24 results on '"Varela AI"'
Search Results
2. Seabirds as biovectors in the transport of plastic debris across ecosystem borders: A case study from the Humboldt Current Upwelling System.
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Fernández CE, Luna-Jorquera G, González Encinas V, Auger Lancelloti A, Lantadilla C, Aguilar-Pulido R, Kiessling T, Knickmeier K, Varela AI, and Thiel M
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- Animals, Chile, Charadriiformes physiology, Waste Products analysis, Water Pollutants, Chemical analysis, Microplastics analysis, Plastics analysis, Environmental Monitoring, Ecosystem, Birds
- Abstract
Seabirds have become biovectors of plastic pollutants between marine and terrestrial ecosystems, and transport of plastics to their nesting sites becomes relevant due to increasing levels of pollution. To determine the pathways by which plastic reaches their colonies, we analysed the abundance of plastics at the nesting sites of five seabird species (Humboldt penguin Spheniscus humboldti, Peruvian booby Sula variegata, kelp gull Larus dominicanus, grey gull Leucophaeus modestus, Markham's storm-petrel Hydrobates markhami) nesting in northern Chile. Seabirds were primarily grouped according to their nesting behaviour, but two species foraging in contrasting habitats (kelp gull and Markham's storm-petrel) were also compared directly. The abundance, type, and polymer of macro-, meso- and microplastics were analysed in the soil of colonies and control sites, and microplastic ingestion was evaluated for selected species. Densities of plastics in colonies of surface-nesting seabirds ranged from 0 to 21.4 items m
-2 (mainly plastic bags and thin films), and 0.002 to 19.7 items m-2 (mainly hard fragments) in colonies of burrow-nesting seabirds. Mean microplastic loads in the stomachs of seabirds were between 3.7 ± 4.2 plastic items individual-1 . Overall, the abundances of plastic items in all seabird colonies were low, suggesting a limited transfer of plastics from sea to land. For kelp gulls, the results indicate transfer of macroplastic items to colonies, reaching the colony via regurgitates, with landfills considered as the main plastic source. Our results suggest that contrasting nesting behaviour and foraging habitats among species can explain differential plastic accumulation in seabird colonies, but also other factors, such as wind, contribute to the accumulation of plastic debris in colonies. Proper management of sanitary landfills are key to reduce plastic contamination of coastal seabirds and their colonies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
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3. Biocompatibility Testing of UV-Curable Polydimethylsiloxane for Human Umbilical Vein Endothelial Cell Culture on-a-Chip.
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Gómez-Varela AI, Viña A, Bao-Varela C, Flores-Arias MT, Carnero B, González-Peteiro M, González-Juanatey JR, and Álvarez E
- Abstract
Polydimethylsiloxane (PDMS) is extensively used to fabricate biocompatible microfluidic systems due to its favorable properties for cell culture. Recently, ultraviolet-curable PDMS (UV-PDMS) has shown potential for enhancing manufacturing processes and final optical quality while retaining the benefits of traditional thermally cured PDMS. This study investigates the biocompatibility of UV-PDMS under static and flow conditions using human umbilical vein endothelial cells (HUVECs). UV-PDMS samples were treated with oxygen plasma and boiling deionized water to assess potential improvements in cell behavior compared with untreated samples. We evaluated HUVECs adhesion, growth, morphology, and viability in static cultures and microchannels fabricated with UV-PDMS to test their resistance to flow conditions. Our results confirmed the biocompatibility of UV-PDMS for HUVECs culture. Moreover, plasma-oxygen-treated UV-PDMS substrates exhibited superior cell growth and adhesion compared to untreated UV-PDMS. This enhancement enabled HUVECs to maintain their morphology and viability under flow conditions in UV-PDMS microchannels. Additionally, UV-PDMS demonstrated improved optical quality and more efficient handling and processing, characterized by shorter curing times and simplified procedures utilizing UV light compared to traditional PDMS., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)
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- 2024
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4. Photosensitive Control and Network Synchronization of Chemical Oscillators.
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Carballosa A, Gomez-Varela AI, Bao-Varela C, Flores-Arias MT, and Muñuzuri AP
- Abstract
The Belousov-Zhabotinsky (BZ) reaction has long been a paradigmatic system for studying chemical oscillations. Here, we experimentally studied the synchronization control within photochemically coupled star networks of BZ oscillators. Experiments were carried out in wells performed in soda-lime glass constructed using novel laser technologies. Utilizing the inherent oscillatory nature of the BZ reaction, we engineered a star network of oscillators interconnected through photochemical inhibitory coupling. Furthermore, the experimental setup presented here could be extrapolated to more complex network architectures with both excitatory and inhibitory couplings, contributing to the fundamental understanding of synchronization in complex systems.
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- 2024
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5. Are artificial intelligence chatbots a reliable source of information about contact lenses?
