26 results on '"Navarro, R"'
Search Results
2. Caenorhabditis elegans ATPase inhibitor factor 1 (IF1) MAI-2 preserves the mitochondrial membrane potential (Δψm) and is important to induce germ cell apoptosis
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Fernández-Cárdenas, L. P., primary, Villanueva-Chimal, E., additional, Salinas, L. S., additional, José-Nuñez, C., additional, Tuena de Gómez Puyou, M., additional, and Navarro, R. E., additional
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- 2017
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3. Caenorhabditis elegans ATPase inhibitor factor 1 (IF1) MAI-2 preserves the mitochondrial membrane potential (Δψm) and is important to induce germ cell apoptosis.
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Fernández-Cárdenas, L. P., Villanueva-Chimal, E., Salinas, L. S., José-Nuñez, C., Tuena de Gómez Puyou, M., and Navarro, R. E.
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CAENORHABDITIS elegans ,CAENORHABDITIS ,ADENOSINE triphosphatase ,GERM cells ,APOPTOSIS - Abstract
When the electrochemical proton gradient is disrupted in the mitochondria, IF
1 (Inhibitor Factor-1) inhibits the reverse hydrolytic activity of the F1 Fo -ATP synthase, thereby allowing cells to conserve ATP at the expense of losing the mitochondrial membrane potential (Δψm ). The function of IF1 has been studied mainly in different cell lines, but these studies have generated contrasting results, which have not been helpful to understand the real role of this protein in a whole organism. In this work, we studied IF1 function in Caenorhabditis elegans to understand IF1 ´s role in vivo. C. elegans has two inhibitor proteins of the F1 Fo -ATPase, MAI-1 and MAI-2. To determine their protein localization in C. elegans, we generated translational reporters and found that MAI-2 is expressed ubiquitously in the mitochondria; conversely, MAI-1 was found in the cytoplasm and nuclei of certain tissues. By CRISPR/Cas9 genome editing, we generated mai-2 mutant alleles. Here, we showed that mai-2 mutant animals have normal progeny, embryonic development and lifespan. Contrasting with the results previously obtained in cell lines, we found no evident defects in the mitochondrial network, dimer/monomer ATP synthase ratio, ATP concentration or respiration. Our results suggest that some of the roles previously attributed to IF1 in cell lines could not reflect the function of this protein in a whole organism and could be attributed to specific cell lines or methods used to silence, knockout or overexpress this protein. However, we did observe that animals lacking IF1 had an enhanced Δψm and lower physiological germ cell apoptosis. Importantly, we found that mai-2 mutant animals must be under stress to observe the role of IF1 . Accordingly, we observed that mai-2 mutant animals were more sensitive to heat shock, oxidative stress and electron transport chain blockade. Furthermore, we observed that IF1 is important to induce germ cell apoptosis under certain types of stress. Here, we propose that MAI-2 might play a role in apoptosis by regulating Δψm . Additionally, we suggest that IF1 function is mainly observed under stress and that, under physiological conditions, this protein does not play an essential role. [ABSTRACT FROM AUTHOR]- Published
- 2017
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4. Patterns of cognitive-emotional change after cognitive-behavioural treatment in emotional disorders: A 12-month longitudinal cluster analysis.
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Barrio-Martínez S, Rodriguez-Perez N, Priede A, Medrano LA, Muñoz-Navarro R, Moriana JA, Carpallo-González M, Prieto-Vila M, Ruiz-Rodríguez P, Cano-Vindel A, and González-Blanch C
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- Humans, Male, Female, Cluster Analysis, Adult, Longitudinal Studies, Middle Aged, Anxiety therapy, Anxiety psychology, Depression therapy, Depression psychology, Treatment Outcome, Cognitive Behavioral Therapy methods, Quality of Life, Emotions, Cognition physiology
- Abstract
Introduction: The aim of this study was to use cluster analysis based on the trajectory of five cognitive-emotional processes (worry, rumination, metacognition, cognitive reappraisal and expressive suppression) over time to explore differences in clinical and performance variables in primary care patients with emotional symptoms., Methods: We compared the effect of adding transdiagnostic cognitive-behavioural therapy (TD-CBT) to treatment as usual (TAU) according to cluster membership and sought to determine the variables that predicted cluster membership. 732 participants completed scales about cognitive-emotional processes, anxiety and depressive symptoms, functioning, and quality of life (QoL) at baseline, posttreatment, and at 12 months. Longitudinal cluster analysis and logistic regression analyses were carried out., Results: A two-cluster solution was chosen as the best fit, named as "less" or "more" improvement in cognitive-emotional processes. Individuals who achieved more improvement in cognitive-emotional processes showed lower emotional symptoms and better QoL and functioning at all three time points. TAU+TD-CBT, income level, QoL and anxiety symptoms were significant predictors of cluster membership., Conclusions: These results underscore the value of adding TD-CBT to reduce maladaptive cognitive-emotional regulation strategies. These findings highlight the importance of the processes of change in therapy and demonstrate the relevance of the patient's cognitive-emotional profile in improving treatment outcomes., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Barrio-Martínez et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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5. Comparing psychological versus pharmacological treatment in emotional disorders: A network analysis.
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Jurado-González F, García-Torres F, Contreras A, Muñoz-Navarro R, González-Blanch C, Adrián Medrano L, Ruiz-Rodríguez P, Moreno EM, Pérez-Dueñas C, Cano-Vindel A, and Moriana JA
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- Humans, Anxiety therapy, Anxiety Disorders therapy, Depression therapy, Mood Disorders, Treatment Outcome, Multicenter Studies as Topic, Randomized Controlled Trials as Topic, Cognitive Behavioral Therapy methods
- Abstract
Transdiagnostic group cognitive behavioural therapy (TD-GCBT) is more effective in improving symptoms and severity of emotional disorders (EDs) than treatment as usual (TAU; usually pharmacological treatment). However, there is little research that has examined the effects of these treatments on specific symptoms. This study used Network Intervention Analysis (NIA) to investigate the direct and differential effects of TD-GCBT + TAU and TAU on specific symptoms of anxiety and depression. Data are from a multicentre randomised clinical trial (N = 1061) comparing TD-GCBT + TAU versus TAU alone for EDs. The networks included items from the PHQ-9 (depression) and GAD-7 (anxiety) questionnaire and mixed graphical models were estimated at pre-treatment, post-treatment and 3-, 6- and 12-month follow-up. Results revealed that TD-GCBT + TAU was associated with direct effects, mainly on several anxiety symptoms and depressed mood after treatment. New direct effects on other depressive symptoms emerged during the follow-up period promoted by TD-GCBT compared to TAU. Our results suggest that the improvement of anxiety symptoms after treatment might precipitate a wave of changes that favour a decrease in depressive symptomatology. NIA is a methodology that can provide fine-grained insight into the likely pathways through which treatments exert their effects., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Jurado-González et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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6. Cost-effectiveness of transdiagnostic group cognitive behavioural therapy versus group relaxation therapy for emotional disorders in primary care (PsicAP-Costs2): Protocol for a multicentre randomised controlled trial.
