30 results on '"Fernández LJ"'
Search Results
2. Cystic adventitial disease of the popliteal artery: Two case reports and a review of the literature.
- Author
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Del Canto Peruyera, P, Vázquez, MJ Vallina-Victorero, Velasco, M Botas, Álvarez, P Calvín, Salgado, A Álvarez, Álvarez, J Cerviño, and Fernández, LJ Álvarez
- Abstract
Two cases of cystic adventitial disease treated at our institution over the last year are presented. They were middle-aged and apparently healthy patients, and the symptoms begin with a sudden onset of unilateral claudication. After performing a magnetic resonance angiography, a cystic formation attached to the adventitia of the popliteal artery was identified. Both patients were treated in the same manner, with resection of the affected arterial segment and vein bypass interposition. Both remain asymptomatic after one year of follow-up in one case and six months in the other. Cystic adventitial disease is a rare entity, which presents in patients without cardiovascular risk factors, so sometimes it takes long to reach a definitive diagnosis. Concerning the different treatment options, cyst excision together with the affected arterial segment seems to offer better mid- and long-term results when compared with other treatment options such as cyst aspiration or endovascular techniques, although there are no multicenter trials evidencing the superiority of one against the others. [ABSTRACT FROM PUBLISHER]
- Published
- 2015
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3. Recirculating packed-bed biofilm photobioreactor combined with membrane ultrafiltration as advanced wastewater treatment.
- Author
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Díaz O, González E, Vera L, Fernández LJ, Díaz-Marrero AR, and Fernández JJ
- Subjects
- Photobioreactors microbiology, Wastewater, Ultrafiltration, Nitrification, Biofilms, Biomass, Nitrogen, Bioreactors, Denitrification, Water Purification, Microalgae
- Abstract
Packed-bed biofilm photobioreactor combined with ultrafiltration membrane was investigated for intensifying the process for secondary wastewater effluent treatment. Cylindrical glass carriers were used as supporting material for the microalgal-bacterial biofilm, which developed from indigenous microbial consortium. Glass carriers allowed adequate growth of the biofilm with limited suspended biomass. Stable operation was achieved after a start-up period of 1000 h, where supernatant biopolymer clusters were minimized and complete nitrification was observed. After that time, biomass productivity was 54 ± 18 mg·L
-1 ·day-1 . Green microalgae Tetradesmus obliquus and several strains of heterotrophic nitrification-aerobic denitrification bacteria and fungi were identified. Combined process exhibited COD, nitrogen and phosphorus removal rates of 56 ± 5%, 12 ± 2% and 20 ± 6%, respectively. Membrane fouling was mainly caused by biofilm formation, which was not effectively mitigated by air-scouring aided backwashing., (© 2023. The Author(s).)- Published
- 2023
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4. Force spectroscopy-based simultaneous topographical and mechanical characterization to study polymer-to-polymer interactions in coated alginate microspheres.
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Virumbrales-Muñoz M, Santos-Vizcaino E, Paz L, Gallardo-Moreno AM, Orive G, Hernandez RM, Doblaré M, Gonzalez-Martin ML, Fernández LJ, Pedraz JL, and Ochoa I
- Abstract
Cell-laden hydrogel microspheres have shown encouraging outcomes in the fields of drug delivery, tissue engineering or regenerative medicine. Beyond the classical single coating with polycations, many other different coating designs have been reported with the aim of improving mechanical properties and in vivo performance of the microspheres. Among the most common strategies are the inclusion of additional polycation coatings and the covalent bonding of the semi-permeable membranes with biocompatible crosslinkers such as genipin. However, it remains challenging to characterize the effects of the interactions between the polycations and the hydrogel microspheres over time in vitro. Here we use a force spectroscopy-based simultaneous topographical and mechanical characterization to study polymer-to-polymer interactions in alginate microspheres with different coating designs, maintaining the hydrogels in liquid. In addition to classical topography parameters, we explored, for the first time, the evolution of peak/valley features along the z axis via thresholding analysis and the cross-correlation between topography and stiffness profiles with resolution down to tens of nanometers. Thus, we demonstrated the importance of genipin crosslinking to avoid membrane detachment in alginate microspheres with double polycation coatings. Overall, this methodology could improve hydrogel design rationale and expedite in vitro characterization, therefore facilitating clinical translation of hydrogel-based technologies.
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- 2019
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5. Modulation of Antioxidant Potential with Coenzyme Q10 Suppressed Invasion of Temozolomide-Resistant Rat Glioma In Vitro and In Vivo .