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García-Porta N, Vaughan M, Rendo-González S, Gómez-Varela AI, O'Donnell A, de-Moura J, Novo-Bujan J, and Ortega-Hortas M
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- Humans, Artificial Intelligence, Language, Information Sources, Contact Lenses, Optometrists
- Abstract
Introduction: Artificial Intelligence (AI) chatbots are able to explain complex concepts using plain language. The aim of this study was to assess the accuracy of three AI chatbots answering common questions related to contact lens (CL) wear., Methods: Three open access AI chatbots were compared: Perplexity, Open Assistant and ChatGPT 3.5. Ten general CL questions were asked to all AI chatbots on the same day in two different countries, with the questions asked in Spanish from Spain and in English from the U.K. Two independent optometrists with experience working in each country assessed the accuracy of the answers provided. Also, the AI chatbots' responses were assessed if their outputs showed any bias towards (or against) any eye care professional (ECP)., Results: The answers obtained by the same AI chatbots were different in Spain and the U.K. Also, statistically significant differences were found between the AI chatbots for accuracy. In the U.K., ChatGPT 3.5 was the most and Open Assistant least accurate (p < 0.01). In Spain, Perplexity and ChatGPT were statistically more accurate than Open Assistant (p < 0.01). All the AI chatbots presented bias, except ChatGPT 3.5 in Spain., Conclusions: AI chatbots do not always consider local CL legislation, and their accuracy seems to be dependent on the language used to interact with them. Hence, at this time, although some AI chatbots might be a good source of information for general CL related questions, they cannot replace an ECP., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)
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- 2024
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6. Long-Term Follow-Up in Patients With Chronic Myeloid Leukemia Treated With Ponatinib in a Real-World Cohort: Safety and Efficacy Analysis.
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Mela Osorio MJ, Moiraghi B, Osycka MV, Pavlovsky MA, Varela AI, Bendek Del Prete GE, Tosin MF, Pérez MA, Riva ME, Berrios RR, Fernández I, Sackmann Massa F, Giere I, Sighel C, and Pavlovsky C
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- Humans, Male, Adult, Follow-Up Studies, Retrospective Studies, Blast Crisis drug therapy, Fusion Proteins, bcr-abl genetics, Protein Kinase Inhibitors adverse effects, Antineoplastic Agents therapeutic use, Leukemia, Myelogenous, Chronic, BCR-ABL Positive drug therapy, Leukemia, Myelogenous, Chronic, BCR-ABL Positive genetics, Pyridazines adverse effects, Imidazoles
- Abstract
Background: Ponatinib is a third-generation tyrosine-kinase inhibitor (TKI), indicated in patients with chronic phase (CP), accelerated phase (AP), or blast phase (BP) chronic myeloid leukemia (CML), who are resistant or intolerant to ≥2 prior TKIs, patients for whom subsequent treatment with imatinib is not appropriate, and patients who have a T315I mutation., Patients and Methods: We aimed to evaluate outcomes of ponatinib treatment, including safety, with focus on cardiovascular toxicity, in real-world patients from Argentina. Data from patients with CP CML treated with ponatinib was retrospectively retrieved from 2013 to 2023 in 7 centers., Results: Seventy-two patients were included (median age: 44 years; male: 55.5%; T315I mutation: 32%: median treatment duration: 36 months. At baseline, 57 patients (79%) had a breakpoint cluster region-Abelson (BCR::ABL1) transcript level >10% on the international reporting scale (BCR::ABL1 IS). A molecular response (MR, BCR::ABL1 (IS) <1%) was achieved at 12 months in 51.6% of evaluable patients; 57% maintained MR at last follow-up. Overall, 43% and 25% maintained major MR (MMR) or deep MR (DMR) (MR4.0-MR5.0), respectively at last follow-up. Twelve (16.6%) ponatinib-resistant patients were rescued with allogeneic hematopoietic stem cell transplantation. The estimated 2-year progression-free survival (PFS) was 84%. Ponatinib dose was reduced during treatment in 22 patients; nevertheless, MMR was maintained in 50% of these patients. Severe arterial occlusive events (AOE) were reported in 10.9% of patients after a median treatment of 5 months., Conclusion: CV toxicity was consistent with clinical trials and other real-world registries. Older age, hypercholesterolemia and a SCORE risk >2% were significantly associated with higher risk of AOEs. Controlling CV risk factors and reducing doses at optimal time points may help to optimize ponatinib use in daily practice., Competing Interests: Disclosure The authors have stated that they have no conflicts of interest., (Copyright © 2023. Published by Elsevier Inc.)
- Published
- 2024
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7. Visual performance of new affordable and auto-adherent lenses for presbyopia correction.
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Garcia-Porta N, Gómez-Varela AI, and Arines-Piferrer J
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- Humans, Visual Acuity, Vision, Ocular, Contrast Sensitivity, Presbyopia therapy, Population Health
- Abstract
Presbyopia is a visual condition that affects all of us, evolving with time, reducing the range of accommodation and the ability to work at near. Reading glasses, bifocals or multifocal lenses are the most common solutions. In this work, we demonstrate the near visual performance of new elastomeric auto-adherent lenses developed for the correction of presbyopia. Visual acuity and contrast sensitivity were measured in 10 presbyopic subjects. The results showed that wearing either conventional trial ophthalmic lenses or the new elastomeric lenses provided similar visual quality. These elastomeric lenses can be placed in, or removed from the distance-vision spectacles of the wearers, providing an affordable solution for correcting presbyopia at its clinical onset, which might be especially useful in subjects with different refractive error in each eye and for those with astigmatism., (© 2023 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.)
