Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 132
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Sensors (Basel) ; 23(18)2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37765868

RESUMEN

Farm tractors have become a key part of daily routine agriculture, converting complex and time-consuming tasks into tasks that are easier to perform and less dependent on human labor, contributing directly to increasing the economic value generated by this activity sector, either by increasing the productivity or by making certain agricultural crops viable, which otherwise would not be sustainable. However, despite all the advantages, accidents with this type of equipment are common, often with critical and sometimes fatal consequences. The evolution of safety requirements of these machines has occurred at a good level; however, a significant part of the agricultural tractors in use are older models that do not have such solutions. Even in the new models, which contain such solutions, these are not always correctly used, and it is even common that they are turned off or simply not used at all. It is therefore natural that accidents continue to occur, a situation that is aggravated by other factors. Lack of situational awareness of the operators, which can result from advanced age, inadequate training, reduced sensitivity/respect for safety rules, or working on irregular terrain like mountainous areas, contribute to high-risk contexts that end in the loss of human life. The consequences of such accidents are clearly aggravated by the time it takes to assist the victims-either because accidents are simply not identified/reported immediately, or by the time it takes to locate and provide help to the victims. This is a scenario that is more common in mountainous regions and regions with low population density. The current paper, using NB-IoT, a set of sensors, and a web application, presents a conceptual toolset conceived to prevent accidents and minimize consequences (human and material) that can be applied to old and new farm tractors. The development was carried out taking the characterization of the farmers and the land in the region in which the authors' research institution is located into account, which has the highest rate of fatal accidents with agricultural tractors in the country; it is a region of mountainous with a very low population density.


Asunto(s)
Accidentes , Agricultura , Humanos , Granjas , Densidad de Población , Concienciación
2.
Transgenic Res ; 31(2): 249-268, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35201538

RESUMEN

Isoprenoids are natural products derived from isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP). In plants, these precursors are synthesized via the cytosolic mevalonate (MVA) and plastidial methylerythritol phosphate (MEP) pathways. The regulation of these pathways must therefore be understood in detail to develop effective strategies for isoprenoid metabolic engineering. We hypothesized that the strict regulation of the native MVA pathway could be circumvented by expressing an ectopic plastidial MVA pathway that increases the accumulation of IPP and DMAPP in plastids. We therefore introduced genes encoding the plastid-targeted enzymes HMGS, tHMGR, MK, PMK and MVD and the nuclear-targeted transcription factor WR1 into rice and evaluated the impact of their endosperm-specific expression on (1) endogenous metabolism at the transcriptomic and metabolomic levels, (2) the synthesis of phytohormones, carbohydrates and fatty acids, and (3) the macroscopic phenotype including seed morphology. We found that the ectopic plastidial MVA pathway enhanced the expression of endogenous cytosolic MVA pathway genes while suppressing the native plastidial MEP pathway, increasing the production of certain sterols and tocopherols. Plants carrying the ectopic MVA pathway only survived if WR1 was also expressed to replenish the plastid acetyl-CoA pool. The transgenic plants produced higher levels of fatty acids, abscisic acid, gibberellins and lutein, reflecting crosstalk between phytohormones and secondary metabolism.


Asunto(s)
Oryza , Ácidos Grasos , Ácido Mevalónico/metabolismo , Oryza/genética , Oryza/metabolismo , Reguladores del Crecimiento de las Plantas , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Terpenos/metabolismo
3.
Inflamm Res ; 71(5-6): 591-602, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35471601

RESUMEN

BACKGROUND: Inflammation is a common feature in the pathogenesis of chronic kidney disease (CKD), regardless of the disease cause. Our aim was to evaluate the potential of several inflammatory biomarkers in CKD diagnosis and staging. METHODS: A total of 24 healthy controls and 92 pre-dialysis CKD patients with diverse etiologies, were enrolled in this study and grouped according to their CKD stage. We analysed the circulating levels of inflammatory molecules, C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), tumor necrosis factor receptor 2 (TNFR2), pentraxin 3 (PTX3) and leptin, as well as the hemogram. We studied their association with parameters of kidney function and kidney injury, to evaluate their potential as early markers of the disease and/or of its worsening, as well as their interplay. RESULTS: Compared to controls, patients in CKD stages 1-2 presented significantly higher IL-6 and TNFR2 levels, and higher neutrophil-to-lymphocyte ratio. All inflammatory cytokines and acute-phase proteins showed a trend to increase up to stage 3, stabilizing or declining thereafter, save for TNFR2, which steadily increased from stage to stage. All inflammatory molecules, apart from PTX3, were negatively and significantly correlated with eGFR, with a remarkable value for TNFR2 (r = - 0.732, p < 0.001). CONCLUSION: TNFR2 might be useful for an early detection of CKD, as well as for disease staging/worsening. Still, the potential value of this biomarker in disease progression warrants further investigation.


Asunto(s)
Receptores Tipo II del Factor de Necrosis Tumoral , Insuficiencia Renal Crónica , Biomarcadores/metabolismo , Humanos , Inflamación/metabolismo , Interleucina-6/metabolismo , Riñón/metabolismo , Receptores Tipo II del Factor de Necrosis Tumoral/metabolismo , Insuficiencia Renal Crónica/metabolismo
4.
Clin Transplant ; 36(4): e14585, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34997797

RESUMEN

Vaccination is a promising strategy to control the ongoing pandemic; however, solid organ recipients tend to develop a weaker immune response to vaccination. Anti-spike SARS-CoV-2 antibodies titers were measured 2-4 weeks post-vaccination completion in 131 KT patients without previous infection. Demographic, clinical, and laboratorial parameters were analyzed to identify which factors contributed to seroconversion. Factors that influenced seroconversion, that occurred in 76 patients (58%), were longer time post-transplant, immunosuppression without an antiproliferative drug and vaccination with mRNA vaccines. Patients who received mRNA vaccines had significantly higher rates of seroconversion compared with adenovirus vector vaccines (67% vs 33%, P < .001) and higher anti-spike IgG titers. These findings reinforce the need to discuss the vaccination strategy in this population, including a third dose with a mRNA vaccine.


