (AGNs) at z ∼ 0.3–0.4: 16 high-luminosity Seyfert 2 [HLSy2, 8.0 ≤ log(L[OIII]/L⊙)< 8.3] and 41 obscured [QSO2, log(L[OIII]/L⊙)≥ 8.3] quasars. With this work, the total number of QSO2s at z < 1 with parametrized galaxies increases from ∼35 to 76. Our analysis is based on Hubble Space Telescope WFPC2 and ACS images that we fit with GALFIT. HLSy2s and QSO2s show a wide diversity of galaxy hosts. The main difference lies in the higher incidence of highly disturbed systems among QSO2s. This is consistent with a scenario in which galaxy interactions are the dominant mechanism triggering nuclear activity at the highest AGN power. There is a strong dependence of galaxy properties with AGN power (assuming L[OIII] is an adequate proxy). The relative contribution of the spheroidal component to the total galaxy light (B/T) increases with L[OIII]. While systems dominated by the spheroidal component spread across the total range of L[OIII], most disc-dominated galaxies concentrate at log(L[OIII]/L⊙)<8.6. This is expected if more powerful AGNs are powered by more massive black holes which are hosted by more massive bulges or spheroids. The average galaxy sizes (〈re〉) are 5.0 ± 1.5 kpc for HLSy2s and 3.9 ± 0.6 kpc for HLSy2s and QSO2s, respectively. These are significantly smaller than those found for QSO1s and narrow-line radio galaxies at similar z. We put the results of our work in the context of related studies of AGNs with quasar-like luminosities.JUM and MVM acknowledge support from the Spanish former Ministerio de Economía y Competitividad through the grants AYA2012-32295 and AYA2015-64346-C2-2-P. FB acknowledges the support by FCT via the postdoctoral fellowship SFRH/BPD/103958/2014. This work is supported by Fundacao para a Ciencia e a Tecnologia (FCT) through national funds (UID/FIS/04434/2013) and by FEDER through COMPETE2020 (POCI-01-0145-FEDER-007672). FB also acknowledges support from grant AYA2016-77237-C3-1-P from the Spanish Ministry of Economy and Competitiveness (MINECO). JPL acknowledges support from the Spanish Ministerio de Economía y Competitividad through the grant AYA2017-85170-R. BRP acknowledges financial support from the Spanish Ministry of Economy and Competitiveness through grant ESP2015-68964. F.J.C. acknowledges financial support through grant AYA2015-64346-C2-1-P (MINECO/FEDER)
The host galaxies of luminous type 2 AGNs at z ∼ 0.3–0.4
ABSTRACT: We study the morphological and structural properties of the host galaxies associated with 57 optically selected luminous type 2 active galactic nuclei (AGNs) at z ∼ 0.3–0.4: 16 high-luminosity Seyfert 2 [HLSy2, 8.0 ≤ log(L[oIII]/Lʘ) < 8.3] and 41 obscured [QSO2, log(L[O III]/Lʘ) ≥ 8.3] quasars. With this work, the total number of QSO2s at z < 1 with parametrized galaxies increases from ∼35 to 76. Our analysis is based on Hubble Space Telescope WFPC2 and ACS images that we fit with GALFIT. HLSy2s and QSO2s show a wide diversity of galaxy hosts. The main difference lies in the higher incidence of highly disturbed systems among QSO2s. This is consistent with a scenario in which galaxy interactions are the dominant mechanism triggering nuclear activity at the highest AGN power. There is a strong dependence of galaxy properties with AGN power (assuming L[O III] is an adequate proxy). The relative contribution of the spheroidal component to the total galaxy light (B/T) increases with L[O III]. While systems dominated by the spheroidal component spread across the total range of L[O III], most disc-dominated galaxies concentrate at log(L[O III]/Lʘ)JUM and MVM acknowledge support from the Spanish former Ministerio de Economía y Competitividad through the grants AYA2012-32295 and AYA2015-64346-C2-2-P. FB also acknowledges support from grant AYA2016-77237-C3-1-P from the Spanish Ministry of Economy and Competitiveness (MINECO). JPL
acknowledges support from the Spanish Ministerio de Economía y Competitividad through the grant AYA2017-85170-R. BRP acknowledges financial support from the Spanish Ministry of Economy and Competitiveness through grant ESP2015-68964. F.J.C. acknowledges financial support through grant AYA2015-64346-C2-1-P (MINECO/FEDER)
Requisits higienicosanitaris en l’elaboració de formatges a partir de llet crua
Control oficial; Formatges; Llet crua; APPCCControl oficial; Quesos; Leche cruda; APPCCOfficial control; Cheeses; Raw milk; HACCPL’objectiu d’aquesta Comunitat de Pràctica (CoP ) és recollir uns criteris i elaborar un document de requisits sanitaris que cal seguir en la gestió del risc de l’elaboració dels formatges fets amb llet crua amb un període de maduració inferior a 60 dies.
