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Polycaprolactone-carboxymethyl cellulose composites for manufacturing porous scaffolds by material extrusion

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Bio-Design and Manufacturing 2018年第4期1卷 245-253页

作者： M.E.Aleman-Domfnguez Z.ortega A.N.Benitez Mario monzon L.V.Garzon Sara Ajami Chaozong Liu Departamento de Ingenier/a de Procesos Universidad de Las Palmas de Gran CanadaEdificio de Fabricacion integrada Parque Cientifico-Tecnologico de la ULPGC35017Las PalmasSpain Departamento de Ingenierfa Mecainica Universidad de Las Palmas de Gran CanadaEdificio de Fabricacion integrada Parque Cientifico-Tecnologico de la ULPGC35017 Las PalmasSpain Institute of Orthopaedic and Musculoskeletal Science Royal National Orthopaedic HospitalUniversity College London StanmoreLondon HA74LPUK

Polycaprolactone-carboxymethyl cellulose composites have been obtained and used to print porous structures by material *** materials used contained 0,2 and 5% w/w of the carboxymethyl cellulose *** structures have been analyzed in terms of their morphology (including the evaluation of their porosity),mechanical properties under compression load and cell *** affinity has been evaluated by culturing sheep mesenchymal stem cells and analyzing their viability by the Alamar Blue(R)assay at days 1,3,6 and *** results show that composites samples have similar values of porosity and apparent density than pure polycaprolactone ***,samples containing 5%w/w of carboxymethyl cellulose have micropores on the filaments due to a hindered deposition *** characteristic affects the mechanical properties of the structures,so these ones have a mean compression modulus significantly lower than pure polycaprolactone ***, the samples containing 2%w/w of carboxymethyl cellulose show no significant difference with the pure polycaprolactone ones in terms of their mechanical ***,the presence of 2%w/w of additive improves cell proliferation on the surface of the porous *** complementary information,the flow properties of the composite materials were studied and the power law equations at 210℃ obtained,as this temperature was the 3D printing *** equations can be useful for simulation and designing purposes of other manufacturing processes.

关键词： Additive manufacturing Tissue engineering Viscosity model Biomaterials 3D printing Bone regeneration

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Stroke mechanisms and outcomes of isolated symptomatic basilar artery stenosis

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Stroke & Vascular Neurology 2019年第4期4卷 189-197页

作者： Edgar A Samaniego Amir Shaban Santiago ortega-Gutierrez Jorge A Roa David M Hasan Colin Derdeyn Biyue Dai Harold Adams Enrique Leira Neurology Neurosurgery and RadiologyUniversity of Iowa Hospitals and ClinicsIowa CityIowaUSA Neurology University of Iowa Hospitals and ClinicsIowa CityIowaUSA Neurology and Neurosurgery University of Iowa Hospitals and ClinicsIowa CityIowaUSA Neurosurgery University of Iowa Hospitals and ClinicsIowa CityIowaUSA Radiology University of Iowa Hospitals and ClinicsIowa CityIowaUSA Biostatistics and Public Health University of Iowa Hospitals and ClinicsIowa CityIowaUSA

background While diffuse atherosclerotic disease affecting the posterior circulation has been described extensively,the prevalence,natural history and angiographic characteristics of isolated symptomatic basilar artery stenosis(ISBAS)remain *** We reviewed our prospective institutional database to identify patients with≥50% symptomatic basilar artery(BA)stenosis without significant atherosclerotic burden in the vertebral or posterior cerebral *** mechanism,collateral circulation,and degree and length of stenosis were *** primary outcome was time from index event to new transient ischaemic attack(TIA),acute ischaemic stroke(AIS)or *** outcome variables included modified Rankin Scale(mRS)score on discharge and last *** Of 6369 patients with AIS/TIA,91(1.43%)had ***-three(80.2%)patients presented with AIS and 18(19.8%)with ***-nine(31.9%)were women and the median age was 66.8±13.6 *** mean follow-up time was 2.7 *** most common stroke mechanism was artery-to artery thromboembolism(45.2%),followed by perforator occlusion(28.7%)and flow-dependent/hypoperfusion(15.1%).The percentage of stenosis was lower in patients who had favourable outcome compared with those with mRS 3-6 on discharge(78.3±14.3 vs 86.9±14.5,p=0.007).Kaplan-Meier curves showed higher recurrence/death rates in patients with≥80% stenosis,mid-basilar location and poor collateral *** 13% of patients with ISBAS presented with complete BA *** ISBAS is an uncommon(1.43%)cause of TIA and *** in their 60s are mostly affected,and artery-to artery embolism is the most common stroke ***-basilar location,≥80% stenosis and poor collateral circulation are important factors associated with worse prognosis.