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González-Blanch C, Barrio-Martínez S, Priede A, Martínez-Gómez S, Pérez-García-Abad S, Miras-Aguilar M, Ruiz-Gutiérrez J, Muñoz-Navarro R, Ruiz-Rodríguez P, Medrano LA, Prieto-Vila M, Carpallo-González M, Aguilera-Martín Á, Gálvez-Lara M, Cuadrado F, Moreno E, García-Torres F, Venceslá JF, Corpas J, Jurado-González FJ, Moriana JA, and Cano-Vindel A
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- Cost-Benefit Analysis, Treatment Outcome, Primary Health Care, Quality of Life, Randomized Controlled Trials as Topic, Multicenter Studies as Topic, Relaxation Therapy, Cognitive Behavioral Therapy methods
- Abstract
Several randomised controlled trials (RCT) have demonstrated the superiority of transdiagnostic group cognitive-behavioural therapy (TD-CBT) to treatment as usual (TAU) for emotional disorders in primary care. To date, however, no RCTs have been conducted to compare TD-CBT to another active intervention in this setting. Our aim is to conduct a single-blind RCT to compare group TD-CBT plus TAU to progressive muscle relaxation (PMR) plus TAU in adults (age 18 to 65 years) with a suspected emotional disorder. We expect that TD-CBT + TAU will be more cost-effective than TAU + PMR, and that these gains will be maintained at the 12-month follow-up. Seven therapy sessions (1.5 hours each) will be offered over a 24-week period. The study will be carried out at four primary care centres in Cantabria, Spain. The study will take a societal perspective. Psychological assessments will be made at three time points: baseline, post-treatment, and at 12-months. The following variables will be evaluated: clinical symptoms (anxiety, depression, and/or somatic); functioning; quality of life (QoL); cognitive-emotional factors (rumination, worry, attentional and interpretative biases, emotion regulation and meta-cognitive beliefs); and satisfaction with treatment. Data on health service use, medications, and sick days will be obtained from electronic medical records. Primary outcome measures will include: incremental cost-effectiveness ratios (ICER) and incremental cost-utility ratios (ICURs). Secondary outcome measures will include: clinical symptoms, QoL, functioning, and treatment satisfaction. Bootstrap sampling will be used to assess uncertainty of the results. Secondary moderation and mediation analyses will be conducted. Two questionnaires will be administered at sessions 1, 4, and 7 to assess therapeutic alliance and group satisfaction. If this trial is successful, widespread application of this cost-effective treatment could greatly improve access to psychological treatment for emotional disorders in the context of increasing demand for mental healthcare in primary care. Trial registration: ClinicalTrials.gov: Cost-effectiveness of a Transdiagnostic Psychological Treatment for Emotional Disorders in Primary Care (PsicAP). NCT05314920., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 González-Blanch et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
- Published
- 2023
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7. HIV and antiretroviral treatment knowledge gaps and psychosocial burden among persons living with HIV in Lima, Peru.
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Navarro R, Paredes JL, Echevarria J, González-Lagos E, Graña A, Mejía F, and Otero L
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- Adolescent, Adult, Anti-Retroviral Agents therapeutic use, Depression drug therapy, Depression etiology, Depression psychology, Disclosure, Female, HIV Infections complications, HIV Infections drug therapy, HIV Infections psychology, Humans, Male, Middle Aged, Peru epidemiology, Young Adult, Depression epidemiology, HIV Infections epidemiology, Viral Load
- Abstract
This study aims to describe knowledge on HIV and antiretroviral (ARV) treatment and psychosocial factors among people living with HIV (PLWH) in Lima, Perú, to explore characteristics associated to this knowledge, and determine its impact on sustained viral suppression. A cross-sectional survey was conducted among 171 PLWH at the largest referral health care center in Lima. The psychosocial factors measured were depression, risk of alcoholism, use of illegal drugs and disclosure. A participant had "poor knowledge" when less than 80% of replies were correct. Sustained viral suppression was defined as two consecutive viral loads under 50 copies/mL. A total of 49% and 43% had poor HIV and ARV knowledge respectively; 48% of the study population screened positive for depression and 27% reported feeling unsupported by the person they disclosed to. The largest gaps in HIV and ARV knowledge were among 98 (57%) that did not recognize that HIV increased the risk of cancer and among 57 (33%) participants that did not disagree with the statement that taking a double dose of ARV if they missed one. Moderate depression was significantly associated to poor HIV and ARV knowledge. Non-disclosure and being on ARVs for less than 6 months were associated with not achieving sustained viral suppression. Our findings highlight important HIV and ARV knowledge gaps of PLWH and a high burden of psychosocial problems, especially of depression, among PLWH in Lima, Peru. Increasing knowledge and addressing depression and disclosure could improve care of PLWH., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2021
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8. Correction: Reliability of technologies to measure the barbell velocity: Implications for monitoring resistance training.
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Martínez-Cava A, Hernández-Belmonte A, Courel-Ibáñez J, Morán-Navarro R, González-Badillo JJ, and Pallarés JG
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[This corrects the article DOI: 10.1371/journal.pone.0232465.].
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- 2020
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9. Reliability of technologies to measure the barbell velocity: Implications for monitoring resistance training.
