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A 3D Bioprinted Gut Anaerobic Model for Studying Bacteria–Host Interactions

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Research 2023年第3期6卷 697-710页

作者： Liqin Cheng Tingting Liu Qiong Liu Liming Lian Guosheng Tang Luis santiago Mille Fabricio Romero García Lars Engstrand Yu Shrike Zhang Juan Du Centre for Translational Microbiome Research(CTMR) Department of MicrobiologyTumorand Cell BiologyKarolinska InstitutetStockholmSweden Division of Engineering in Medicine Department of MedicineBrigham and Women’s HospitalHarvard Medical School65 Landsdowne StreetCambridgeMA 02139USA Science for Life Laboratory StockholmSweden

The role of the human intestinal tract in host–microbe interactions has been highlighted in recent *** 3-dimensional(3D)models have been developed to reproduce the physiological characteristics of the human gut and to investigate the function of the gut *** challenge for 3D models is to recapitulate the low oxygen concentrations in the intestinal ***,most earlier 3D culture systems used a membrane to physically separate bacteria from the intestinal epithelium,which has sometimes made the studies of bacteria adhering to or invading cells less *** report the establishment of a 3D gut epithelium model and cultured it at high cell viability under an anaerobic *** further cocultured intestinal bacteria including both commensal and pathogen directly with epithelial cells in the established 3D model under the anaerobic *** subsequently compared the gene expression differences of aerobic and anaerobic conditions for cell and bacterial growth via dual RNA *** study provides a physiologically relevant 3D gut epithelium model that mimics the anaerobic condition in the intestinal lumen and supplies a powerful system for future in-depth gut–microbe interactional investigations.

关键词： epithelium Host Bacteria

Safety of tirofiban and dual antiplatelet therapy in treating intracranial aneurysms

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Stroke & Vascular Neurology 2019年第1期4卷 36-42页

作者： Edgar A Samaniego Emilee Gibson Daichi Nakagawa santiago Ortega-Gutierrez Mario Zanaty Jorge A Roa Pascal Jabbour David M Hasan Department of Neurology Neurosurgery and RadiologyUniversity of Iowa Hospitals and ClinicsIowa CityIowaUSA Department of Neurology University of Iowa Hospitals and ClinicsIowa CityIowaUSA Department of Neurosurgery University of Iowa Hospitals and ClinicsIowa CityIowaUSA Department of Neurosurgery Thomas Jefferson UniversityPhiladelphiaPennsylvaniaUSA

Background Endovascular treatment of intracranial aneurysms usually involves stent-assisted coiling(SAC)and flow *** IIb/IIIa inhibitors such as tirofiban and dual antiplatelet therapy(DAPT)are required to prevent thromboembolic complications *** sought to determine the safety of tirofiban and DAPT in these *** We conducted a retrospective analysis of our database for patients with intracranial aneurysms who underwent SAC or flow *** tirofiban-DAPT protocol used is *** regarding duration of infusion,placement of external ventricular devices(EVDs),complications,haemoglobin levels and platelet count before and 24 hours after antiplatelet therapy were collected and *** One-hundred and forty-one patients with 148 aneurysms/procedures were included.110 aneurysms were treated acutely and 38 *** and major haemorrhagic events were recognised in 20%(30/148)*** 5(3.4%)intracerebral haemorrhages were symptomatic:3 cortical/SAH and 2 *** average blood volume in symptomatic haemorrhages was 24.8 cc versus 5.42 cc in asymptomatic haemorrhages(p=0.002).The rate of EVD-related haemorrhages was 15.7%(19/121)and only 2(1.7%)were *** haemorrhagic events occurred in ruptured aneurysms(90.1%,p=0.01).No significant change in platelet count or haemoglobin levels before and 24 hours after administration of tirofiban and DAPT was *** administration of heparin did not increase haemorrhagic *** The use of the GP IIb/IIIa inhibitors tirofiban and DAPT in this series was *** and DAPT did not affect platelet count or haemoglobin levels and did not increase rate of symptomatic haemorrhages or thromboembolic complications.