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Burić SS, Podolski-Renić A, Dinić J, Stanković T, Jovanović M, Hadžić S, Ayuso JM, Virumbrales-Muñoz M, Fernández LJ, Ochoa I, Pérez-García VM, and Pešić M
- Subjects
- Animals, Brain Neoplasms pathology, Drug Resistance, Neoplasm, Glioblastoma pathology, Humans, Male, Mice, Rats, Wistar, Temozolomide pharmacology, Ubiquinone pharmacology, Ubiquinone therapeutic use, Antioxidants therapeutic use, Brain Neoplasms drug therapy, Glioblastoma drug therapy, Temozolomide therapeutic use, Ubiquinone analogs & derivatives
- Abstract
The main reasons for the inefficiency of standard glioblastoma (GBM) therapy are the occurrence of chemoresistance and the invasion of GBM cells into surrounding brain tissues. New therapeutic approaches obstructing these processes may provide substantial survival improvements. The purpose of this study was to assess the potential of lipophilic antioxidant coenzyme Q10 (CoQ10) as a scavenger of reactive oxygen species (ROS) to increase sensitivity to temozolomide (TMZ) and suppress glioma cell invasion. To that end, we used a previously established TMZ-resistant RC6 rat glioma cell line, characterized by increased production of ROS, altered antioxidative capacity, and high invasion potential. CoQ10 in combination with TMZ exerted a synergistic antiproliferative effect. These results were confirmed in a 3D model of microfluidic devices showing that the CoQ10 and TMZ combination is more cytotoxic to RC6 cells than TMZ monotherapy. In addition, cotreatment with TMZ increased expression of mitochondrial antioxidant enzymes in RC6 cells. The anti-invasive potential of the combined treatment was shown by gelatin degradation, Matrigel invasion, and 3D spheroid invasion assays as well as in animal models. Inhibition of MMP9 gene expression as well as decreased N-cadherin and vimentin protein expression implied that CoQ10 can suppress invasiveness and the epithelial to mesenchymal transition in RC6 cells. Therefore, our data provide evidences in favor of CoQ10 supplementation to standard GBM treatment due to its potential to inhibit GBM invasion through modulation of the antioxidant capacity.
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- 2019
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6. A Label Free Disposable Device for Rapid Isolation of Rare Tumor Cells from Blood by Ultrasounds.
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González I, Earl J, Fernández LJ, Sainz B, Pinto A, Monge R, Alcalá S, Castillejo A, Soto JL, and Carrato A
- Abstract
The use of blood samples as liquid biopsy is a label-free method for cancer diagnosis that offers benefits over traditional invasive biopsy techniques. Cell sorting by acoustic waves offers a means to separate rare cells from blood samples based on their physical properties in a label-free, contactless and biocompatible manner. Herein, we describe a flow-through separation approach that provides an efficient separation of tumor cells (TCs) from white blood cells (WBCs) in a microfluidic device, "THINUS-Chip" (Thin-Ultrasonic-Separator-Chip), actuated by ultrasounds. We introduce for the first time the concept of plate acoustic waves (PAW) applied to acoustophoresis as a new strategy. It lies in the geometrical chip design: different to other microseparators based on either bulk acoustic waves (BAW) or surface waves (SAW, SSAW and tSAW), it allows the use of polymeric materials without restrictions in the frequency of work. We demonstrate its ability to perform high-throughput isolation of TCs from WBCs, allowing a recovery rate of 84% ± 8% of TCs with a purity higher than 80% and combined viability of 85% at a flow rate of 80 μL/min (4.8 mL/h). The THINUS-Chip performs cell fractionation with low-cost manufacturing processes, opening the door to possible easy printing fabrication., Competing Interests: The authors have no conflicts of interest.
- Published
- 2018
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7. Glioblastoma on a microfluidic chip: Generating pseudopalisades and enhancing aggressiveness through blood vessel obstruction events.
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Ayuso JM, Monge R, Martínez-González A, Virumbrales-Muñoz M, Llamazares GA, Berganzo J, Hernández-Laín A, Santolaria J, Doblaré M, Hubert C, Rich JN, Sánchez-Gómez P, Pérez-García VM, Ochoa I, and Fernández LJ
- Subjects
- Cell Hypoxia, Cell Line, Tumor, Humans, Microfluidics, Models, Neurological, Brain Neoplasms blood supply, Brain Neoplasms physiopathology, Glioblastoma blood supply, Glioblastoma physiopathology, Lab-On-A-Chip Devices, Microfluidic Analytical Techniques instrumentation, Microfluidic Analytical Techniques methods
- Abstract
Background: Glioblastoma (GBM) is one of the most lethal tumor types. Hypercellular regions, named pseudopalisades, are characteristic in these tumors and have been hypothesized to be waves of migrating glioblastoma cells. These "waves" of cells are thought to be induced by oxygen and nutrient depletion caused by tumor-induced blood vessel occlusion. Although the universal presence of these structures in GBM tumors suggests that they may play an instrumental role in GBM's spread and invasion, the recreation of these structures in vitro has remained challenging., Methods: Here we present a new microfluidic model of GBM that mimics the dynamics of pseudopalisade formation. To do this, we embedded U-251 MG cells within a collagen hydrogel in a custom-designed microfluidic device. By controlling the medium flow through lateral microchannels, we can mimic and control blood-vessel obstruction events associated with this disease., Results: Through the use of this new system, we show that nutrient and oxygen starvation triggers a strong migratory process leading to pseudopalisade generation in vitro. These results validate the hypothesis of pseudopalisade formation and show an excellent agreement with a systems-biology model based on a hypoxia-driven phenomenon., Conclusions: This paper shows the potential of microfluidic devices as advanced artificial systems capable of modeling in vivo nutrient and oxygen gradients during tumor evolution., (© The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com)
- Published
- 2017
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8. High-order TRAIL oligomer formation in TRAIL-coated lipid nanoparticles enhances DR5 cross-linking and increases antitumour effect against colon cancer.