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- 2024
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8. [Bacterial coinfection in the critically-ill COVID-19 patient: incidence, impact and need for antimicrobial therapy].
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Vidal-Cortés P, Nieto Del Olmo J, Tizón Varela AI, Seoane Fernández E, Eiras Abalde F, Blanco Chapela J, Larrañaga Sigwald L, Suárez Fernández DE, Fernández Ugidos P, and Del Río Carbajo L
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- Humans, SARS-CoV-2, Critical Illness, Retrospective Studies, Incidence, Intensive Care Units, COVID-19 complications, COVID-19 epidemiology, Coinfection drug therapy, Coinfection epidemiology, Anti-Infective Agents
- Abstract
Objective: To assess the frequency of bacterial coinfection upon ICU admission in SARS-CoV-2 pneumonia patients, its microbiology, and impact on prognosis.The secondary objective was to identify risk factors for coinfection on admission., Methods: Retrospective study, including patients with SARS-CoV-2 pneumonia admitted to the ICU.We defined bacterial coinfection by respiratory symptoms, radiological data, positive and clinically significant microbiological results in samples obtained in the first 48 h of admission and/or a determination of procalcitonin ≥ 0.5 ng/mL in the first 48 h.We evaluated demographic variables, comorbidities, SARS-CoV-2 infection data, severity scores, treatments received, need for respiratory support and outcomes (ICU and hospital mortality)., Results: A total of 182 patients were analyzed, 62 (34.1%) with bacterial coinfection.The most frequent microbiology was S. pneumoniae and M. pneumoniae. 96.1% of the patients received antibiotic therapy on admission, 98.9% corticosteroids, 27.5% tocilizumab, and 7.7% remdesivir.85.7% required invasive mechanical ventilation.The SOFA score (OR: 1.315, 95% CI1.116-1.548) and the delay in ICU admission (OR: 0.899, 95% CI 0.831-0.972) were related to the risk of coinfection. Bacterial coinfection increases the risk of death in hospital (OR 2.283; 95% CI 1.011.5.151; p=0.047)., Conclusions: Bacterial coinfection is common in COVID patients admitted to the ICU and increases the risk of death. It is not possible to identify with certainty, at the time of admission, which patients do not benefit from antibiotic treatment., (©The Author 2023. Published by Sociedad Española de Quimioterapia. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)(https://creativecommons.org/licenses/by-nc/4.0/).)
- Published
- 2023
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9. [Macrolide-resistant Mycoplasma pneumoniae: Do we know the situation in Europe?]
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Álvaro Varela AI, Aguinaga Pérez A, Navascués Ortega A, Castilla Catalán J, and Ezpeleta Baquedano C
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- Humans, Macrolides pharmacology, Macrolides therapeutic use, Drug Resistance, Bacterial, Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents therapeutic use, Europe epidemiology, Mycoplasma pneumoniae genetics, Pneumonia, Mycoplasma drug therapy, Pneumonia, Mycoplasma epidemiology, Pneumonia, Mycoplasma diagnosis
- Abstract
Mycoplasma pneumoniae is a bacterium that lacks a cell wall. It produces infections all It produces infections world-wide, in epidemic outbreaks every 4-7 years, or endemically. Its clinical manifestations occur mostly in the respiratory tract and it is a common cause of atypical pneumonia. The treatment is with macrolides, tetracyclines or fluoroquinolones. Since 2000, an increase in resistance to macrolides has been detected worldwide, being more frequent in Asia. In Europe the frequency of resistance ranges between 1% and 25%, depending on the country. Molecular techniques and serology techniques provides very high sensitivity in diagnostic confirmation, being very useful for detecting and controlling M. pneumoniae outbreaks. The detection of resistance to macrolides requires a sequencing technique., (©The Author 2023. Published by Sociedad Española de Quimioterapia. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)(https://creativecommons.org/licenses/by-nc/4.0/).)
- Published
- 2023
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10. Subaquatic indirect laser ablation technique for glass processing.
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Gómez-Varela AI, Sanchez R, Carnero B, Diaz-Gomez L, Flores-Arias MT, and Bao-Varela C
- Abstract
Subaquatic indirect Laser-Induced Plasma-Assisted Ablation (SLIPAA) is proposed as a laser-based technique for glass processing. In this configuration, a water layer is added between a metallic target and a soda-lime glass substrate, so the processing of the glass is due to a combination of the ablation mechanism, the shock waves, and the cavitation bubbles. Thus, this method makes it possible to produce higher depth structures than those performed up to now by other standard laser techniques based on ablation, achieving structures in glass with rectangular cross-sectional profiles. Channels of 1 mm width are fabricated, reaching an average maximal depth value of almost 1400 µm at 30 passes of the laser beam while keeping the focal position fixed. Furthermore, the difference between processing the material with and without the addition of the water layer is presented. The influence of the processing parameters on the shape and quality of the fabricated structures is studied by optical and confocal microscopy, microcomputed tomography, and scanning electron microscopy. Compositional analysis of the glass is performed by energy dispersive X-ray technique to assess the transference of material from the metallic target to the fabricated channels. Deeper and more complex structures are obtained by refocusing the laser beam on the target and adding a pulsed flowing water film.