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Martínez-Cava A, Hernández-Belmonte A, Courel-Ibáñez J, Morán-Navarro R, González-Badillo JJ, and Pallarés JG
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- Adult, Humans, Male, Monitoring, Physiologic instrumentation, Smartphone, Young Adult, Monitoring, Physiologic methods, Resistance Training, Weight Lifting
- Abstract
This study investigated the inter- and intra-device agreement of four new devices marketed for barbell velocity measurement. Mean, mean propulsive and peak velocity outcomes were obtained for bench press and full squat exercises along the whole load-velocity spectrum (from light to heavy loads). Measurements were simultaneously registered by two linear velocity transducers T-Force, two linear position transducers Speed4Lifts, two smartphone video-based systems My Lift, and one 3D motion analysis system STT. Calculations included infraclass correlation coefficient (ICC), Bland-Altman Limits of Agreement (LoA), standard error of measurement (SEM), smallest detectable change (SDC) and maximum errors (MaxError). Results were reported in absolute (m/s) and relative terms (%1RM). Three velocity segments were differentiated according to the velocity-load relationships for each exercise: heavy (≥ 80% 1RM), medium (50% < 1RM < 80%) and light loads (≤ 50% 1RM). Criteria for acceptable reliability were ICC > 0.990 and SDC < 0.07 m/s (~5% 1RM). The T-Force device shown the best intra-device agreement (SDC = 0.01-0.02 m/s, LoA <0.01m/s, MaxError = 1.3-2.2%1RM). The Speed4Lifts and STT were found as highly reliable, especially against lifting velocities ≤1.0 m/s (Speed4Lifts, SDC = 0.01-0.05 m/s; STT, SDC = 0.02-0.04 m/s), whereas the My Lift app showed the worst results with errors well above the acceptable levels (SDC = 0.26-0.34 m/s, MaxError = 18.9-24.8%1RM). T-Force stands as the preferable option to assess barbell velocity and to identify technical errors of measurement for emerging monitoring technologies. Both the Speed4Lifts and STT are fine alternatives to T-Force for measuring velocity against high-medium loads (velocities ≤ 1.0 m/s), while the excessive errors of the newly updated My Lift app advise against the use of this tool for velocity-based resistance training., Competing Interests: The authors have declared that no competing interests exist.
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- 2020
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10. Influence of Nd:YAG laser on the penetration of a bioceramic root canal sealer into dentinal tubules: A confocal analysis.
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Jardim Del Monaco R, Tavares de Oliveira M, de Lima AF, Scarparo Navarro R, Zanetti RV, de Fátima Teixeira da Silva D, and Horliana ACRT
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- Bicuspid pathology, Bicuspid radiation effects, Dental Pulp Cavity pathology, Humans, In Vitro Techniques, Materials Testing, Microscopy, Confocal, Root Canal Therapy, Dental Pulp Cavity radiation effects, Lasers, Solid-State, Root Canal Filling Materials radiation effects, Zinc Oxide-Eugenol Cement radiation effects
- Abstract
Objective: The aim of this in vitro study, is to evaluate the penetration of a bioceramic root canal sealer into dentinal tubules at 3 mm and 5 mm from the apex after Nd:YAG laser irradiation., Methods: Forty freshly extracted human mandibular premolars were prepared using Reciproc® and irrigated with 17% ethylenediaminetetraacetic acid (EDTA). Teeth were divided into 4 groups: group 1, obturated with control sealer (AH Plus®); group 2, obturated with bioceramic sealer (Endosequence BC Sealer®); group 3, Nd:YAG laser + control sealer (AH Plus®); and group 4, Nd:YAG laser + bioceramic sealer (Endosequence BC Sealer®). The samples were transversely sectioned 3 mm and 5 mm from the apex and examined using confocal laser scanning microscopy. Two parameters were measured: 1) sealer penetration into dentinal tubules of the root canal and 2) sealer penetration into the perimeter of the root canal walls., Results: Penetration analysis showed that bioceramic sealer had a higher penetration at depths of 3 and 5 mm than that of the control sealer, regardless of laser use (p <0.05). Perimeter analysis showed that there was no difference between both sealers at a depth of 3 mm (p <0.05), regardless of laser use. At a depth of 5 mm, bioceramic sealer and laser showed a greater perimeter of penetration (p <0.05) than the control sealer., Conclusion: The use of Nd:YAG laser did not compromise the penetration of bioceramic sealer into dentinal tubules of root canals at 3 mm and 5 mm from the apex., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2018
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11. Factor structure and measurement invariance across various demographic groups and over time for the PHQ-9 in primary care patients in Spain.
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González-Blanch C, Medrano LA, Muñoz-Navarro R, Ruíz-Rodríguez P, Moriana JA, Limonero JT, Schmitz F, and Cano-Vindel A
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- Adolescent, Adult, Factor Analysis, Statistical, Female, Humans, Male, Middle Aged, Socioeconomic Factors, Spain, Time Factors, Young Adult, Depression diagnosis, Patient Health Questionnaire, Primary Health Care
- Abstract
The Patient Health Questionnaire (PHQ-9) is a widely-used screening tool for depression in primary care settings. The purpose of the present study is to identify the factor structure of the PHQ-9 and to examine the measurement invariance of this instrument across different sociodemographic groups and over time in a sample of primary care patients in Spain. Data came from 836 primary care patients enrolled in a randomized controlled trial (PsicAP study) and a subsample of 218 patients who participated in a follow-up assessment at 3 months. Confirmatory factor analysis (CFA) was used to test one- and two-factor structures identified in previous studies. Analyses of multiple-group invariance were conducted to determine the extent to which the factor structure is comparable across various demographic groups (i.e., gender, age, marital status, level of education, and employment situation) and over time. Both one-factor and two-factor re-specified models met all the pre-established fit criteria. However, because the factors identified in the two-factor model were highly correlated (r = .86), the one-factor model was preferred for its parsimony. Multi-group CFA indicated measurement invariance across different demographic groups and across time. The present findings suggest that physicians in Spain can use the PHQ-9 to obtain a global score for depression severity in different demographic groups and to reliably monitor changes over time in the primary care setting.
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- 2018
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12. biochem4j: Integrated and extensible biochemical knowledge through graph databases.