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De Miguel D, Gallego-Lleyda A, Ayuso JM, Pejenaute-Ochoa D, Jarauta V, Marzo I, Fernández LJ, Ochoa I, Conde B, Anel A, and Martinez-Lostao L
- Subjects
- Animals, Antineoplastic Agents chemistry, Caco-2 Cells, Cell Survival drug effects, Colonic Neoplasms genetics, Colonic Neoplasms metabolism, Colonic Neoplasms pathology, Cross-Linking Reagents chemistry, Dose-Response Relationship, Drug, Drug Compounding, Drug Resistance, Neoplasm, HCT116 Cells, HT29 Cells, Humans, Inhibitory Concentration 50, Male, Mice, Nude, Protein Conformation, Receptors, TNF-Related Apoptosis-Inducing Ligand metabolism, Signal Transduction drug effects, TNF-Related Apoptosis-Inducing Ligand chemistry, Time Factors, Tumor Burden drug effects, Xenograft Model Antitumor Assays, bcl-2-Associated X Protein genetics, bcl-2-Associated X Protein metabolism, Antineoplastic Agents administration & dosage, Apoptosis drug effects, Colonic Neoplasms drug therapy, Cross-Linking Reagents administration & dosage, Drug Carriers, Lipids chemistry, Nanoparticles, Receptors, TNF-Related Apoptosis-Inducing Ligand agonists, TNF-Related Apoptosis-Inducing Ligand administration & dosage
- Abstract
During the last years, a great effort has been invested into developing new TRAIL formulations with increased bioactivity, trying to overcome the resistance to conventional soluble TRAIL (sTRAIL) exhibited by many primary tumours. In our group, we have generated artificial lipid nanoparticles decorated with sTRAIL (LUV-TRAIL), emulating the physiological TRAIL-containing exosomes by which T-cells release TRAIL upon activation. We already demonstrated that LUV-TRAIL has greater cytotoxicity against both chemoresistant haematologic tumour cells and epithelial carcinoma cells compared to a form of sTRAIL similar to that used in clinical trials. In this study we have tested LUV-TRAIL in several human colon cancer cell lines with different sensitivity to sTRAIL. LUV-TRAIL significantly improved sTRAIL cytotoxicity in all colon cancer cell lines tested. Trying to ascertain the molecular mechanism by which LUV-TRAIL exhibited improved cytotoxicity, we demonstrated that TRAIL-coated lipid nanoparticles were able to activate DR5 more efficiently than sTRAIL, and this relied on LUV-TRAIL ability to promote DR5 clustering on the cell surface. Moreover, we show that TRAIL molecules are arranged in higher order oligomers only in LUV-TRAIL, which may explain their enhanced DR5 clustering ability. Finally, LUV-TRAIL showed significantly better antitumour activity than sTRAIL in an in vivo model using HCT-116 xenograft tumours in nude mice, validating its potential clinical application., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2016
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9. Prevention of Bone Loss in a Model of Postmenopausal Osteoporosis through Adrenomedullin Inhibition.
- Author
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Martínez-Herrero S, Larrayoz IM, Ochoa-Callejero L, Fernández LJ, Allueva A, Ochoa I, and Martínez A
- Abstract
Despite recent advances in the understanding and treatment options for osteoporosis, this condition remains a serious public health issue. Adrenomedullin (AM) is a regulatory peptide with reported activity on bone remodeling. To better understand this relationship we built an inducible knockout for AM. An outstanding feature of knockout mice is their heavier weight due, in part, to the presence of denser bones. The femur of knockout animals was denser, had more trabeculae, and a thicker growth plate than wild type littermates. The endocrine influence of AM on bone seems to be elicited through an indirect mechanism involving, at least, the regulation of insulin, glucose, ghrelin, and calcitonin gene-related peptide (CGRP). To confirm the data we performed a pharmacological approach using the AM inhibitor 16311 in a mouse model of osteoporosis. Ovariectomized females showed significant bone mass loss, whereas ovariectomized females treated with 16311 had similar bone density to sham operated females. In conclusion, we propose the use of AM inhibitors for the treatment of osteoporosis and other conditions leading to the loss of bone mass.
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- 2016
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10. Resistance to DNA Damaging Agents Produced Invasive Phenotype of Rat Glioma Cells-Characterization of a New in Vivo Model.
- Author
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Stojković S, Podolski-Renić A, Dinić J, Pavković Ž, Ayuso JM, Fernández LJ, Ochoa I, Pérez-García VM, Pešić V, and Pešić M
- Subjects
- Animals, Behavior, Animal drug effects, Brain Neoplasms drug therapy, Cell Movement drug effects, Cell Proliferation drug effects, Disease Models, Animal, Glioma drug therapy, Humans, Motor Activity drug effects, Neoplasm Invasiveness, Rats, Antineoplastic Agents, Alkylating pharmacology, Brain Neoplasms genetics, Brain Neoplasms pathology, DNA Damage drug effects, Drug Resistance, Neoplasm, Glioma genetics, Glioma pathology
- Abstract
Chemoresistance and invasion properties are severe limitations to efficient glioma therapy. Therefore, development of glioma in vivo models that more accurately resemble the situation observed in patients emerges. Previously, we established RC6 rat glioma cell line resistant to DNA damaging agents including antiglioma approved therapies such as 3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and temozolomide (TMZ). Herein, we evaluated the invasiveness of RC6 cells in vitro and in a new orthotopic animal model. For comparison, we used C6 cells from which RC6 cells originated. Differences in cell growth properties were assessed by real-time cell analyzer. Cells' invasive potential in vitro was studied in fluorescently labeled gelatin and by formation of multicellular spheroids in hydrogel. For animal studies, fluorescently labeled cells were inoculated into adult male Wistar rat brains. Consecutive coronal and sagittal brain sections were analyzed 10 and 25 days post-inoculation, while rats' behavior was recorded during three days in the open field test starting from 25th day post-inoculation. We demonstrated that development of chemoresistance induced invasive phenotype of RC6 cells with significant behavioral impediments implying usefulness of orthotopic RC6 glioma allograft in preclinical studies for the examination of new approaches to counteract both chemoresistance and invasion of glioma cells.