- Published
- 2022
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11. Clinical characteristics of patients with Mycoplasma pneumoniae infection.
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Álvaro Varela AI, Aguinaga Pérez A, Navascués Ortega A, Castilla J, and Ezpeleta Baquedano C
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- Adolescent, Anti-Bacterial Agents therapeutic use, Child, Child, Preschool, Humans, Macrolides therapeutic use, Mycoplasma pneumoniae, Retrospective Studies, Community-Acquired Infections drug therapy, Pneumonia, Mycoplasma complications, Pneumonia, Mycoplasma drug therapy, Pneumonia, Mycoplasma epidemiology
- Abstract
Objective: To describe the characteristics of patients diagnosed with Mycoplasma pneumoniae infection., Methods: A retrospective study of clinical and epidemiological characteristics of acute infections by M. pneumoniae confirmed by PCR was carried out in the Navarra Health Service (Spain) in 2014-2018., Results: M. pneumoniae infection was confirmed in 9.5% of analyzed patients. Among 123 confirmed cases, 65% were 5-14 years old, 21.1% <5 years old, and 13.8% were ≥14 years old. Pneumonia was radiologically confirmed in 83.7% of cases, and 22.0% presented extra-respiratory manifestations. A total of 44.7% of cases required hospitalization. Bilateral pneumonia, asthmatic crisis and extra-respiratory manifestations were associated to higher risk of hospitalization (81.3, 72.2 and 66.7%, respectively). Microbiological targeted treatment was monotherapy with macrolides in 60.2% of cases and combined with other antibiotics in 13.0%., Conclusion: M. pneumoniae was the cause of acute respiratory infection affecting mainly to children younger than 14 years old and frequently required hospitalization., (Copyright © 2021 Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. Published by Elsevier España, S.L.U. All rights reserved.)
- Published
- 2022
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12. Treatment-free remission in patients with chronic myeloid leukemia: recommendations of the LALNET expert panel.
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Pavlovsky C, Abello Polo V, Pagnano K, Varela AI, Agudelo C, Bianchini M, Boquimpani C, Centrone R, Conchon M, Delgado N, Funke V, Giere I, Luise I, Meillon L, Moiraghi B, Navarro JR, Pilleux L, Prado AI, Undurraga S, and Cortes J
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- Humans, Polymerase Chain Reaction, Recurrence, Remission Induction, Leukemia, Myelogenous, Chronic, BCR-ABL Positive drug therapy, Leukemia, Myelogenous, Chronic, BCR-ABL Positive genetics, Protein Kinase Inhibitors therapeutic use
- Abstract
Tyrosine kinase inhibitors (TKIs) have dramatically changed the survival of chronic myeloid leukemia (CML) patients, and treatment-free remission (TFR) has recently emerged as a new goal of CML treatment. The aim of this work was to develop recommendations for TKI discontinuation in Latin America (LA), outside of clinical trials. A working group of CML experts from LA discussed 22 questions regarding TFR and reached a consensus for TFR recommendations in the region. TFR is indicated in patients in first chronic phase, with typical BCR-ABL transcripts, under TKI treatment of a minimum of 5 years, in sustained deep molecular response (DMR; molecular response 4.5 [MR4.5]) for 2 years. Sustained DMR must be demonstrated on at least 4 international reporting scale quantitative polymerase chain reaction (PCR) tests, separated by at least 3 months, in the immediate prior 2 years. After second-line therapy, TFR is indicated in previously intolerant, not resistant, patients. Molecular monitoring is recommended monthly for the first 6 months, every 2 to 3 months from months 7 to 12, and every 3 months during the second year, indefinitely. Treatment should be reintroduced if major molecular response is lost. Monitoring of withdrawal syndrome, glucose levels, and lipid profile is recommended after discontinuation. After TKI reintroduction, molecular monitoring is indicated every 2 to 3 months until MR4.0 achievement; later, every 3 to 6 months. For the TFR attempt, having standardized and reliable BCR-ABL PCR tests is mandatory. These recommendations will be useful for safe discontinuation in daily practice and will benefit patients who wish to stop treatment in emergent regions, in particular, with TKI-related chronic adverse events., (© 2021 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)
- Published
- 2021
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13. Microfluidic devices manufacturing with a stereolithographic printer for biological applications.