关键词： stenosis basilar artery

Mixed-conducting ceramic–carbonate membranes exhibiting high CO2/O2 permeation flux and stability at high temperatures

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Journal of Advanced Ceramics 2020年第1期9卷 94-106页

作者： R.ortega-LUGO J.A.FABIAN-ANGUIANO O.OVALLE-ENCINIA C.GOMEZ-YANEZ B.H.ZEIFERT J.ORTIZ-LANDEROS Instituto Politécnico Nacional Escuela Superior de Ingeniería Química e Industrias ExtractivasDepartamento de Ingeniería en Metalurgia y MaterialesUPALM-ZacatencoMexico City 07738Mexico Chemical Engineering School for Engineering of Matter Transport and EnergyArizona State UniversityTempeAZ 85287-6106USA

This investigation demonstrates the feasibility to fabricate high quality ceramic–carbonate membranes based on mixed-conducting ***,it is reported the simultaneous CO2/O2 permeation and stability properties of membranes constituted by a combination of ceramic and carbonate phases,wherein the microstructure of the ceramic part is composed,in turn,of a mixture of fluorite and perovskite *** ceramics showed ionic and electronic conduction,and at the operation temperature,the carbonate phase of the membranes is in liquid state,which allows the transport of CO32-and O2–species via different *** fabricate the membranes,the ceramic powders were uniaxially pressed in a disk ***,an incipient sintering treatment was carried out in such a way that a highly porous ceramic was ***,the piece is densified by the infiltration of molten *** of the membranes was accomplished by SEM,XRD,and gas permeation techniques among *** and chemical stability under an atmosphere rich in CO2 was ***2/O2 permeation and long-term stability measurements were conducted between 850 and 940℃.The best permeation–separation performance of membranes of about 1 mm thickness,showed a maximum permeance flux of about 4.46×10^–7 mol·m^–2·s^–1·Pa^–1 for CO2 and 2.18×10^–7 mol·m^–2·s^–1·Pa^–1 for O2 at 940℃.Membranes exhibited separation factor values of 150–991 and 49–511 for CO2/N2 and O2/N2 respectively in the studied temperature *** long-term stability test showed certain microstructural changes in the membranes,no significant detriment on the permeation properties was observed along 100 h of continuous operation.

关键词： CO2 separation O2 separation ceramic–carbonate membrane selectivity

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E-DNA scaffold sensors and the reagentless, single- step, measurement of HIV-diagnostic antibodies in human serum

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Microsystems & Nanoengineering 2020年第1期6卷 1141-1148页

作者： Claudio Parolo Ava S.Greenwood Nathan E.Ogden Di Kang Chase Hawes Gabriel ortega Netzahualcoyotl Arroyo-Curras Kevin W.Plaxco Department of Chemistry and Biochemistry University of CaliforniaSanta BarbaraSanta BarbaraCAUSA Department of Materials University of CaliforniaSanta BarbaraSanta BarbaraCAUSA Department of Pharmacology and molecular Sciences Johns Hopkins School of MedicineBaltimoreMD 21205USA Interdepartmental Program in Biomolecular Science and Engineering University of CaliforniaSanta BarbaraSanta BarbaraCA 93106USA

The multiplexed,point-of-care measurement of specific antibodies could improve the speed with which diseases are diagnosed and their treatment *** this end,we are developing E-DNA scaffold sensors,which consist of a rigid,nucleic acid“scaffold”attached on one end to an electrode and presenting both a redox reporter and an epitope on the *** the absence of antibody,the reporter efficiently transfers electrons when interrogated ***-induced steric hindrance limits movement,reducing electron transfer in a manner that is both easily measured and quantitatively related to target *** we have used monoclonal antibodies to explore the analytical performance of E-DNA sensors,showing that they support the rapid,single-step,quantitative detection of multiple antibodies in small volume ***,in contrast,we employ authentic human samples to better explore the platform’s clinical ***,we developed E-DNA sensors targeting three HIV-specific antibodies and then compared the analytical and clinical performance of these against those of gold standard serological *** so we find that,although the multistep amplification of an ELISA leads to a lower detection limits,the clinical sensitivity of ELISAs,E-DNA sensors and lateral-flow dipsticks are indistinguishable across our test *** thus appears that,by merging the quantitation and multiplexing of ELISAs with the convenience and speed of dipsticks,E-DNA scaffold sensors could significantly improve on current serological practice.