关键词： aneurysm intracranial infusion

Preparation and Characterization of Flexible, Transparent and Thermally Stable Aromatic Co-polyamides

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Chinese Journal of Polymer Science 2019年第2期37卷 136-141页

作者： José Antonio Tec-Sánchez Andrés Iván Oliva Arias Manuel Aguilar-Vega Juan Valerio Cauich-Rodríguez José Luis santiago-García Unidad de Materiales Centro de Investigación Científica de Yucatán A. C. Centro de Investigación y de Estudios Avanzados del IPN Unidad Mérida Departamento de Física Aplicada

Two aromatic co-polyamides were synthesized combining two diacid monomers containing bulky pendant groups, 5-(9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboximido)isophthalic acid(DEAIA) and 5-tert-butylisophthalic acid(TERT), with 4,4′-(hexafluoroisopropylidene)dianiline(HFA) or 2,3,5,6-tetramethyl-1,4-phenylenediamine(Durene) by direct polycondensation. The structures of the obtained aromatic co-polyamides were confirmed by FTIR, Raman and 1 H-NMR. The co-copolyamide films, DHTH and DDTD, exhibited rms-roughness values between 0.94 and 1.60 nm, respectively. Moreover, they presented good thermal stability up to300 °C. Young's moduli of the co-polyamide films were between 4.1 and 4.3 GPa. X-ray diffraction results showed that the co-polyamide films were amorphous due to the incorporation of both bulky pendant groups, tert-butyl and dibenzobarrelene. The combination of bulky pendant groups provided intrinsically transparent co-polyamide films with a transmittance higher than 88% in the range of 400-780 *** to these outstanding film and optical properties, they are suggested to be flexible substrates in applications for solar cell and other portable electronic devices.

关键词： Co-polyamides Flexible films Transmittance Thermal stability Polycondensation

Structural studies of BaTiO_3:Er^(3+) and BaTiO_3:Yb^(3+) powders synthesized by hydrothermal method

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Journal of Rare Earths 2014年第11期32卷 1016-1021页

作者： Garrido-Hernández A García-Murillo A Carrillo-Romo F de J Cruz-santiago L A Chadeyron G Morales-Ramírez A de J Velumani S T.A. Post-graduate Student. Instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F México Instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F Departament of Engineering Materials Tecnológico de Estudios Superiores de Coacalco (TESCo) Av. 16 de Septiembre # 54 Cabecera Municipal C.P. 55700 Coacalco de Berriozábal Estado de México Institut de Chimie de Clermont-Ferrand UMR 6296 CNRS / UBP / ENSCCF 24 avenue des Landais BP 80026 63171 Aubière Cedex – France Department of Electrical Engineering (SEES) Centro de Investigación y de Estudios Avanzados del IPN Av. Instituto Politécnico Nacional 2508 Col. San Pedro Zacatenco C.P. 07360 Mexico D.F. Mexico

Erbium and ytterbium doped barium titanate nanopowders were prepared using the hydrothermal method. A barium titanate structure doped with rare earth ions manifested new characteristics and improved the field of application of optical devices such as trichromatic tubes, LCD displays, lamps, and infrared lasers. In this work, BaTiO3：Er3＋ and BaTiO3：Yb3＋ were prepared using barium chloride [BaCl2], titanium butoxide [C16H36O4Ti], erbium chloride [ErCl3] and ytterbium chloride [YbCl3] as precursors. Anhydrous methanol was employed as a solvent. Metallic potassium was used to promote solubility in the system and increase the pH to 13. This method yielded the formation of a predominantly cubic structure in both Er3＋ and Yb3＋ doped BaTiO3 powders. Characteristic bondings of BaTiO3 were observed with FT-IR spectroscopy. The predominantly cubic structure was confirmed by X-ray diffraction and micro-Raman analyses. The particle size（～30 nm） was estimated using the Scherrer equation and X-ray diffraction data. The results were presented and discussed.

关键词： nanopowders hydrothermal BaTiO3:Er3+ BaTiO3:Yb3+ rare earths

PM Diagram of the Transfer Function and Its Use in the Design of Controllers

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Journal of Mathematics and System Science 2015年第4期5卷 138-149页

作者： santiago Garrido Luis Moreno Carlos Ⅲ University of Madrid Spain

This paper presents an enhanced Root Locus diagram that consists of the representation of the phase and the magnitude of the transfer function G（s） of a system. The magnitude is represented in decibels and the phase is represented by colors. It also presents how to use it to calculate different kinds of controllers. An important characteristic of this diagram is that permits to read the phase and the gain margins directly and the imaginary axis cut represents the Bode diagram. It is also possible to put the grid with damping ratio ξ and frequency ωn.

关键词： Root Locus PID controller Lead network Bode plot Phase margin Gain margin.