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- 2016
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11. TRAIL-coated lipid-nanoparticles overcome resistance to soluble recombinant TRAIL in non-small cell lung cancer cells.
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De Miguel D, Gallego-Lleyda A, Ayuso JM, Erviti-Ardanaz S, Pazo-Cid R, del Agua C, Fernández LJ, Ochoa I, Anel A, and Martinez-Lostao L
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- Antineoplastic Agents chemistry, Carcinoma, Non-Small-Cell Lung drug therapy, Caspase 3 metabolism, Caspase 8 metabolism, Cell Line, Tumor, Cell Survival drug effects, Gene Expression Regulation, Neoplastic, Humans, Liposomes, Lung Neoplasms drug therapy, Recombinant Proteins chemistry, Recombinant Proteins pharmacology, TNF-Related Apoptosis-Inducing Ligand chemistry, Antineoplastic Agents pharmacology, Carcinoma, Non-Small-Cell Lung metabolism, Lung Neoplasms metabolism, Nanoparticles chemistry, TNF-Related Apoptosis-Inducing Ligand pharmacology
- Abstract
Purpose: Non-small cell lung cancer (NSCLC) is one the types of cancer with higher prevalence and mortality. Apo2-Ligand/TRAIL is a TNF family member able to induce apoptosis in tumor cells but not in normal cells. It has been tested in clinical trials against different types of human cancer including NSCLC. However, results of clinical trials have shown a limited efficacy of TRAIL-based therapies. Recently we have demonstrated that artificial lipid nanoparticles coated with bioactive Apo2L/TRAIL (LUV-TRAIL) greatly improved TRAIL cytotoxic ability being capable of killing chemoresistant hematological cancer cells. In the present work we have extended the study to NSCLC., Methods/patients: LUV-TRAIL-induced cytotoxicity was assessed on different NSCLC cell lines with different sensitivity to soluble TRAIL and on primary human tumor cells from three patients suffering from NSCLC cancer. We also tested LUV-TRAIL-cytotoxic ability in combination with several anti-tumor agents., Results: LUV-TRAIL exhibited a greater cytotoxic effect compared to soluble TRAIL both in A549 cells and primary human NSCLC cells. LUV-TRAIL-induced cell death was dependent on caspase-8 and caspase-3 activation. Moreover, combination of LUV-TRAIL with other anti-tumor agents such as flavopiridol, and SNS-032 clearly enhanced LUV-TRAIL-induced cytotoxicity against NSCLC cancer cells., Conclusion: The novel formulation of TRAIL based on displaying it on the surface of lipid nanoparticles greatly increases its anti-tumor activity and has clinical potential in cancer treatment.
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- 2016
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12. Improved Anti-Tumor Activity of Novel Highly Bioactive Liposome-Bound TRAIL in Breast Cancer Cells.
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De Miguel D, Gallego-Lleyda A, Ayuso JM, Pawlak A, Conde B, Ochoa I, Fernández LJ, Anel A, and Martinez-Lostao L
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- Animals, Breast Neoplasms drug therapy, Cell Line, Tumor, Cell Survival drug effects, Cell Survival physiology, Drug Compounding, Female, Humans, Liposomes, Mice, Mice, Nude, Xenograft Model Antitumor Assays methods, Antineoplastic Agents administration & dosage, Antineoplastic Agents metabolism, Breast Neoplasms metabolism, TNF-Related Apoptosis-Inducing Ligand administration & dosage, TNF-Related Apoptosis-Inducing Ligand metabolism
- Abstract
Background: Apo2-ligand/TRAIL, a member of the TNF cytokine superfamily capable of inducing apoptosis on tumor cells while sparing normal cells, is a promising anti-tumor agent. However, about 50% of human cancer are TRAIL resistant. Consequently, future TRAIL-based therapies will require the use of novel highly bioactive forms of TRAIL and/or the addition of sensitizing agents to TRAIL-induced apoptosis. Recently, we demonstrated that artificial lipid nanoparticles coated with bioactive TRAIL (LUV-TRAIL) greatly improved TRAIL activity and were able to induce apoptosis in chemoresistant hematological tumor cells., Objective: In this study, we have tested LUV-TRAIL-pro-apoptotic potential in human breast cancer., Method: Comparative analysis of cytotoxicity induced by sTRAIL and LUV-TRAIL was performed using several human breast tumor cell lines with different sensitivity to TRAIL. In vivo anti-tumor activity of LUV-TRAIL was also studied using a xeno-graft tumor model., Results: LUV-TRAIL improved not only sTRAIL in vitro cytotoxicity in all breast tumor cell lines tested but also showed more anti-tumor activity than sTRAIL in an in vivo xeno-graft tumor model. On the other hand, the concomitant treatment of LUV-TRAIL with the sensitizing agent flavopiridol (FVP) induced a higher level of cell death in TRAIL-resistant cell lines. TRAIL-sensitization induced by FVP was mediated by DR5 up-regulation, and interestingly TRAIL-apoptotic signaling was completely shifted towards DR5 upon FVP treatment. LUV-TRAIL could especially take advantage of this DR5 up-regulation, while sTRAIL was not able., Conclusion: To date, no special attention had been paid to this aspect of FVP-induced TRAIL-sensitization, may be because sTRAIL used were not able to take advantage of this DR5 up-regulation. Hence, LUV-TRAIL could be a better choice than sTRAIL to be used in combination with anti-tumor drugs inducing DR5 over-expression, since LUV-TRAIL is especially effective activating this death-receptor.
- Published
- 2016
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13. Hypoxia in Gliomas: Opening Therapeutical Opportunities Using a Mathematical-Based Approach.