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Carnero B, Bao-Varela C, Gómez-Varela AI, Álvarez E, and Flores-Arias MT
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- Human Umbilical Vein Endothelial Cells, Humans, Microfluidics, Stereolithography, Lab-On-A-Chip Devices, Printing, Three-Dimensional
- Abstract
Stereolithographic printers have revolutionized many manufacturing processes with their capacity to easily produce highly detailed structures. In the field of microfluidics, this technique avoids the use of complex steps and equipment of the conventional technologies. The potential of low force stereolithography technology is analysed for the first time using a Form 3B printer and seven printing resins through the fabrication of microchannels and pillars. Manufacturing performance of internal and superficial channels and pillars is studied for the seven printing resins in different configurations. A complete characterization of printed structures is carried out by optical, confocal and SEM microscopy, and EDX analysis. Internal channels with unobstructed lumen are obtained for diameters and angles greater than 500 μm and 60°, respectively. Outward and inward superficial channels in the range of hundreds of microns can be fabricated with an accurate profile, printing them with a perpendicular orientation respect to the base, allowing a proper uncured resin evacuation. Outward channels are replicated by soft lithography using polydimethylsiloxane. Clear, Model and Tough resins show a good behaviour to be used as master, but Amber and Dental resins present a poor topology transference from the master to the replica. According to the needs of devices used for biological and biomedical research, transparency as well as superficial biocompatibility of some resins is evaluated. Human umbilical vein endothelial cells (HUVEC) adhesion is confirmed on Amber, Dental and Clear resins, but these cells were only able to grow and progress as a cell culture over the Amber resin. Therefore, Amber showed an adequate biocompatibility, in terms of cell adhesion and growth for HUVEC., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2021
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14. Challenges in Chronic Myeloid Leukemia Management in South America.
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Pagnano KB, Varela AI, Pavlovsky C, Bendit I, Funke VAM, and Polo VA
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- Antineoplastic Agents therapeutic use, Disease Management, Hematopoietic Stem Cell Transplantation, Humans, Leukemia, Myelogenous, Chronic, BCR-ABL Positive epidemiology, Protein Kinase Inhibitors therapeutic use, South America epidemiology, Leukemia, Myelogenous, Chronic, BCR-ABL Positive therapy
- Abstract
Purpose of Review: Chronic myeloid leukemia (CML) management in developing countries has improved in the last years, but the availability of therapeutic resources, monitoring, reimbursement, and financial issues may be a challenge and interfere with the best practices and results of CML treatment. This review points out the main challenges in CML management in South America., Recent Findings: In this review, we describe the access to tyrosine kinase inhibitors and monitoring in different countries of South America. We also address the ongoing discontinuation trials, the progress, and limitations of hematopoietic stem cell transplantation in the last years. There are still many challenges for achieving the best outcomes for CML patients in South America. The continuous efforts to provide continuous education, access to tyrosine kinase inhibitors, and monitoring, providing reference centers for CML management and hematopoietic stem cell transplantation may improve patients' outcomes., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
- Published
- 2021
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15. How did correlative atomic force microscopy and super-resolution microscopy evolve in the quest for unravelling enigmas in biology?
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Miranda A, Gómez-Varela AI, Stylianou A, Hirvonen LM, Sánchez H, and De Beule PAA
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- Microscopy, Atomic Force, Microscopy, Fluorescence, Biology
- Abstract
With the invention of the Atomic Force Microscope (AFM) in 1986 and the subsequent developments in liquid imaging and cellular imaging it became possible to study the topography of cellular specimens under nearly physiological conditions with nanometric resolution. The application of AFM to biological research was further expanded with the technological advances in imaging modes where topographical data can be combined with nanomechanical measurements, offering the possibility to retrieve the biophysical properties of tissues, cells, fibrous components and biomolecules. Meanwhile, the quest for breaking the Abbe diffraction limit restricting microscopic resolution led to the development of super-resolution fluorescence microscopy techniques that brought the resolution of the light microscope comparable to the resolution obtained by AFM. The instrumental combination of AFM and optical microscopy techniques has evolved over the last decades from integration of AFM with bright-field and phase-contrast imaging techniques at first to correlative AFM and wide-field fluorescence systems and then further to the combination of AFM and fluorescence based super-resolution microscopy modalities. Motivated by the many developments made over the last decade, we provide here a review on AFM combined with super-resolution fluorescence microscopy techniques and how they can be applied for expanding our understanding of biological processes.
- Published
- 2021
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16. COVID-19 and Acute Respiratory Distress Syndrome. Impact of corticosteroid treatment and predictors of poor outcome.
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Vidal-Cortés P, Del Río-Carbajo L, Nieto-Del Olmo J, Prol-Silva E, Tizón-Varela AI, Rodríguez-Vázquez A, Rodríguez-Rodríguez P, Díaz-López MD, Fernández-Ugidos P, and Pérez-Veloso MA
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- Aged, COVID-19 metabolism, Female, Humans, Intensive Care Units, Longitudinal Studies, Male, Middle Aged, Oxygen Consumption physiology, Respiration, Artificial, Respiratory Distress Syndrome metabolism, Retrospective Studies, Secondary Care Centers, Spain, Time Factors, Treatment Outcome, Oxygen Consumption drug effects, Respiratory Distress Syndrome drug therapy, SARS-CoV-2, COVID-19 Drug Treatment
- Abstract
Objective: To assess the impact of corticosteroids on inflammatory and respiratory parameters of patients with COVID-19 and acute respiratory distress syndrome (ARDS)., Methods: Longitudinal, retrospective, observational study conducted in an ICU of a second level hospital. Adult patients with COVID-19 were included. Baseline characteristics, data on SARS-CoV-2 infection, treatment received, evolution of respiratory and inflammatory parameters, and ICU and hospital stay and mortality were analyzed., Results: A total of 27 patients were included, 63% men, median age: 68.4 (51.8, 72.2) years. All patients met ARDS criteria and received MV and corticosteroids. After corticosteroids treatment we observed a reduction in the O2 A-a gradient [day 0: 322 (249, 425); day 3: 169 (129.5, 239.5) p<0.001; day 5: 144 (127.5, 228.0) p<0.001; day 7: 192 (120, 261) p=0.002] and an increase in the pO2/FiO2 ratio on days 3 and 5, but not on day 7 [day 0: 129 (100, 168); day 3: 193 (140, 236) p=0.002; day 5: 183 (141, 255) p=0.004; day 7: 170 (116, 251) p=0.057]. CRP also decreased on days 3 and 5 and increased again on day 7 [day 0: 16 (8.6, 24); day 3: 3.4 (1.7, 10.2) p<0.001; day 5: 4.1 (1.4, 10.2) p<0.001; day 7: 13.5 (6.8, 17.3) p=0.063]. Persistence of moderate ARDS on day 7 was related to a greater risk of poor outcome (OR 6.417 [1.091-37.735], p=0.040)., Conclusions: Corticosteroids appears to reduce the inflammation and temporarily improve the oxygenation in COVID-19 and ARDS patients. Persistence of ARDS after 7 days treatment is a predictor of poor outcome., (©The Author 2020. Published by Sociedad Española de Quimioterapia. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)(https://creativecommons.org/licenses/by-nc/4.0/).)