Population structuring of the ubiquitous stingless bee Tetragonisca angustula in southern Brazil as revealed by microsatellite and mitochondrial markers

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Insect Science 2017年第5期24卷 877-890页

作者： Flavio O. Francisco Leandro R. santiago Yuri M. Mizusawa Benjamin P. Oldroyd Maria C. Arias Departamento de Genetica e Biologia Evolutiva Instituto de Biociencias Universidade de Sao Paulo Rua do MatZo 277 - sala 320Sao Paulo SP Brazi Behaviour and Genetics of Social Insects Lab School of Life and Environmental Sciences A 12 University of Sydney Sydney NSW Australia

Tetragonisca angustula is one of the most widespread stingless bees in the Neotropics. This species swarms frequently and is extremely successful in urban envi- ronments. In addition, it is one of the most popular stingless bee species for beekeeping in Latin America, so nest transportation and trading is common. Nest transportation can change the genetic structure of the host population, reducing inbreeding and increasing homogenization. Here, we evaluate the genetic structure of 17 geographic populations of T. angustula in southern Brazil to quantify the level of genetic differentiation between populations. Analyses were conducted on partially sequenced mitochondrial genes and 11 microsatellite loci of 1002 workers from 457 sites distributed on the mainland and on 3 islands. Our results show that T. angustula populations are highly differentiated as demon- strated by mitochondrial DNA （mtDNA） and microsatellite markers. Of 73 haplotypes, 67 were population-specific. MtDNA diversity was low in 9 populations but microsatellite diversity was moderate to high in all populations. Microsatellite data suggest 10 genetic clusters and low level of gene flow throughout the studied area. However, physical barri- ers, such as rivers and mountain ranges, or the presence or absence of forest appear to be unrelated to population clusters. Factors such as low dispersal, different ecological con- ditions, and isolation by distance are most likely shaping the population structure of this species. Thus far, nest transportation has not influenced the general population structure in the studied area. However, due to the genetic structure we found, we recommend that nest transportation should only occur within and between populations that are genetically similar.

关键词： genetic structure islands Meliponini microsatellites mtDNA nest transportation

Early life investment in antlers and body growth reflects adult performance in roe deer population under supplementary feeding conditions

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Integrative Zoology 2022年第3期17卷 396-407页

作者： Marta PELÁEZ Isabel SANUY Juan Carlos PERAL JoséLuisÁlvarez ESTEBAN santiago LAVÍN Emmanuel SERRANO Ramón PEREA Departamento de Sistemas y Recursos Naturales Universidad Politécnica de MadridMadridSpain Wildlife Ecology&Health group(WE&H)and Servei d’Ecopatologia de Fauna Salvatge(SEFaS).Facultat de Veterinària Universitat Autònoma de Barcelona(UAB)BarcelonaSpain Centro Cinegético I+D de Valsemana Junta de Castilla y LeónLa ErcinaLeónSpain

Recent research has challenged the idea that cervid antlers are such costly traits,supporting the assertion early-life antler investment is an honest signal of adult phenotypic ***,inferences were made based on antler measurements while growing(velvet)and thus,studies on fully-formed clean antlers are needed to avoid possible bias caused by the inter-individual variation in antler growth *** studied a semi-captive population of European roe deer inhabiting a sub-Mediterranean area(Valsemana research station)and living under optimal conditions(ad libitum food supply and veterinary care).Based on repeated measurements taken from 146 individuals,we assessed whether allocation to secondary sexual traits during early life affected body mass or antler development during ***,we evaluated which body measurements better predicted future male ***,using 488 individuals,we described age-class-specific variation in male body measurements and assessed the decline in antler size between adult and senescent stages(*** of senescence).Results agree with the assertion that there is no negative effect of a high investment in antler during early life on adult antler size or body mass,but we suggest the use of clean antlers as a more robust and reliable *** variables that better predicted body mass during adulthood were yearling body mass and body size at 6 *** score between 10 and 18 months resulted in the best indicator of adult antler ***,we support the idea that the magnitude of senescence in antler size is smaller in environments with higher resource availability during winter.