- Author
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Martı Nez-González A, Calvo GF, Ayuso JM, Ochoa I, Fernández LJ, and Pérez-García VM
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- Astrocytes drug effects, Astrocytes pathology, Brain Neoplasms blood supply, Brain Neoplasms complications, Brain Neoplasms metabolism, Cell Count, Cell Movement drug effects, Cell Transformation, Neoplastic drug effects, Glioma blood supply, Glioma complications, Glioma metabolism, Humans, Lab-On-A-Chip Devices, Neoplasm Grading, Neoplasm Invasiveness, Oligodendroglia drug effects, Oligodendroglia pathology, Thromboembolism complications, Thromboembolism pathology, Tumor Microenvironment drug effects, Venous Thrombosis complications, Venous Thrombosis pathology, Brain Neoplasms drug therapy, Fibrinolytic Agents therapeutic use, Glioma drug therapy, Models, Statistical, Thromboembolism prevention & control, Tumor Hypoxia, Venous Thrombosis prevention & control
- Abstract
This chapter explores the use of mathematical models as promising and powerful tools to understand the complexity of tumors and their, frequently, hypoxic environment. We focus on gliomas, which are primary brain tumors derived from glial cells, mainly astrocytes and/or oligodendrocytes. A variety of mathematical models, based on ordinary and/or partial differential equations, have been developed both at the micro and macroscopic levels. The aim here is to describe in a quantitative way key physiopathological mechanisms relevant in these types of malignancies and to suggest optimal therapeutical strategies. More specifically, we consider novel therapies targeting thromboembolic phenomena to decrease cell invasion in high grade glioma or to delay the malignant transformation in low grade gliomas. This study has been the basis of a multidisciplinary collaboration involving, among others, neuro-oncologists, radiation oncologists, pathologists, cancer biologists, surgeons and mathematicians.
- Published
- 2016
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14. Images in vascular medicine. Endovascular treatment of a giant splenic aneurysm.
- Author
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Suárez González LÁ, Botas Velasco M, Del Canto Peruyera P, Cerviño Álvarez J, and Álvarez Fernández LJ
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- Aged, 80 and over, Aneurysm diagnostic imaging, Female, Humans, Tomography, X-Ray Computed, Treatment Outcome, Aneurysm therapy, Endovascular Procedures instrumentation, Splenic Artery diagnostic imaging
- Published
- 2015
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15. Study of the Chemotactic Response of Multicellular Spheroids in a Microfluidic Device.
- Author
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Ayuso JM, Basheer HA, Monge R, Sánchez-Álvarez P, Doblaré M, Shnyder SD, Vinader V, Afarinkia K, Fernández LJ, and Ochoa I
- Subjects
- Animals, Carcinoma, Squamous Cell metabolism, Carcinoma, Squamous Cell pathology, Cattle, Cell Line, Tumor, Cell Movement physiology, Humans, Lab-On-A-Chip Devices, Mouth Neoplasms metabolism, Mouth Neoplasms pathology, Serum metabolism, Spheroids, Cellular metabolism, Cell Culture Techniques instrumentation, Cell Culture Techniques methods, Chemotactic Factors metabolism, Chemotaxis physiology, Microfluidic Analytical Techniques instrumentation, Microfluidic Analytical Techniques methods, Spheroids, Cellular physiology
- Abstract
We report the first application of a microfluidic device to observe chemotactic migration in multicellular spheroids. A microfluidic device was designed comprising a central microchamber and two lateral channels through which reagents can be introduced. Multicellular spheroids were embedded in collagen and introduced to the microchamber. A gradient of fetal bovine serum (FBS) was established across the central chamber by addition of growth media containing serum into one of the lateral channels. We observe that spheroids of oral squamous carcinoma cells OSC-19 invade collectively in the direction of the gradient of FBS. This invasion is more directional and aggressive than that observed for individual cells in the same experimental setup. In contrast to spheroids of OSC-19, U87-MG multicellular spheroids migrate as individual cells. A study of the exposure of spheroids to the chemoattractant shows that the rate of diffusion into the spheroid is slow and thus, the chemoattractant wave engulfs the spheroid before diffusing through it.
- Published
- 2015
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16. Impact of INICC Multidimensional Hand Hygiene Approach in ICUs in Four Cities in Argentina.
- Author
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Rosenthal VD, Viegas M, Sztokhamer D, Benchetrit G, Santoro B, Lastra CE, Romani A, Di Núbila BM, Lanzetta D, Fernández LJ, Rossetti MA, Migazzi C, Barolin C, Martínez E, Bonaventura C, Caridi Mde L, Messina A, Ricci B, Soroka LC, and Frías ML
- Subjects
- Argentina, Cross Infection prevention & control, Female, Health Personnel education, Health Personnel standards, Humans, Infection Control standards, Male, Prospective Studies, Quality Improvement, Sex Factors, Guideline Adherence, Hand Hygiene standards, Intensive Care Units
- Abstract
We evaluated the impact of the International Nosocomial Infection Control Consortium multidimensional approach to hand hygiene in 11 intensive care units in 4 cities in Argentina and analyzed predictors of poor hand hygiene compliance. We had a baseline period and a follow-up period. We observed 21 100 hand hygiene opportunities. Hand hygiene compliance increased from 28.3% to 64.8% (P = .0001). Males versus females (56.8% vs 66.4%; P < .001) and physicians versus nurses (46.6% vs 67.8%; P < .001) were significantly associated with poor hand hygiene compliance.