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Swainston N, Batista-Navarro R, Carbonell P, Dobson PD, Dunstan M, Jervis AJ, Vinaixa M, Williams AR, Ananiadou S, Faulon JL, Mendes P, Kell DB, Scrutton NS, and Breitling R
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- Computational Biology, Internet, Databases, Factual, User-Computer Interface
- Abstract
Biologists and biochemists have at their disposal a number of excellent, publicly available data resources such as UniProt, KEGG, and NCBI Taxonomy, which catalogue biological entities. Despite the usefulness of these resources, they remain fundamentally unconnected. While links may appear between entries across these databases, users are typically only able to follow such links by manual browsing or through specialised workflows. Although many of the resources provide web-service interfaces for computational access, performing federated queries across databases remains a non-trivial but essential activity in interdisciplinary systems and synthetic biology programmes. What is needed are integrated repositories to catalogue both biological entities and-crucially-the relationships between them. Such a resource should be extensible, such that newly discovered relationships-for example, those between novel, synthetic enzymes and non-natural products-can be added over time. With the introduction of graph databases, the barrier to the rapid generation, extension and querying of such a resource has been lowered considerably. With a particular focus on metabolic engineering as an illustrative application domain, biochem4j, freely available at http://biochem4j.org, is introduced to provide an integrated, queryable database that warehouses chemical, reaction, enzyme and taxonomic data from a range of reliable resources. The biochem4j framework establishes a starting point for the flexible integration and exploitation of an ever-wider range of biological data sources, from public databases to laboratory-specific experimental datasets, for the benefit of systems biologists, biosystems engineers and the wider community of molecular biologists and biological chemists.
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- 2017
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13. Constructing a biodiversity terminological inventory.
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Nguyen NTH, Soto AJ, Kontonatsios G, Batista-Navarro R, and Ananiadou S
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- Algorithms, Libraries, Search Engine, Semantics, Terminology as Topic, Biodiversity, Data Mining methods
- Abstract
The increasing growth of literature in biodiversity presents challenges to users who need to discover pertinent information in an efficient and timely manner. In response, text mining techniques offer solutions by facilitating the automated discovery of knowledge from large textual data. An important step in text mining is the recognition of concepts via their linguistic realisation, i.e., terms. However, a given concept may be referred to in text using various synonyms or term variants, making search systems likely to overlook documents mentioning less known variants, which are albeit relevant to a query term. Domain-specific terminological resources, which include term variants, synonyms and related terms, are thus important in supporting semantic search over large textual archives. This article describes the use of text mining methods for the automatic construction of a large-scale biodiversity term inventory. The inventory consists of names of species, amongst which naming variations are prevalent. We apply a number of distributional semantic techniques on all of the titles in the Biodiversity Heritage Library, to compute semantic similarity between species names and support the automated construction of the resource. With the construction of our biodiversity term inventory, we demonstrate that distributional semantic models are able to identify semantically similar names that are not yet recorded in existing taxonomies. Such methods can thus be used to update existing taxonomies semi-automatically by deriving semantically related taxonomic names from a text corpus and allowing expert curators to validate them. We also evaluate our inventory as a means to improve search by facilitating automatic query expansion. Specifically, we developed a visual search interface that suggests semantically related species names, which are available in our inventory but not always in other repositories, to incorporate into the search query. An assessment of the interface by domain experts reveals that our query expansion based on related names is useful for increasing the number of relevant documents retrieved. Its exploitation can benefit both users and developers of search engines and text mining applications.
- Published
- 2017
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14. A detailed heterogeneous agent model for a single asset financial market with trading via an order book.
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Mota Navarro R and Larralde H
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- Commerce, Computer Simulation, Financial Statements, Models, Economic, Oscillometry, Financial Management economics, Investments economics, Models, Statistical
- Abstract
We present an agent based model of a single asset financial market that is capable of replicating most of the non-trivial statistical properties observed in real financial markets, generically referred to as stylized facts. In our model agents employ strategies inspired on those used in real markets, and a realistic trade mechanism based on a double auction order book. We study the role of the distinct types of trader on the return statistics: specifically, correlation properties (or lack thereof), volatility clustering, heavy tails, and the degree to which the distribution can be described by a log-normal. Further, by introducing the practice of "profit taking", our model is also capable of replicating the stylized fact related to an asymmetry in the distribution of losses and gains.
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- 2017
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15. Docosahexaenoic Acid Supplemented Diet Influences the Orchidectomy-Induced Vascular Dysfunction in Rat Mesenteric Arteries.
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Villalpando DM, Navarro R, Del Campo L, Largo C, Muñoz D, Tabernero M, Baeza R, Otero C, García HS, and Ferrer M
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- Acetylcholine pharmacology, Animals, Blood Pressure, Docosahexaenoic Acids pharmacology, Male, Nitric Oxide biosynthesis, Prostaglandins metabolism, Rats, Superoxides metabolism, Vasodilator Agents pharmacology, Dietary Supplements, Mesenteric Arteries drug effects, Mesenteric Arteries physiopathology, Orchiectomy
- Abstract
Over the past few decades, the cardiovascular benefits of a high dietary intake of long-chain polyunsaturated fatty acids (PUFAs), like docosahexaenoic acid (DHA), have been extensively studied. However, many of the molecular mechanisms and effects exerted by PUFAs have yet to be well explained. The lack of sex hormones alters vascular tone, and we have described that a DHA-supplemented diet to orchidectomized rats improve vascular function of the aorta. Based on these data and since the mesenteric artery importantly controls the systemic vascular resistance, the objective of this study was to analyze the effect of a DHA-supplemented diet on the mesenteric vascular function from orchidectomized rats. For this purpose mesenteric artery segments obtained from control, orchidectomized or orchidectomized plus DHA-supplemented diet were utilized to analyze: (1) the release of prostanoids, (2) formation of NO and ROS, (3) the vasodilator response to acetylcholine (ACh), as well as the involvement of prostanoids and NO in this response, and (4) the vasoconstrictor response to electrical field stimulation (EFS), analyzing also the effect of exogenous noradrenaline (NA), and the NO donor, sodium nitroprusside (SNP). The results demonstrate beneficial effects of DHA on the vascular function in orchidectomized rats, which include a decrease in the prostanoids release and superoxide formation that were previously augmented by orchidectomy. Additionally, there was an increase in endothelial NO formation and the response to ACh, in which NO involvement and the participation of vasodilator prostanoids were increased. DHA also reversed the decrease in EFS-induced response caused by orchidectomy. All of these findings suggest beneficial effects of DHA on vascular function by reversing the neurogenic response and the endothelial dysfunction caused by orchidectomy., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2017
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16. High-Throughput Sequencing Reveals Circulating miRNAs as Potential Biomarkers of Kidney Damage in Patients with Systemic Lupus Erythematosus.