关键词： antler size body mass early-life investment Mediterranean environments secondary sexual traits and senescence trade-offs

Opposed elevational variation in prevalence and intensity of endoparasites and their vectors in a lizard

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Current Zoology 2018年第2期64卷 197-204页

作者： Lola ALVAREZ-RUIZ Rodrigo MEGIA-PALMA Senda REGUERA santiago Rulz Francisco J. ZAMORA-CAMACHO Jordi FIGUEROLA Gregorio MORENO-RUEDA Centro de Investigaciones sobre Desertificacion-CSIC Ctra. Naquera Kin. 4.5 Moncada Valencia E-46113 Spain Departarnento de Ecologia Evolutiva Museo Nacional de Ciencias Naturales-CSIC c/Jose Gutierrez Abascal Madrid E-28006 Spain Unit of Ethology and Animal Welfare Faculty of Veterinary University CEU Cardenal Herrera Alfara del Patriarca (Valencia) E-46113 Spain Servicio de Control de Mosquitos DiputaciGn Provincial de Huelva Centro de InvestigaciGn Biornedica en Red Epidemiologia y Salud Publica (CIBERESP) Huelva Spain CIBER de Epidemiologia y Salud Peblica (CIBERESP) Spain Departamento de Biogeografia y Carnbio Global Museo Nacional de Ciencias Naturales-CSIC C/Jose Gutierrez Abascal 2 Madrid E-28006 Spain Departarnento de Ecologia de Hurnedales Estacion Biologica de Dofiana-CSIC c/Americo Vespucio s/n Sevilla E-41092 Spain Departamento de Zoologia Facultad de Ciencias Universidad de Granada Granada E-18071 Spain

Studying the causes of parasite geographic distribution is relevant to understand ecological and evolutionary processes that affect host populations as well as for species conservation. Temperature is one of the most important environmental variables affecting parasite distribution, as raising temperatures positively affect development, reproduction, and rate of transmission of both endo- and ectoparasites. In this context, it is generally accepted that, in mountains, parasite abundance decreases with elevation. However, empirical evidence on this topic is limited. In the present study, we analyzed the elevational variation of hemoparasites and ectoparasites of a lizard, Psammodromus algirus, along a 2,200-m elevational gradient in Sierra Nevada （SE Spain）. As pre- dicted, ectoparasite （mites, ticks, mosquitoes, and sandflies） abundance decreased with elevation. However, hemoparasite prevalence and intensity in the lizard augmented with altitude, showing a pattern contrary to their vectors （mites）. We suggest that tolerance to hemoparasites may increase with elevation as a consequence of lizards at high altitudes taking advantage of increased body condition and food availability, and reduced oxidative stress. Moreover, lizards could have been selected for higher resistance against hemoparasites at lowlands （where higher rates of replication are expected）, thus reducing hemoparasite prevalence and load. Our findings imply that, in a scen- ario of climate warming, populations of lizards at high elevation may face increased abundance of ectoparasites, accompanied with strong negative effects.

关键词： elevation immune system parasite distribution Psammodromus algirus reptile

Is the Space-Time a Superconductor?

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Journal of Modern Physics 2013年第10期4卷 1447-1467页

作者： Wenceslao santiago-Germán Manuel Sandoval Vallarta Institute for Theoretical Physics Chetumal México

At the fundamental level, the 4-dimensional space-time of our direct experience might not be a continuum and discrete quantum entities might “collectively” rule its dynamics. Henceforth, it seems natural to think that in the “low-energy” regime some of its distinctive quantum attributes could, in principle, manifest themselves even at macroscopically large scales. Indeed, when confronted with Nature, classical gravitational dynamics of spinning astrophysical bodies is known to lead to paradoxes: to untangle them, dark matter or modifications to the classical law of gravity are openly considered. In this article, the hypothesis of a fluctuating space-time acquiring “at large distances” the properties of a Bose-Einstein condensate is pushed forward: firstly, it is shown that a natural outcome of this picture is the production of monopoles, dyons, and vortex lines of “quantized” gravitomagnetic—or gyrogravitational—flux along the transition phase;the minimal supported “charge” (and multiples of it) being directly linked with a nonzero (minimal) vacuum energy. Thus, a world of vibrating, spinning, interacting strings whose only elements in their construction are our topological concepts of space and time is envisioned, and they are proposed as tracers of the superfluid features of the space-time: the archetypal embodiment of these physical processes being set by the “gravitational roton”, an analogue of Landau’s classic higher-energy excitation used to explain the superfluid properties of helium II. The far and the near field asymptotics of string line solutions are presented and used to deduce their pair-interaction energy. Remarkably, it is found that two stationary, axis-aligned, quantum space-time vortices with the same sense of spin not only exhibit zones of repulsion but also of attraction, depending on their relative geodetic distance.

关键词： Modified Gravity Superconductivity Kinematics Dynamics Rotation