- Published
- 2021
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17. miRNome profiling of LSC-enriched CD34 + CD38 - CD26 + fraction in Ph + CML-CP samples from Argentinean patients: a potential new pharmacogenomic tool.
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Ruiz MS, Sánchez MB, Bonecker S, Furtado C, Koile D, Yankilevich P, Cranco S, Custidiano MDR, Freitas J, Moiraghi B, Pérez MA, Pavlovsky C, Varela AI, Ventriglia V, Sánchez Ávalos JC, Larripa I, Zalcberg I, Mordoh J, Valent P, and Bianchini M
- Abstract
Chronic myeloid leukemia (CML) is a myeloid stem cell neoplasm characterized by an expansion of myeloid progenitor cells and the presence of BCR-ABL1 oncoprotein. Since the introduction of specific BCR-ABL1 tyrosine kinase inhibitors (TKI), overall survival has improved significantly. However, under long-term therapy patients may have residual disease that originates from TKI-resistant leukemic stem cells (LSC). In this work, we analyzed the miRNome of LSC-enriched CD34
+ CD38- CD26+ and normal hematopoietic stem cells (HSC) fractions obtained from the same chronic phase (CP) CML patients, and stem and progenitor cells obtained from healthy donors (HD) by next-generation sequencing. We detected a global decrease of microRNA levels in LSC-enriched CD34+ CD38- CD26+ and HSC fractions from CML-CP patients, and decreased levels of microRNAs and snoRNAs from a genomic cluster in chromosome 14, suggesting a mechanism of silencing of multiple non-coding RNAs. Surprisingly, HSC from CML-CP patients, despite the absence of BCR-ABL1 expression, showed an altered miRNome. We confirmed by RT-qPCR that the levels of miR-196a-5p were increased more than nine-fold in CD26+ ( BCR-ABL1+ ) vs. CD26- ( BCR-ABL1- ) CD34+ CD38- fractions from CML-CP patients at diagnosis, and in silico analysis revealed a significant association to lipid metabolism and hematopoiesis functions. In the light of recent descriptions of increased oxidative metabolism in CML LSC-enriched fractions, these results serve as a guide for future functional studies that evaluate the role of microRNAs in this process. Metabolic vulnerabilities in LSCs open the road for new therapeutic strategies. This is the first report of the miRNome of CML-CP CD34+ CD38- fractions that distinguishes between CD26+ ( BCR-ABL1+ ) and their CD26- ( BCR-ABL1- ) counterparts, providing valuable data for future studies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Ruiz, Sánchez, Bonecker, Furtado, Koile, Yankilevich, Cranco, Custidiano, Freitas, Moiraghi, Pérez, Pavlovsky, Varela, Ventriglia, Sánchez Ávalos, Larripa, Zalcberg, Mordoh, Valent and Bianchini.)- Published
- 2021
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18. Fluorescence cross-correlation spectroscopy as a valuable tool to characterize cationic liposome-DNA nanoparticle assembly.
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Gómez-Varela AI, Gaspar R, Miranda A, Assis JL, Valverde RHF, Einicker-Lamas M, Silva BFB, and De Beule PAA
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- DNA genetics, Spectrometry, Fluorescence, Transfection, Liposomes, Nanoparticles
- Abstract
The development of nonviral gene delivery vehicles for therapeutic applications requires methods capable of quantifying the association between the genes and their carrier counterparts. Here we investigate the potential of fluorescence cross-correlation spectroscopy (FCCS) to characterize and optimize the assembly of nonviral cationic liposome (CL)-DNA complexes based on a CL formulation consisting of the cationic lipid DOTAP and zwitterionic lipid DOPC. We use a DNA plasmid for lipoplex loading encoding the Oct4 gene, critically involved in reprogramming somatic cells into induced pluripotent stem cells. We demonstrate that FCCS is able to quantitatively determine the extent of the association between DNA and the liposomes and assess its loading capacity. We also establish that the cationic lipid fraction, being proportional to the liposome membrane charge density, as well as charge ratio between the CLs and anionic DNA play an important role in the degree of interaction between the liposomes and DNA., (© 2020 Wiley-VCH GmbH.)