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Navarro-Quiroz E, Pacheco-Lugo L, Lorenzi H, Díaz-Olmos Y, Almendrales L, Rico E, Navarro R, España-Puccini P, Iglesias A, Egea E, and Aroca G
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- Adult, Female, Gene Expression Profiling methods, Humans, Male, MicroRNAs genetics, Middle Aged, Principal Component Analysis, Reverse Transcriptase Polymerase Chain Reaction, Young Adult, Biomarkers blood, High-Throughput Nucleotide Sequencing methods, Lupus Erythematosus, Systemic genetics, Lupus Nephritis genetics, MicroRNAs blood
- Abstract
Renal involvement is one of the most severe manifestations of systemic lupus erythematosus (SLE). Renal biopsy is the gold standard when it comes to knowing whether a patient has lupus nephritis, and the degree of renal disease present. However, the biopsy has various complications, bleeding being the most common. Therefore, the development of alternative, non-invasive diagnostic tests for kidney disease in patients with SLE is a priority. Micro RNAs (miRNAs) are differentially expressed in various tissues, and changes in their expression have been associated with several pathological processes. The aim of this study was to identify changes in the abundance of miRNAs in plasma samples from patients with lupus nephritis that could potentially allow the diagnosis of renal damage in SLE patients. This is an observational case-control cross-sectional study, in which we characterized the differential abundance profiles of miRNAs among patients with different degrees of lupus compared with SLE patients without renal involvement and healthy control individuals. We found 89 miRNAs with changes in their abundance between lupus nephritis patients and healthy controls, and 17 miRNAs that showed significant variations between SLE patients with or without renal involvement. Validation for qPCR of a group of miRNAs on additional samples from lupus patients with or without nephritis, and from healthy individuals, showed that five miRNAs presented an average detection sensitivity of 97%, a specificity of 70.3%, a positive predictive value of 82.5%, a negative predictive value of 96% and a diagnosis efficiency of 87.9%. These results strongly suggest that miR-221-5p, miR-380-3p, miR-556-5p, miR-758-3p and miR-3074-3p are potential diagnostic biomarkers of lupus nephritis in patients with SLE. The observed differential pattern of miRNA abundance may have functional implications in the pathophysiology of SLE renal damage., Competing Interests: The authors have declared that no competing interests exist.
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- 2016
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17. Validity and Reliability of Ventilatory and Blood Lactate Thresholds in Well-Trained Cyclists.
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Pallarés JG, Morán-Navarro R, Ortega JF, Fernández-Elías VE, and Mora-Rodriguez R
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Purpose: The purpose of this study was to determine, i) the reliability of blood lactate and ventilatory-based thresholds, ii) the lactate threshold that corresponds with each ventilatory threshold (VT1 and VT2) and with maximal lactate steady state test (MLSS) as a proxy of cycling performance., Methods: Fourteen aerobically-trained male cyclists ([Formula: see text] 62.1±4.6 ml·kg-1·min-1) performed two graded exercise tests (50 W warm-up followed by 25 W·min-1) to exhaustion. Blood lactate, [Formula: see text] and [Formula: see text] data were collected at every stage. Workloads at VT1 (rise in [Formula: see text];) and VT2 (rise in [Formula: see text]) were compared with workloads at lactate thresholds. Several continuous tests were needed to detect the MLSS workload. Agreement and differences among tests were assessed with ANOVA, ICC and Bland-Altman. Reliability of each test was evaluated using ICC, CV and Bland-Altman plots., Results: Workloads at lactate threshold (LT) and LT+2.0 mMol·L-1 matched the ones for VT1 and VT2, respectively (p = 0.147 and 0.539; r = 0.72 and 0.80; Bias = -13.6 and 2.8, respectively). Furthermore, workload at LT+0.5 mMol·L-1 coincided with MLSS workload (p = 0.449; r = 0.78; Bias = -4.5). Lactate threshold tests had high reliability (CV = 3.4-3.7%; r = 0.85-0.89; Bias = -2.1-3.0) except for DMAX method (CV = 10.3%; r = 0.57; Bias = 15.4). Ventilatory thresholds show high reliability (CV = 1.6%-3.5%; r = 0.90-0.96; Bias = -1.8-2.9) except for RER = 1 and V-Slope (CV = 5.0-6.4%; r = 0.79; Bias = -5.6-12.4)., Conclusions: Lactate threshold tests can be a valid and reliable alternative to ventilatory thresholds to identify the workloads at the transition from aerobic to anaerobic metabolism., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2016
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18. The PHQ-PD as a Screening Tool for Panic Disorder in the Primary Care Setting in Spain.
- Author
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Muñoz-Navarro R, Cano-Vindel A, Wood CM, Ruíz-Rodríguez P, Medrano LA, Limonero JT, Tomás-Tomás P, Gracia-Gracia I, Dongil-Collado E, and Iruarrizaga MI
- Subjects
- Adolescent, Adult, Aged, Female, Humans, Male, Middle Aged, Spain, Young Adult, Mass Screening methods, Panic Disorder diagnosis, Primary Health Care, Surveys and Questionnaires
- Abstract
Introduction: Panic disorder is a common anxiety disorder and is highly prevalent in Spanish primary care centres. The use of validated tools can improve the detection of panic disorder in primary care populations, thus enabling referral for specialized treatment. The aim of this study is to determine the accuracy of the Patient Health Questionnaire-Panic Disorder (PHQ-PD) as a screening and diagnostic tool for panic disorder in Spanish primary care centres., Method: We compared the psychometric properties of the PHQ-PD to the reference standard, the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I) interview. General practitioners referred 178 patients who completed the entire PHQ test, including the PHQ-PD, to undergo the SCID-I. The sensitivity, specificity, positive and negative predictive values and positive and negative likelihood ratios of the PHQ-PD were assessed., Results: The operating characteristics of the PHQ-PD are moderate. The best cut-off score was 5 (sensitivity .77, specificity .72). Modifications to the questionnaire's algorithms improved test characteristics (sensitivity .77, specificity .72) compared to the original algorithm. The screening question alone yielded the highest sensitivity score (.83)., Conclusion: Although the modified algorithm of the PHQ-PD only yielded moderate results as a diagnostic test for panic disorder, it was better than the original. Using only the first question of the PHQ-PD showed the best psychometric properties (sensitivity). Based on these findings, we suggest the use of the screening questions for screening purposes and the modified algorithm for diagnostic purposes.
- Published
- 2016
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19. Effect of Dietary Docosahexaenoic Acid Supplementation on the Participation of Vasodilator Factors in Aorta from Orchidectomized Rats.