- Published
- 2015
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17. [Paget-Schroetter syndrome].
- Author
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Botas Velasco M, Calvín Álvarez P, Vaquero Lorenzo F, Álvarez Salgado A, and Álvarez Fernández LJ
- Subjects
- Female, Humans, Middle Aged, Upper Extremity Deep Vein Thrombosis diagnosis, Upper Extremity Deep Vein Thrombosis therapy
- Published
- 2013
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18. SU-8 based microprobes for simultaneous neural depth recording and drug delivery in the brain.
- Author
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Altuna A, Bellistri E, Cid E, Aivar P, Gal B, Berganzo J, Gabriel G, Guimerà A, Villa R, Fernández LJ, and Menendez de la Prida L
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- Animals, Brain cytology, Neurons cytology, Rats, Time Factors, Brain physiology, Drug Carriers metabolism, Electrophysiological Phenomena, Epoxy Compounds metabolism, Microtechnology methods, Molecular Probes metabolism, Polymers metabolism
- Abstract
While novel influential concepts in neuroscience bring the focus to local activities generated within a few tens of cubic micrometers in the brain, we are still devoid of appropriate tools to record and manipulate pharmacologically neuronal activity at this fine scale. Here we designed, fabricated and encapsulated microprobes for simultaneous depth recording and drug delivery using exclusively the polymer SU-8 as structural material. A tetrode- and linear-like electrode patterning was combined for the first time with single and double fluidic microchannels for independent drug delivery. The device was tested experimentally using the in vivo anesthetized rat preparation. Both probe types successfully recorded detailed spatiotemporal features of local field potentials and single-cell activity at a resolution never attained before with integrated fluidic probes. Drug delivery was achieved with high spatial and temporal precision in a range from tens of nanoliters to a few microliters, as confirmed histologically. These technological advancements will foster a wide range of neural applications aimed at simultaneous monitoring of brain activity and delivery at a very precise micrometer scale.
- Published
- 2013
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19. Design and fabrication of a COP-based microfluidic chip: chronoamperometric detection of Troponin T.
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Abad L, Javier del Campo F, Muñoz FX, Fernández LJ, Calavia D, Colom G, Salvador JP, Marco MP, Escamilla-Gómez V, Esteban-Fernández de Ávila B, Campuzano S, Pedrero M, Pingarrón JM, Godino N, Gorkin R 3rd, and Ducrée J
- Subjects
- Antibodies, Immobilized chemistry, Antibodies, Immobilized metabolism, Calibration, Cycloparaffins chemistry, Electrochemical Techniques methods, Equipment Design, Humans, Immunomagnetic Separation instrumentation, Immunomagnetic Separation methods, Limit of Detection, Microfluidic Analytical Techniques methods, Polymers chemistry, Electrochemical Techniques instrumentation, Microfluidic Analytical Techniques instrumentation, Troponin T analysis, Troponin T blood
- Abstract
This work demonstrates the design and fabrication of an all cyclo-olefin polymer based microfluidic device capable of capturing magnetic beads and performing electrochemical detection in a series of gold electrodes. The size of chip is of a microscope slide and features six independent measuring cells for multianalyte detection purposes. The aim of this work is to show that rapid prototyping techniques can be instrumental in the development of novel bioassays, particularly in clinical diagnosis applications. We show the successful determination of troponin-T, a cardiac disease marker, in the clinically relevant range of 0.05-1.0 ng/mL. This methodology achieves a detection limit of 0.017 ng/mL in PBS solutions, and is capable of detecting less than 1 ng/mL in a 1:50 human serum dilution., (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2012
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20. SU-8 based microprobes with integrated planar electrodes for enhanced neural depth recording.
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Altuna A, Menendez de la Prida L, Bellistri E, Gabriel G, Guimerá A, Berganzo J, Villa R, and Fernández LJ
- Subjects
- Action Potentials, Animals, Dielectric Spectroscopy, Equipment Design, Hippocampus cytology, Rats, Epoxy Compounds chemistry, Microelectrodes, Microtechnology methods, Neurons physiology, Polymers chemistry
- Abstract
Here, we describe new fabrication methods aimed to integrate planar tetrode-like electrodes into a polymer SU-8 based microprobe for neuronal recording applications. New concepts on the fabrication sequences are introduced in order to eliminate the typical electrode-tissue gap associated to the passivation layer. Optimization of the photolithography technique and high step coverage of the sputtering process have been critical steps in this new fabrication process. Impedance characterization confirmed the viability of the electrodes for reliable neuronal recordings with values comparable to commercial probes. Furthermore, a homogeneous sensing behavior was obtained in all the electrodes of each probe. Finally, in vivo action potential and local field potential recordings were successfully obtained from the rat dorsal hippocampus. Peak-to-peak amplitude of action potentials ranged from noise level to up to 400-500 μV. Moreover, action potentials of different amplitudes and shapes were recorded from all the four recording sites, suggesting improved capability of the tetrode to distinguish from different neuronal sources., (Copyright © 2012 Elsevier B.V. All rights reserved.)
- Published
- 2012
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21. Nanophotonic lab-on-a-chip platforms including novel bimodal interferometers, microfluidics and grating couplers.