关键词： antibodies attached initiated

International NeuroAIDS: prospects of HIV-1 associated neurological com-plications

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Cell Research 2005年第Z1期15卷 962-969页

作者： J Roberto TRUJILLO Gilberto JARAMILLO-RANGEL Marta ortega-MARTINEZ Augusto C PENALVA de OLIVEIRA Jose E VIDAL Joseph BRYANT Robert C GALLO Institute of Human Virology University of Maryland Biotechnology Institute 725 W Lombard Street Baltimore MD 21201 USA Institute of Infectious Diseases Emilio Ribas Sao Paulo 01246 Brazil Clinical Research Unit in Human Retrovirology University of CampinasSao Paulo 01246 Brazil. Institute of Infectious Diseases Emilio Ribas Sao Paulo 01246 Brazil

Neurological complications associated with HIV-1/AIDS are being recognized with a high frequency that parallels the increased number of AIDS cases. The early infiltration by HIV-1 into the nervous system can cause primary and/or secondary neurological complications. The most common neurocognitive disorder is AIDS Dementia Complex (ADC). In developing countries of Asia the three most opportunistic infections are tuberculosis (TB), cryptococcosis, and Pneumocystis carinii pneumonia. Therefore, it is expected that secondary neurological complications due to TB and cryptococcosis will be the most common cause of morbility and mortality in HIV-1/AIDS cases in China. Research of NeuroAIDS in China is necessary to understand the impact and the biology of HIV-1 in the nervous system. Future studies would include, the molecular epidemiology and the description of opportunistic infections associated to HIV-1; the neuropathological description of primary and secondary HIV-1 complications in different groups; the HIV-1 neurot- ropism and immune response studies for China’s unique HIV-1 strains and recombinant forms derived from the nervous system, including experimental models such as the use of transgenic rats; and the study of potential resistant virus, primarily when the anti-retroviral therapy (ART) has not full access in the brain.

关键词： NeuroAIDS HIV-1 neurotropism AIDS dementia complex.

Potential Applications of Milk Fractions and Valorization of Dairy By-Products: A Review of the State-of-the-Art Available Data, Outlining the Innovation Potential from a Bigger Data Standpoint

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Journal of Biomaterials and Nanobiotechnology 2015年第3期6卷 176-203页

作者： Serge Rebouillat Salvadora ortega-Requena Currently with DuPont Int. Op. European Headquarter Geneva Switzerland Chemical Engineering Department University of Murcia Murcia Spain

The unique composition of milk makes this basic foodstuff into an exceptional raw material for the production of new ingredients with desired properties and diverse applications in the food industry. The fractionation of milk is the key in the development of those ingredients and products;hence continuous research and development on this field, especially various levels of fractionation and separation by filtration, have been carried out. This review focuses on the production of milk fractions as well as their particular properties, applications and processes that increase their exploitation. Whey proteins and caseins from the protein fraction are excellent emulsifiers and protein supplements. Besides, they can be chemically or enzymatically modified to obtain bioactive peptides with numerous functional and nutritional properties. In this context, valorization techniques of cheese-whey proteins, by-product of dairy industry that constitutes both economic and environmental problems, are being developed. Phospholipids from the milk fat fraction are powerful emulsifiers and also have exclusive nutraceutical properties. In addition, enzyme modification of milk phospholipids makes it possible to tailor emulsifiers with particular properties. However, several aspects remain to be overcome;those refer to a deeper understanding of the healthy, functional and nutritional properties of these new ingredients that might be barriers for its use and acceptability. Additionally, in this review, alternative applications of milk constituents in the non-food area such as in the manufacture of plastic materials and textile fibers are also introduced. The unmet needs, the cross-fertilization in between various protein domains,the carbon footprint requirements, the environmental necessities, the health and wellness new demand, etc., are dominant factors in the search for innovation approaches;these factors are also outlining the further innovation potential deriving from those “apparent

关键词： Milk Product Milk Fractionation Casein Phospholipid Whey Protein Non-Food Application Valorization Enzyme modification Bioactive Peptides Bigger Data Innovation: Closed Open Collaborative Disruptive Inclusive Nested