- Author
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Villalpando DM, Navarro R, Del Campo L, Largo C, Muñoz D, Tabernero M, Baeza R, Otero C, García HS, and Ferrer M
- Subjects
- Animals, Antioxidants metabolism, Aorta metabolism, Blood Pressure drug effects, Diet methods, Dietary Supplements, Fatty Acids pharmacology, Fatty Acids, Omega-3 pharmacology, Male, Nitric Oxide metabolism, Orchiectomy methods, Plant Oils pharmacology, Prostaglandins metabolism, Rats, Rats, Sprague-Dawley, Reactive Oxygen Species metabolism, Sunflower Oil, Aorta drug effects, Docosahexaenoic Acids pharmacology, Vasodilation drug effects, Vasodilator Agents pharmacology
- Abstract
Benefits of n-3 polyunsaturated fatty acids (PUFAs) against cardiovascular diseases have been reported. Vascular tone regulation is largely mediated by endothelial factors whose release is modulated by sex hormones. Since the incidence of cardiovascular pathologies has been correlated with decreased levels of sex hormones, the aim of this study was to analyze whether a diet supplemented with the specific PUFA docosahexaenoic acid (DHA) could prevent vascular changes induced by an impaired gonadal function. For this purpose, control and orchidectomized rats were fed with a standard diet supplemented with 5% (w/w) sunflower oil or with 3% (w/w) sunflower oil plus 2% (w/w) DHA. The lipid profile, the blood pressure, the production of prostanoids and nitric oxide (NO), and the redox status of biological samples from control and orchidectomized rats, fed control or DHA-supplemented diet, were analyzed. The vasodilator response and the contribution of NO, prostanoids and hyperpolarizing mechanisms were also studied. The results showed that orchidectomy negatively affected the lipid profile, increased the production of prostanoids and reactive oxygen species (ROS), and decreased NO production and the antioxidant capacity, as well as the participation of hyperpolarizing mechanisms in the vasodilator responses. The DHA-supplemented diet of the orchidectomized rats decreased the release of prostanoids and ROS, while increasing NO production and the antioxidant capacity, and it also improved the lipid profile. Additionally, it restored the participation of hyperpolarizing mechanisms by activating potassium. Since the modifications induced by the DHA-supplemented diet were observed in the orchidectomized, but not in the healthy group, DHA seems to exert cardioprotective effects in physiopathological situations in which vascular dysfunction exists.
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- 2015
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20. Albumin antioxidant response to stress in diabetic nephropathy progression.
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Medina-Navarro R, Corona-Candelas I, Barajas-González S, Díaz-Flores M, and Durán-Reyes G
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- Adult, Aged, Disease Progression, Female, Glomerular Filtration Rate physiology, Humans, Linear Models, Male, Middle Aged, Models, Biological, Oxidative Stress radiation effects, Ultraviolet Rays, Albumins metabolism, Antioxidants metabolism, Diabetic Nephropathies metabolism
- Abstract
Background: A new component of the protein antioxidant capacity, designated Response Surplus (RS), was recently described. A major feature of this component is the close relationship between protein antioxidant capacity and molecular structure. Oxidative stress is associated with renal dysfunction in patients with renal failure, and plasma albumin is the target of massive oxidation in nephrotic syndrome and diabetic nephropathy. The aim of the present study was to explore the albumin redox state and the RS component of human albumin isolated from diabetic patients with progressive renal damage., Methods/principal Findings: Serum aliquots were collected and albumin isolated from 125 diabetic patients divided into 5 groups according to their estimated glomerular filtration rate (GFR). In addition to clinical and biochemical variables, the albumin redox state, including antioxidant capacity, thiol group content, and RS component, were evaluated. The albumin antioxidant capacity and thiol group content were reciprocally related to the RS component in association with GFR reduction. The GFR decline and RS component were significantly negatively correlated (R = -0.83, p<0.0001). Age, creatinine, thiol groups, and antioxidant capacity were also significantly related to the GFR decline (R = -0.47, p < 0.001; R = -0.68, p<0.0001; R = 0.44, p < 0.001; and R = 0.72, p < 0.0001)., Conclusion/significance: The response of human albumin to stress in relation to the progression of diabetic renal disease was evaluated. The findings confirm that the albumin molecular structure is closely related to its redox state, and is a key factor in the progression of diabetes nephropathy.
- Published
- 2014
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21. Validity of hydration non-invasive indices during the weightcutting and official weigh-in for Olympic combat sports.
- Author
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Fernández-Elías VE, Martínez-Abellán A, López-Gullón JM, Morán-Navarro R, Pallarés JG, De la Cruz-Sánchez E, and Mora-Rodriguez R
- Subjects
- Adolescent, Adult, Boxing, Dehydration diagnosis, Dehydration physiopathology, Female, Humans, Male, Osmolar Concentration, Sports, Thirst physiology, Urinalysis, Wrestling, Athletes, Dehydration urine, Weight Loss
- Abstract
Background: In Olympic combat sports, weight cutting is a common practice aimed to take advantage of competing in weight divisions below the athlete's normal weight. Fluid and food restriction in combination with dehydration (sauna and/or exercise induced profuse sweating) are common weight cut methods. However, the resultant hypohydration could adversely affect health and performance outcomes., Purpose: The aim of this study is to determine which of the routinely used non-invasive measures of dehydration best track urine osmolality, the gold standard non-invasive test., Method: Immediately prior to the official weigh-in of three National Championships, the hydration status of 345 athletes of Olympic combat sports (i.e., taekwondo, boxing and wrestling) was determined using five separate techniques: i) urine osmolality (UOSM), ii) urine specific gravity (USG), iii) urine color (UCOL), iv) bioelectrical impedance analysis (BIA), and v) thirst perception scale (TPS). All techniques were correlated with UOSM divided into three groups: euhydrated (G1; UOSM 250-700 mOsm · kg H2O(-1)), dehydrated (G2; UOSM 701-1080 mOsm · kg H2O(-1)), and severely dehydrated (G3; UOSM 1081-1500 mOsm · kg H2O(-1))., Results: We found a positive high correlation between the UOSM and USG (r = 0.89: p = 0.000), although this relationship lost strength as dehydration increased (G1 r = 0.92; G2 r = 0.73; and G3 r = 0.65; p = 0.000). UCOL showed a moderate although significant correlation when considering the whole sample (r = 0.743: p = 0.000) and G1 (r = 0.702: p = 0.000) but low correlation for the two dehydrated groups (r = 0.498-0.398). TPS and BIA showed very low correlation sizes for all groups assessed., Conclusion: In a wide range of pre-competitive hydration status (UOSM 250-1500 mOsm · kg H2O(-1)), USG is highly associated with UOSM while being a more affordable and easy to use technique. UCOL is a suitable tool when USG is not available. However, BIA or TPS are not sensitive enough to detect hypohydration at official weight-in before an Olympic combat championship.