Els operadors econòmics han de garantir la seguretat dels seus productes i han d’aplicar programes d’autocontrol en matèria de seguretat alimentària, basats en l’anàlisi de perills i punts de control crític (APPCC), per garantir la innocuïtat dels seus productes. Les autoritats sanitàries són responsables de vetllar, mitjançant la vigilància i el control oficials, perquè aquests productes respectin les normes de seguretat alimentària.
En el cas dels formatges elaborats amb llet crua, se’ns plantegen diversos problemes respecte a la seguretat alimentària, i comprovem que, cada cop més, els petits productors elaboren formatges amb llet crua amb períodes de maduració inferiors als 60 dies, que després són venuts en fires, mercats locals o altres establiments alimentaris i fins i tot exportats. El marc normatiu (Reglament (CE) 853/2004)1 recull l’elaboració d’aquests tipus de formatges sempre que es reuneixin uns requisits sanitaris específics, cosa que fins que no va entrar en vigor havia estat prohibida per la normativa espanyola (Reial decret 1679/1994).
Atesa la complexitat i el risc que aquests productes poden suposar, tant els inspectors de l’ASPCAT com els inspectors de l’àmbit local es preocupen pels criteris tecnològics i d’autocontrols microbiològics que s’han de complir en aquests establiments per garantir la seguretat alimentària.El objetivo de esta Comunidad de Práctica (CoP) es recoger unos criterios y elaborar un documento de requisitos sanitarios a seguir en la gestión del riesgo de la elaboración de los quesos hechos con leche cruda con un período de maduración inferior a 60 días .
Los operadores económicos deben garantizar la seguridad de sus productos y deben aplicar programas de autocontrol en materia de seguridad alimentaria, basados en el análisis de peligros y puntos de control crítico (APPCC), para garantizar la inocuidad de sus productos. Las autoridades sanitarias son responsables de velar, mediante la vigilancia y control oficiales, para que estos productos respeten las normas de seguridad alimentaria.
En el caso de los quesos elaborados con leche cruda, se nos plantean varios problemas respecto a la seguridad alimentaria, y comprobamos que, cada vez más, los pequeños productores elaboran quesos con leche cruda con períodos de maduración inferiores a los 60 días, que después son vendidos en ferias, mercados locales u otros establecimientos alimenticios e incluso exportados. El marco normativo (Reglamento (CE) 853/2004)1 recoge la elaboración de este tipo de quesos siempre que se reúnan unos requisitos sanitarios específicos, algo que hasta que no entró en vigor había sido prohibido por la normativa española (Real decreto 1679/1994).
Dada la complejidad y el riesgo que estos productos pueden suponer, tanto los inspectores de la ASPCAT como los inspectores del ámbito local se preocupan por los criterios tecnológicos y de autocontroles microbiológicos que deben cumplirse en estos establecimientos para garantizar la seguridad alimentaria.The objective of this Community of Practice (CoP) is to collect criteria and prepare a document of health requirements to be followed in the management of the risk of the production of cheeses made with raw milk with a maturation period of less than 60 days.
Economic operators must guarantee the safety of their products and must apply self-control programs regarding food safety, based on hazard analysis and critical control points (HACCP), to guarantee the safety of their products. Health authorities are responsible for ensuring, through official surveillance and control, that these products respect food safety standards.
In the case of cheeses made with raw milk, we face several problems regarding food safety, and we see that, increasingly, small producers make cheeses with raw milk with maturation periods of less than 60 days, which then They are sold at fairs, local markets or other food establishments and even exported. The regulatory framework (Regulation (EC) 853/2004)1 includes the production of this type of cheese as long as specific health requirements are met, something that until it came into force had been prohibited by Spanish regulations (RD 1679/1994).
Given the complexity and risk that these products can pose, both ASPCAT inspectors and local inspectors are concerned about the technological and microbiological self-control criteria that must be met in these establishments to guarantee food safety
Sensibilidad a los antimicrobianos de Enterococcus faecalis aislados de pacientes en la provincia de Córdoba (España)
Enterococcus faecalis es un microorganismo patógeno para el hombre. El objetivo de este estudio fue conocer la sensibilidad a diferentes antibióticos de los aislamientos obtenidos en la provincia de Córdoba en un periodo de 20 meses, de enero de 2004 a agosto de 2005. Los porcentajes de sensibilidad para los betalatámicos fueron del 98% a ampicilina y del 99% a amoxicilina-ácido clavulánico. Los aminoglucósidos estreptomicina y gentamicina, probados a altas dosis (estreptomicina 1000 µg y gentamicina 500 µg), obtuvieron un porcentaje de sensibilidad del 56% y el 76%, respectivamente. No se encontró ninguna cepa resistente a glucopéptidos (vancomicina y teicoplanina) ni a linezolid