- Author
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Duval D, González-Guerrero AB, Dante S, Osmond J, Monge R, Fernández LJ, Zinoviev KE, Domínguez C, and Lechuga LM
- Subjects
- Antibodies immunology, Biosensing Techniques, Humans, Interferometry methods, Microfluidic Analytical Techniques methods, Nanotechnology methods, Optics and Photonics methods, Refractometry, Thyrotropin analysis, Thyrotropin immunology, Interferometry instrumentation, Lab-On-A-Chip Devices, Microfluidic Analytical Techniques instrumentation, Nanotechnology instrumentation, Optics and Photonics instrumentation
- Abstract
One of the main limitations for achieving truly lab-on-a-chip (LOC) devices for point-of-care diagnosis is the incorporation of the "on-chip" detection. Indeed, most of the state-of-the-art LOC devices usually require complex read-out instrumentation, losing the main advantages of portability and simplicity. In this context, we present our last advances towards the achievement of a portable and label-free LOC platform with highly sensitive "on-chip" detection by using nanophotonic biosensors. Bimodal waveguide interferometers fabricated by standard silicon processes have been integrated with sub-micronic grating couplers for efficient light in-coupling, showing a phase resolution of 6.6 × 10(-4)× 2π rad and a limit of detection of 3.3 × 10(-7) refractive index unit (RIU) in bulk. A 3D network of SU-8 polymer microfluidics monolithically assembled at the wafer-level was included, ensuring perfect sealing and compact packaging. To overcome some of the drawbacks inherent to interferometric read-outs, a novel all-optical wavelength modulation system has been implemented, providing a linear response and a direct read-out of the phase variation. Sensitivity, specificity and reproducibility of the wavelength modulated BiMW sensor has been demonstrated through the label-free immunodetection of the human hormone hTSH at picomolar level using a reliable biofunctionalization process.
- Published
- 2012
- Full Text
- View/download PDF
22. SU8 diaphragm micropump with monolithically integrated cantilever check valves.
- Author
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Ezkerra A, Fernández LJ, Mayora K, and Ruano-López JM
- Subjects
- Dimethylpolysiloxanes chemistry, Equipment Design, Lab-On-A-Chip Devices, Microfluidic Analytical Techniques methods, Microfluidic Analytical Techniques instrumentation
- Abstract
This paper presents a SU8 unidirectional diaphragm micropump with embedded out-of-plane cantilever check valves. The device represents a reliable and low-cost solution for integration of microfluidic control in lab-on-a-chip devices. Its planar architecture allows monolithic definition of its components in a single step and potential integration with previously reported PCR, electrophoresis and flow-sensing SU8 microdevices. Pneumatic actuation is applied on a PDMS diaphragm, which is bonded to the SU8 body at wafer level, further enhancing its integration and mass production capabilities. The cantilever check valves move synchronously with the diaphragm, feature fast response (10ms), low dead volume (86nl) and a 94% flow blockage up to 300kPa. The micropump achieves a maximum flow rate of 177 μl min(-1) at 6 Hz and 200 kPa with an effective area of 10 mm(2). The device is reliable, self-priming and tolerant to particles and big bubbles. To the knowledge of the authors, this is the first micropump in SU8 with monolithically integrated cantilever check valves.
- Published
- 2011
- Full Text
- View/download PDF
23. [Malignant fibrous histiocytoma as degeneration of a venous ulcer].
- Author
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Alvarez Salgado A, Vaquero Lorenzo F, Vicente Santiago M, Ramos Gallo MJ, and Alvarez Fernández LJ
- Subjects
- Aged, Disease Progression, Histiocytoma, Malignant Fibrous surgery, Humans, Magnetic Resonance Imaging, Male, Prognosis, Soft Tissue Neoplasms surgery, Varicose Ulcer surgery, Histiocytoma, Malignant Fibrous pathology, Soft Tissue Neoplasms pathology, Varicose Ulcer pathology
- Published
- 2010
- Full Text
- View/download PDF
24. Fabrication of SU-8 based microchip electrophoresis with integrated electrochemical detection for neurotransmitters.
- Author
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Castaño-Alvarez M, Fernández-Abedul MT, Costa-García A, Agirregabiria M, Fernández LJ, Ruano-López JM, and Barredo-Presa B
- Subjects
- Dopamine analysis, Electrochemistry instrumentation, Electrophoresis, Capillary, Electrophoresis, Microchip instrumentation, Epinephrine analysis, Reproducibility of Results, Electrochemistry methods, Electrophoresis, Microchip methods, Neurotransmitter Agents analysis
- Abstract
A new SU-8 based microchip capillary electrophoresis (MCE) device has been developed for the first time with integrated electrochemical detection. Embedded electrophoretic microchannels have been fabricated with a multilayer technology based on bonding and releasing steps of stacked SU-8 films. This technology has allowed the monolithic integration in the device of the electrochemical detection system based on platinum electrodes. The fabrication of the chips presented in this work is totally compatible with reel-to-reel techniques, which guarantee a low cost and high reliability production. The influence of relevant experimental variables, such as the separation voltage and detection potential, has been studied on the SU-8 microchip with an attractive analytical performance. Thus, the effective electrical isolation of the end-channel amperometric detector has been also demonstrated. The good performance of the SU-8 device has been proven for separation and detection of the neurotransmitters, dopamine (DA) and epinephrine (EP). High efficiency (30,000-80,000 N/m), excellent precision, good detection limit (450 nM) and resolution (0.90-1.30) has been achieved on the SU-8 microchip. These SU-8 devices have shown a better performance than commercial Topas (thermoplastic olefin polymer of amorphous structure) microchips. The low cost and versatile SU-8 microchip with integrated platinum film electrochemical detector holds great promise for high-volume production of disposable microfluidic analytical devices.
- Published
- 2009
- Full Text
- View/download PDF
25. [Implications of the REACH registry for vascular surgery].