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- 2014
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22. Ovariectomy increases the participation of hyperpolarizing mechanisms in the relaxation of rat aorta.
- Author
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Sagredo A, del Campo L, Martorell A, Navarro R, Martín MC, Blanco-Rivero J, and Ferrer M
- Subjects
- Animals, Aorta physiology, Catalase genetics, Catalase metabolism, Cyclic GMP-Dependent Protein Kinases genetics, Cyclic GMP-Dependent Protein Kinases metabolism, Enzyme Inhibitors pharmacology, Female, Gene Expression drug effects, Guanylate Cyclase genetics, Guanylate Cyclase metabolism, Hydrogen Peroxide metabolism, NG-Nitroarginine Methyl Ester pharmacology, Nitric Oxide metabolism, Nitric Oxide Synthase Type III genetics, Nitric Oxide Synthase Type III metabolism, Oxadiazoles pharmacology, Potassium Chloride pharmacology, Quinoxalines pharmacology, Rats, Rats, Sprague-Dawley, Superoxide Dismutase genetics, Superoxide Dismutase metabolism, Tissue Culture Techniques, Acetylcholine pharmacology, Aorta drug effects, Ovariectomy, Vasodilation drug effects, Vasodilator Agents pharmacology
- Abstract
This study examines the downstream NO release pathway and the contribution of different vasodilator mediators in the acetylcholine-induced response in rat aorta 5-months after the loss of ovarian function. Aortic segments from ovariectomized and control female Sprague-Dawley rats were used to measure: the levels of superoxide anion, the superoxide dismutases (SODs) activity, the cGMP formation, the cGMP-dependent protein kinase (PKG) activity and the involvement of NO, cGMP, hydrogen peroxide and hyperpolarizing mechanisms in the ACh-induced relaxation. The results showed that ovariectomy did not alter ACh-induced relaxation; incubation with L-NAME, a NO synthase inhibitor, decreased the ACh-induced response to a lesser extent in aorta from ovariectomized than from control rats, while ODQ, a guanylate cyclase inhibitor, decreased that response to a similar extent; the blockade of hyperpolarizing mechanisms, by precontracting arteries with KCl, decreased the ACh-induced response to a greater extent in aortas from ovariectomized than those from control rats; catalase, that decomposes hydrogen peroxide, decreased the ACh-induced response only in aorta from ovariectomized rats. In addition, ovariectomy increased superoxide anion levels and SODs activity, decreased cGMP formation and increased PKG activity. Despite the increased superoxide anion and decreased cGMP in aorta from ovariectomized rats, ACh-induced relaxation is maintained by the existence of hyperpolarizing mechanisms in which hydrogen peroxide participates. The greater contribution of hydrogen peroxide in ACh-induced relaxation is due to increased SOD activity, in an attempt to compensate for increased superoxide anion formation. Increased PKG activity could represent a redundant mechanism to ensure vasodilator function in the aorta of ovariectomized rats.
- Published
- 2013
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23. Human neural stem cell replacement therapy for amyotrophic lateral sclerosis by spinal transplantation.
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Hefferan MP, Galik J, Kakinohana O, Sekerkova G, Santucci C, Marsala S, Navarro R, Hruska-Plochan M, Johe K, Feldman E, Cleveland DW, and Marsala M
- Subjects
- Amyotrophic Lateral Sclerosis physiopathology, Animals, Electric Stimulation, Evoked Potentials, Motor, Humans, Mutation, Rats, Rats, Transgenic, Superoxide Dismutase genetics, Superoxide Dismutase-1, Synapses physiology, Amyotrophic Lateral Sclerosis surgery, Neural Stem Cells transplantation, Spinal Cord surgery, Stem Cell Transplantation
- Abstract
Background: Mutation in the ubiquitously expressed cytoplasmic superoxide dismutase (SOD1) causes an inherited form of Amyotrophic Lateral Sclerosis (ALS). Mutant synthesis in motor neurons drives disease onset and early disease progression. Previous experimental studies have shown that spinal grafting of human fetal spinal neural stem cells (hNSCs) into the lumbar spinal cord of SOD1(G93A) rats leads to a moderate therapeutical effect as evidenced by local α-motoneuron sparing and extension of lifespan. The aim of the present study was to analyze the degree of therapeutical effect of hNSCs once grafted into the lumbar spinal ventral horn in presymptomatic immunosuppressed SOD1(G93A) rats and to assess the presence and functional integrity of the descending motor system in symptomatic SOD1(G93A) animals., Methods/principal Findings: Presymptomatic SOD1(G93A) rats (60-65 days old) received spinal lumbar injections of hNSCs. After cell grafting, disease onset, disease progression and lifespan were analyzed. In separate symptomatic SOD1(G93A) rats, the presence and functional conductivity of descending motor tracts (corticospinal and rubrospinal) was analyzed by spinal surface recording electrodes after electrical stimulation of the motor cortex. Silver impregnation of lumbar spinal cord sections and descending motor axon counting in plastic spinal cord sections were used to validate morphologically the integrity of descending motor tracts. Grafting of hNSCs into the lumbar spinal cord of SOD1(G93A) rats protected α-motoneurons in the vicinity of grafted cells, provided transient functional improvement, but offered no protection to α-motoneuron pools distant from grafted lumbar segments. Analysis of motor-evoked potentials recorded from the thoracic spinal cord of symptomatic SOD1(G93A) rats showed a near complete loss of descending motor tract conduction, corresponding to a significant (50-65%) loss of large caliber descending motor axons., Conclusions/significance: These data demonstrate that in order to achieve a more clinically-adequate treatment, cell-replacement/gene therapy strategies will likely require both spinal and supraspinal targets.
- Published
- 2012
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24. Peripheral blood invariant natural killer T cells of pig-tailed macaques.