- Published
- 2021
- Full Text
- View/download PDF
19. Effect of predation risk and ectoparasitic louse flies on physiological stress condition of the red-tailed tropicbird ( Phaethon rubricauda ) from Rapa Nui and Salas & Gómez islands.
- Author
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Luna N, Varela AI, Luna-Jorquera G, and Brokordt K
- Abstract
Background: Introduced predators at seabird colonies and parasites may have lethal and/or sub-lethal consequences for bird populations. We assessed the potential sub-lethal negative effects of these stressors in a native seabird listed as vulnerable in its south-eastern pacific distribution. This study was conducted in two red-tailed tropicbird ( Phaethon rubricauda ) colonies, one located in Rapa Nui Island, which is threatened by the presence of introduced predators, and the other located in Salas & Gómez Island, which has no introduced predators, but birds are infested by ectoparasitic louse flies., Methods: The effects on physiological stress traits of both, predation risk on different nest types (protected and exposed) on Rapa Nui, and different levels of louse flies' parasitic loads on Salas & Gómez were studied. Three variables were analyzed: the heterophil/lymphocyte (H/L) ratio, the transcriptional levels of mRNA HSP70 in blood, and the body condition. These stress indicators and leukocyte counts were compared between colonies., Results: No significant differences were found in any stress indicator between different nest types within Rapa Nui, showing that the effect of predator's presence was the same for adults nesting in both, protected and exposed nests. No significant correlation was found between louse flies' parasitic loads and any stress indicators in the birds of Salas & Gómez. Also, there was no difference in any stress indicator between islands. However, a significant opposite trend between islands was found in the eosinophil, lymphocyte, and monocyte counts when related to body condition., Conclusions: We found a lack of significant differentiation in all the stress level indicators assessed within and between islands. The presence of louse flies in Salas & Gómez vs. the absence of this parasite at Rapa Nui may be the cause for the significant difference in the trend of eosinophil, lymphocyte and monocyte counts between the islands. However, further studies are necessary to elucidate the reason for this difference and to better investigate the lethal effects of introduced predators on the Rapa Nui colony to evaluate appropriate conservation measures for this native seabird., Competing Interests: The authors declare that they have no competing interests., (© 2020 Luna et al.)
- Published
- 2020
- Full Text
- View/download PDF
20. Simultaneous co-localized super-resolution fluorescence microscopy and atomic force microscopy: combined SIM and AFM platform for the life sciences.
- Author
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Gómez-Varela AI, Stamov DR, Miranda A, Alves R, Barata-Antunes C, Dambournet D, Drubin DG, Paiva S, and De Beule PAA
- Abstract
Correlating data from different microscopy techniques holds the potential to discover new facets of signaling events in cellular biology. Here we report for the first time a hardware set-up capable of achieving simultaneous co-localized imaging of spatially correlated far-field super-resolution fluorescence microscopy and atomic force microscopy, a feat only obtained until now by fluorescence microscopy set-ups with spatial resolution restricted by the Abbe diffraction limit. We detail system integration and demonstrate system performance using sub-resolution fluorescent beads and applied to a test sample consisting of human bone osteosarcoma epithelial cells, with plasma membrane transporter 1 (MCT1) tagged with an enhanced green fluorescent protein (EGFP) at the N-terminal.
- Published
- 2020
- Full Text
- View/download PDF
21. Genetic and morphological divergence at a biogeographic break in the beach-dwelling brooder Excirolana hirsuticauda Menzies (Crustacea, Peracarida).
- Author
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Haye PA, Segovia NI, Varela AI, Rojas R, Rivadeneira MM, and Thiel M
- Subjects
- Analysis of Variance, Animals, Bayes Theorem, Body Size, DNA, Mitochondrial genetics, Electron Transport Complex IV genetics, Gene Flow, Genetic Loci, Genetic Variation, Haplotypes genetics, Isopoda classification, Microsatellite Repeats genetics, Phylogeny, Principal Component Analysis, Isopoda anatomy & histology, Isopoda genetics, Phylogeography
- Abstract
Background: There is a biogeographic break located at 30°S in the southeast Pacific, in a coastal area of strong environmental discontinuities. Several marine benthic taxa with restricted dispersal have a coincident phylogeographic break at 30°S, indicating that genetic structure is moulded by life history traits that limit gene flow and thereby promote divergence and speciation. In order to evaluate intraspecific divergence at this biogeographic break, we investigated the genetic and morphological variation of the directly developing beach isopod Excirolana hirsuticauda along 1900 km of the southeast Pacific coast, across 30°S., Results: The COI sequences and microsatellite data both identified a strong discontinuity between populations of E. hirsuticauda to the north and south of 30°S, and a second weaker phylogeographic break at approximately 35°S. The three genetic groups were evidenced by different past demographic and genetic diversity signatures, and were also clearly distinguished with microsatellite data clustering. The COI sequences established that the genetic divergence of E. hirsuticauda at 30°S started earlier than divergence at 35°. Additionally, the three groups have different past demographic signatures, with probable demographic expansion occurring earlier in the southern group (south of 35°S), associated with Pleistocene interglacial periods. Interestingly, body length, multivariate morphometric analyses, and the morphology of a fertilization-related morphological character in males, the appendix masculina, reinforced the three genetic groups detected with genetic data., Conclusions: The degree of divergence of COI sequences, microsatellite data, and morphology was concordant and showed two geographic areas in which divergence was promoted at differing historical periods. Variation in the appendix masculina of males has probably promoted reproductive isolation. This variation together with gene flow restrictions promoted by life history traits, small body size, oceanographic discontinuities and sandy-beach habitat continuity, likely influenced species divergence at 30°S in the southeast Pacific coast. The degree of genetic and morphological differentiation of populations to the north and south of 30°S suggests that E. hirsuticauda harbours intraspecific divergence consistent with reproductive isolation and an advanced stage of speciation. The speciation process within E. hirsuticauda has been shaped by both restrictions to gene flow and a prezygotic reproductive barrier.