- Author
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Alvarez-Fernández LJ, Vallina-Victorero Vázquez MJ, Ramos Gallo MJ, and Santiago MV
- Subjects
- Aged, Female, Humans, Male, Vascular Diseases complications, Atherosclerosis prevention & control, Myocardial Infarction prevention & control, Registries, Stroke prevention & control, Thrombosis prevention & control, Vascular Diseases surgery, Vascular Surgical Procedures
- Abstract
Because of the increase in life expectancy, peripheral artery disease (PAD) has become a major health problem. A study performed in Spain in persons aged more than 65 years old found an overall prevalence of PAD of 9.9%. The most important risk factors for PAD were smoking, diabetes mellitus, advanced age, hyperlipidemia and hypertension. Treatment includes smoking cessation, exercise, statins, platelet antiaggregants, cilostazol or hemorheologic agents, and revascularization techniques. Data from the Spanish arm of REACH indicate that the PAD subgroup shows the poorest control of blood pressure and cholesterol and that use of platelet antiaggregants and statins is lowest in these patients, indicating that therapeutic and preventive strategies are not being correctly applied.
- Published
- 2009
- Full Text
- View/download PDF
26. SU-8 microprobe with microelectrodes for monitoring electrical impedance in living tissues.
- Author
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Tijero M, Gabriel G, Caro J, Altuna A, Hernández R, Villa R, Berganzo J, Blanco FJ, Salido R, and Fernández LJ
- Subjects
- Equipment Design, Equipment Failure Analysis, Ischemia physiopathology, Kidney physiopathology, Miniaturization, Plethysmography, Impedance methods, Reproducibility of Results, Sensitivity and Specificity, Biosensing Techniques instrumentation, Epoxy Compounds chemistry, Ischemia diagnosis, Kidney blood supply, Microelectrodes, Needles, Plethysmography, Impedance instrumentation, Polymers chemistry, Transducers
- Abstract
This paper presents a minimally invasive needle-shaped probe capable of monitoring the electrical impedance of living tissues. This microprobe consists of a 160 microm thick SU-8 substrate containing four planar platinum (Pt) microelectrodes. We design the probe to minimize damage to the surrounding tissue and to be stiff enough to be inserted in living tissues. The proposed batch fabrication process is low cost and low time consuming. The microelectrodes obtained with this process are strongly adhered to the SU-8 substrate and their impedance does not depend on frequency variation. In vitro experiments are compared with previously developed Si and SiC based microprobes and results suggest that it is preferable to use the SU-8 based microprobes due to their flexibility and low cost. The microprobe is assembled on a flexible printed circuit FPC with a conductive glue, packaged with epoxy and wired to the external instrumentation. This flexible probe is inserted into a rat kidney without fracturing and succeeds in demonstrating the ischemia monitoring.
- Published
- 2009
- Full Text
- View/download PDF
27. [Eating disorders].
- Author
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Aguinaga M, Fernández LJ, and Varo J
- Abstract
At the present time, research into Eating Disorders is being carried out in very different areas: clinical and diagnostic, epidemiological, comorbidity, aetiopathogeny, treatment and forms of care. This paper reviews this type of pathology, and aims to update the most important data in the different fields. The epidemiological studies of recent decades would indicate a considerable increase in the rates of incidence and prevalence of both Nervous Anorexia and Nervous Bulimia. On the other hand, there is increasing confirmation of an early appearance of these disorders. Similarly, the discovery of certain physiopathological appetite markers and/or regulators opens a new path for understanding this phenomenon. Research into these problems has reached a certain consensus in aspects such as: a multidimensional consideration of the ethiopathogeny, increasingly purified diagnostic criteria, care and therapeutic procedures and resources to be used in treatment.
- Published
- 2000
- Full Text
- View/download PDF
28. [Pulsatile perineal hematoma after transrectal prostatic biopsy].
- Author
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Vallina Vázquez MJ, Gutiérrez Julián JM, Vega Gutiérrez F, Suárez Hevia M, Carreño Morrondo A, Fernández Solares I, Menéndez Herrero MA, Llaneza Coto JM, Rodríguez Olay J, and Alvarez Fernández LJ
- Subjects
- Humans, Male, Middle Aged, Biopsy adverse effects, Hematoma etiology, Perineum
- Abstract
Objective: A case of pulsatile perineal hematoma following transrectal biopsy of the prostate is presented., Methods: A patient who had undergone transrectal biopsy of the prostate a few days earlier complained of a pulsatile sensation in the perineal region caused by a pseudoaneurysm of a left hypogastric artery. Patient evaluation included echo Doppler, pelvioabdominal CT and arteriography. Transcatheter intraarterial embolization with Gianturco-Wallace coils was performed., Results: Excellent results were achieved. Filling of the aneurysm was immediately reduced and symptoms disappeared., Conclusion: This technique is gaining importance in the treatment of pelvic hemorrhage because it is relatively simple and carries a low morbidity and mortality.
- Published
- 1999
29. [Legal disability in patients with mental disorders].
- Author
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Terrer M, Molins J, and Fernández LJ
- Abstract
This article offers an approach to the present juridical situation of the processes of occupational incapacity - in the contributive and non-contributive types - for patients with psychological disorders, taking into account the wide range of nuances that this implies. Finally, some verdicts of the Spanish Superior Court of Justice are added, in order to illustrate the present situation about the jurisprudence referring to permanent contributive incapacity.
- Published
- 1999
- Full Text
- View/download PDF
30. [Extraction of senile cataract by means of suction].
- Author
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Fernández LJ
- Subjects
- Aged, Humans, Suction, Cataract Extraction methods
- Published
- 1989
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