- Author
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Li X, Polacino P, Garcia-Navarro R, Hu SL, and Tsuji M
- Subjects
- Animals, CD4-Positive T-Lymphocytes metabolism, CD8-Positive T-Lymphocytes metabolism, Flow Cytometry, Interferon-gamma metabolism, Leukocytes, Mononuclear metabolism, Tumor Necrosis Factor-alpha metabolism, Macaca immunology, Natural Killer T-Cells metabolism
- Abstract
In humans, invariant natural killer T (iNKT) cells represent a small but significant population of peripheral blood mononuclear cells (PBMCs) with a high degree of variability. In this study, pursuant to our goal of identifying an appropriate non-human primate model suitable for pre-clinical glycolipid testing, we evaluated the percentage and function of iNKT cells in the peripheral blood of pig-tailed macaques. First, using a human CD1d-tetramer loaded with α-GalCer (α-GalCer-CD1d-Tet), we found that α-GalCer-CD1d-Tet(+) CD3(+) iNKT cells make up 0.13% to 0.4% of pig-tailed macaque PBMCs, which are comparable to the percentage of iNKT cells found in human PBMCs. Second, we observed that a large proportion of Vα24(+)CD3(+) cells are α-GalCer-CD1d-Tet(+)CD3(+) iNKT cells, which primarily consist of either the CD4(+) or CD8(+) subpopulation. Third, we found that pig-tailed macaque iNKT cells produce IFN-γ in response to α-GalCer, as shown by ELISpot assay and intracellular cytokine staining (ICCS), as well as TNF-α, as shown by ICCS, indicating that these iNKT cells are fully functional. Interestingly, the majority of pig-tailed macaque iNKT cells that secrete IFN-γ are CD8(+)iNKT cells. Based on these findings, we conclude that the pig-tailed macaques exhibit potential as a non-human animal model for the pre-clinical testing of iNKT-stimulating glycolipids.
- Published
- 2012
- Full Text
- View/download PDF
25. The ROCK inhibitor Y-27632 improves recovery of human embryonic stem cells after fluorescence-activated cell sorting with multiple cell surface markers.
- Author
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Emre N, Vidal JG, Elia J, O'Connor ED, Paramban RI, Hefferan MP, Navarro R, Goldberg DS, Varki NM, Marsala M, and Carson CT
- Subjects
- Biomarkers metabolism, Cell Culture Techniques, Cell Differentiation drug effects, Embryonic Stem Cells metabolism, Humans, Karyotyping, Amides pharmacology, Embryonic Stem Cells cytology, Embryonic Stem Cells drug effects, Flow Cytometry methods, Protein Kinase Inhibitors pharmacology, Pyridines pharmacology, rho-Associated Kinases antagonists & inhibitors
- Abstract
Background: Due to the inherent sensitivity of human embryonic stem cells (hESCs) to manipulations, the recovery and survival of hESCs after fluorescence-activated cell sorting (FACS) can be low. Additionally, a well characterized and robust methodology for performing FACS on hESCs using multiple-cell surface markers has not been described. The p160-Rho-associated coiled kinase (ROCK) inhibitor, Y-27632, previously has been identified as enhancing survival of hESCs upon single-cell dissociation, as well as enhancing recovery from cryopreservation. Here we examined the application of Y-27632 to hESCs after FACS to improve survival in both feeder-dependent and feeder-independent growth conditions., Methodology/principal Findings: HESCs were sorted using markers for SSEA-3, TRA-1-81, and SSEA-1. Cells were plated after sorting for 24 hours in either the presence or the absence of Y-27632. In both feeder-dependent and feeder-independent conditions, cell survival was greater when Y-27632 was applied to the hESCs after sort. Specifically, treatment of cells with Y-27632 improved post-sort recovery up to four fold. To determine the long-term effects of sorting with and without the application of Y-27632, hESCs were further analyzed. Specifically, hESCs sorted with and without the addition of Y-27632 retained normal morphology, expressed hESC-specific markers as measured by immunocytochemistry and flow cytometry, and maintained a stable karyotype. In addition, the hESCs could differentiate into three germ layers in vitro and in vivo in both feeder-dependent and feeder-independent growth conditions., Conclusions/significance: The application of Y-27632 to hESCs after cell sorting improves cell recovery with no observed effect on pluripotency, and enables the consistent recovery of hESCs by FACS using multiple surface markers. This improved methodology for cell sorting of hESCs will aid many applications such as removal of hESCs from secondary cell types, identification and isolation of stem cell subpopulations, and generation of single cell clones. Finally, these results demonstrate an additional application of ROCK inhibition to hESC research.
- Published
- 2010
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26. Protein antioxidant response to the stress and the relationship between molecular structure and antioxidant function.
- Author
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Medina-Navarro R, Durán-Reyes G, Díaz-Flores M, and Vilar-Rojas C
- Subjects
- Fluorescence, Reactive Oxygen Species metabolism, Ultraviolet Rays, Antioxidants metabolism, Proteins metabolism
- Abstract
Background: Proteins have long been considered a principal target for oxidants as a result of their abundance in biological systems. However, there is increasing evidence about the significant antioxidant activity in proteins such as albumin. It is leading to new concepts that even consider albumin not only as an antioxidant but as the major antioxidant in plasma known to be exposed to continuous oxidative stress. Evidence presented here establishes a previously unrecognized relationship between proteins' antioxidant capacity and structural stress., Methodology/principal Findings: A chemiluminiscence based antioxidant assay was achieved to quantify the antioxidant capacity of albumin and other proteins. The capabilities of proteins as antioxidants were presented, but in addition a new and powerful component of the protein antioxidant capacity was discovered. The intrinsic component, designated as Response Surplus (RS), represents a silent reserve of antioxidant power that awakens when proteins face a structural perturbation (stressor) such as temperature, short wave UV light, the same reactive oxygen species, and more extreme changes like glucose or aldehyde-mediated structural modifications. The work also highlights the importance of structural changes in protein antioxidant properties and the participation of sulfhydryl groups (SHs) in the RS antioxidant component. Based on recent evidence about the SH group chemistry, a possible model for explaining RS is proposed., Conclusions/significance: The data presented show the significant antioxidant behavior of proteins and demonstrate the existence of a previously unrecognized antioxidant response to the stress. Several implications, including changes in elementary concepts about antioxidants and protein function, should emerge from here.
- Published
- 2010
- Full Text
- View/download PDF
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