Coping with drought?Effects of extended drought conditions on soil invertebrate prey and diet selection by a fossorial amphisbaenian reptile

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Current Zoology 2023年第4期69卷 367-376页

作者： José Martín Jesús ortega Roberto García-Roa Gonzalo Rodríguez-Ruiz Ana Pérez-Cembranos Valentín Pérez-Mellado Departamento de Ecología Evolutiva Museo Nacional de Ciencias NaturalesCSICMadridSpain Institute of Evolutionary Biology CSIC-Universitat Pompeu FabraBarcelonaSpain Ethology Lab Cavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of ValenciaValenciaSpain Departamento de Biología Animal Universidad de SalamancaSalamancaSpain

Arid climates are characterized by a summer drought period to which animals seem ***,in some years,the drought can extend for unusually longer *** the effects of these current extreme weather events on biodiversity can help to understand the effects of climate change,as models predict an increase in drought ***,we examined the effects of“unusual”extended drought on soil invertebrate prey availability and on diet composition(based on fecal contents)and diet selection of a fossorial amphisbaenian,the checkerboard worm lizard Trogonophis *** data show interannual variations in summer drought *** abundance and diversity of soil invertebrates in spring were high,and similar to those found in a“normal”early autumn,after some rain had ended with the summer *** contrast,in years with“unusual”extended drought,abundance,and diversity of soil invertebrates in early autumn were very ***,there were seasonal changes in amphisbaenians’diet;in autumn with drought,prey diversity,and niche breadth decreased with respect to spring and autumns after some rain had *** did not eat prey at random in any season,but made some changes in prey selection that may result from drought-related restrictions in prey ***,in spite that amphisbaenians showed some feeding flexibility,their body condition was lower in autumn than in spring,and much lower in autumn with *** extended drought became the norm in the future,amphisbaenians might suffer important negative effects for their health state.

关键词： amphisbaenians drought feeding ecology soil invertebrates Trogonophis wiegmanni weather conditions

New Results on Interconnection and Damping Assignment Passivity-Based Control

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New Results on Interconnection and Damping Assignment Passiv...

Cell cycle reactivation in mature neurons: a link with brain plasticity, neuronal injury and neurodegenerative diseases?

第二十二届中国控制会议

作者： Romeo ortega Laboratoire des Signaux et Systémes Supelec91192Gif-sur-YvetteFrance

＜正＞Interconnection and Damping Assignment Passivity-based Control is a technique which achieves stabilization of nonlinear systems assigning a desired （port-controlled Hamiltonian） structure to the closed-loop. Since the introduction of this controller design methodology four years ago many theoretical extensions and practical applications have been reported in the literature. The theoretical developments include some useful variations and shortcuts that may be introduced when the technique is applied to particular classes of systems and the incorporation of additional features to handle control scenarios other than just stabilization. The purposes of this paper are to collect and present in a unified way some of the new theoretical results and to discuss the current research and future directions.

关键词： Passivity nonlinear systems stabilization passivity-based control Hamiltonian systems.

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Neuroscience Bulletin 2011年第3期27卷 185-196页

作者： Karina Hernández-ortega Ricardo Quiroz-Baez Clorinda Arias 墨西哥国立大学生物医学研究所基因组医学与环境毒理学研究室墨西哥国立卫生研究院老年医学研究所

Although the cell cycle machinery is essentially linked to cellular proliferation, recent findings suggest that neuronal cell death is frequently concurrent with the aberrant expression of cell cycle proteins in post-mitotic neurons. The present work reviews the evidence of cell cycle reentry and expression of cell cycle-associated proteins as a complex response of neurons to insults in the adult brain but also as a mechanism underlying brain plasticity. The basic aspects of cell cycle mechanisms, as well as the evidence showing cell cycle protein expression in the injured brain, are reviewed. The discussion includes recent experimental work attempting to establish a correlation between altered brain plasticity and neuronal death, and an analysis of recent evidence on how neural cell cycle dysregulation is related to neurodegenerative diseases especially the Alzheimer＇s disease. Understanding the mechanisms that control reexpression of proteins required for cell cycle progression which is involved in brain remodeling, may shed new light into the mechanisms involved in neuronal demise under diverse pathological circumstances. This would provide valuable clues about the possible therapeu tic targets, leading to potential treatment of presently challenging neurodegenerative diseases.

关键词： Alzheimer's disease cell cycle neurodegeneration brain plasticity

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