- Published
- 2019
- Full Text
- View/download PDF
22. PET-adapted therapy after three cycles of ABVD for all stages of Hodgkin lymphoma: results of the GATLA LH-05 trial.
- Author
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Pavlovsky A, Fernandez I, Kurgansky N, Prates V, Zoppegno L, Negri P, Milone G, Cerutti I, Zabaljauregui S, Mariano R, Grecco HF, Basquiera AL, Saba S, Rudoy S, Sackmann F, Castano V, Remaggi G, Cabrejo M, Roveri E, Casale MF, Cabane V, Taus R, Venturini C, Sakamoto F, Varela AI, Riddick M, and Pavlovsky S
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Antineoplastic Combined Chemotherapy Protocols pharmacology, Bleomycin pharmacology, Bleomycin therapeutic use, Dacarbazine pharmacology, Dacarbazine therapeutic use, Doxorubicin pharmacology, Doxorubicin therapeutic use, Female, Hodgkin Disease pathology, Humans, Male, Middle Aged, Prospective Studies, Survival Analysis, Vinblastine pharmacology, Vinblastine therapeutic use, Young Adult, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Hodgkin Disease diagnostic imaging, Hodgkin Disease drug therapy, Positron-Emission Tomography methods
- Abstract
The role of Ann Arbor staging in determining treatment intensity after achieving a negative positron emission tomography (PET) has not been established in classical Hodgkin lymphoma (cHL). Patients with stage I-IV cHL, received three cycles of ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine) and an interim PET scan (PET3). PET3-negative patients received no further therapy. PET3-positive patients received three additional cycles of ABVD plus involved-field radiation therapy or salvage chemotherapy, if refractory to ABVD, and were re-evaluated by PET scan (PET6). Study endpoints were 3-year progression-free survival (PFS) and overall survival (OS) rates. Two hundred and thirty-nine patients with early-stage and 138 with advanced-stage were evaluable. Overall, 260 patients (70%) were PET3-negative and had higher 3-year PFS (90% vs. 65%; P < 0·0001) and OS (98% vs. 92%; P = 0·007) rates than PET3-positive patients. All PET3-negative patients, regardless of disease stage at diagnosis, achieved similarly good PFS (90-91%; P = 0·76) and OS (97-99%). The only independent prognostic factor for PFS was PET3-negativity (Hazard ratio 3·8; 95% confidence interval 2·4-6·3; P < 0·0001). This study suggests that cHL patients who achieve a negative PET3 following ABVD have an excellent outcome, regardless of stage at diagnosis. An appropriately powered, phase III trial will be necessary to confirm these findings., (© 2019 British Society for Haematology and John Wiley & Sons Ltd.)
- Published
- 2019
- Full Text
- View/download PDF
23. Study of Different Sol-Gel Coatings to Enhance the Lifetime of PDMS Devices: Evaluation of Their Biocompatibility.
- Author
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Aymerich M, Gómez-Varela AI, Álvarez E, and Flores-Arias MT
- Abstract
A study of PDMS (polydimethylsiloxane) sol-gel-coated channels fabricated using soft lithography and a laser direct writing technique is presented. PDMS is a biocompatible material that presents a high versatility to reproduce several structures. It is widely employed in the fabrication of preclinical devices due to its advantages but it presents a rapid chemical deterioration to organic solvents. The use of sol-gel layers to cover the PDMS overcomes this problem since it provides the robustness of glass for the structures made with PDMS, decreasing its deterioration and changing the biocompatibility of the surface. In this work, PDMS channels are coated with three different kinds of sol-gel compositions (60MTES/40TEOS, 70MTES/30TISP and 80MTES/20TISP). The endothelial cell adhesion to the different coated devices is evaluated in order to determine the most suitable sol-gel preparation conditions to enhance cellular adhesion.
- Published
- 2016
- Full Text
- View/download PDF
24. [Interview with Mrs. Blanca Marti de David Almeida].
- Author
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Velandia de Varela AI and Morgan de Morillo G
- Subjects
- Colombia, History of Medicine, Nursing
- Published
- 1974
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