Asunto(s)
COVID-19 , Trasplante de Riñón , Anticuerpos Antivirales , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Trasplante de Riñón/efectos adversos , SARS-CoV-2 , Receptores de Trasplantes , Vacunación , Vacunas Sintéticas , Vacunas de ARNm
5.
J Perinat Med ; 50(2): 185-191, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-34727592

RESUMEN

OBJECTIVES: Maternal and fetal complications can occur in pregnant kidney transplant recipients. Since these are high-risk pregnancies, they require a multidisciplinary follow-up to prematurely detect adverse events. Identifying factors that would affect fetal, maternal and graft outcomes is essential to further stratify the risk of pregnant kidney transplant recipients. METHODS: All pregnancies in kidney transplant recipients followed in a single center for 30 years were included. Data included previous transplant information and blood and urine tests performed before pregnancy. Impact of graft function on fetal, maternal and graft outcomes was evaluated. RESULTS: There were 41 pregnancies among 34 patients. Mean gestational age of 35 ± 3 weeks. Caesarean section was performed in 69.4% of patients. Five pregnancies were unsuccessful (12.2%). Four patients suffered an acute graft dysfunction (9.8%) and 12 (29.3%) had a serious maternal hypertensive disorder (preeclampsia, eclampsia or HELLP syndrome). Graft function before pregnancy showed significant correlation with adverse outcomes. CONCLUSIONS: A proteinuria >669 mg/g, serum creatinine >1.75 mg/dL and glomerular filtration rate <36.2 mL/min/1.73 m2 before pregnancy were correlated to graft dysfunction during pregnancy. Similar values of proteinuria were also associated with a risk of maternal hypertensive disorders and pregnancy failure. Therefore, in patients with proteinuria and graft dysfunction, follow-up should be stricter to quickly detect complications.


Asunto(s)
Trasplante de Riñón , Preeclampsia , Complicaciones del Embarazo , Cesárea/efectos adversos , Creatinina , Femenino , Humanos , Lactante , Riñón , Trasplante de Riñón/efectos adversos , Embarazo , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/etiología , Resultado del Embarazo/epidemiología
6.
Int J Mol Sci ; 23(21)2022 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-36361939

RESUMEN

Friedreich's ataxia is a neurodegenerative disease caused by mutations in the frataxin gene. Frataxin homologues, including bacterial CyaY proteins, can be found in most species and play a fundamental role in mitochondrial iron homeostasis, either promoting iron assembly into metaloproteins or contributing to iron detoxification. While several lines of evidence suggest that eukaryotic frataxins are more effective than bacterial ones in iron detoxification, the residues involved in this gain of function are unknown. In this work, we analyze conservation of amino acid sequence and protein structure among frataxins and CyaY proteins to identify four highly conserved residue clusters and group them into potential functional clusters. Clusters 1, 2, and 4 are present in eukaryotic frataxins and bacterial CyaY proteins. Cluster 3, containing two serines, a tyrosine, and a glutamate, is only present in eukaryotic frataxins and on CyaY proteins from the Rickettsia genus. Residues from cluster 3 are blocking a small cavity of about 40 Å present in E. coli's CyaY. The function of this cluster is unknown, but we hypothesize that its tyrosine may contribute to prevent formation of reactive oxygen species during iron detoxification. This cluster provides an example of gain of function during evolution in a protein involved in iron homeostasis, as our results suggests that Cluster 3 was present in the endosymbiont ancestor of mitochondria and was conserved in eukaryotic frataxins.


Asunto(s)
Proteínas de Unión a Hierro , Enfermedades Neurodegenerativas , Rickettsia , Humanos , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Eucariontes/metabolismo , Ataxia de Friedreich/genética , Ataxia de Friedreich/metabolismo , Hierro/metabolismo , Proteínas de Unión a Hierro/química , Proteínas de Unión a Hierro/metabolismo , Rickettsia/metabolismo , Tirosina/metabolismo , Mitocondrias/metabolismo , Mitocondrias/microbiología , Frataxina
7.
Bioinformatics ; 36(3): 976-977, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31504183

RESUMEN

SUMMARY: EasyModel is a new user-friendly web application that contains ready-for-simulation versions of the BioModels Database, and allows for the intuitive creation of new models. Its main target audience is the experimental biologist and students of bioinformatics or systems biology without programming skills. Expert users can also benefit from it by implementing basic models quickly and downloading the code for further tailoring. AVAILABILITY AND IMPLEMENTATION: Freely available on the web at https://easymodel.udl.cat. Implementation is described in its own section.


Asunto(s)
Programas Informáticos , Biología de Sistemas , Biología Computacional , Bases de Datos Factuales , Humanos , Internet , Modelos Biológicos
9.
Int J Mol Sci ; 22(1)2020 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-33375198

RESUMEN

The prevalence of chronic kidney disease (CKD) is increasing worldwide, and the mortality rate continues to be unacceptably high. The biomarkers currently used in clinical practice are considered relevant when there is already significant renal impairment compromising the early use of potentially successful therapeutic interventions. More sensitive and specific biomarkers to detect CKD earlier on and improve patients' prognoses are an important unmet medical need. The aim of this review is to summarize the recent literature on new promising early CKD biomarkers of renal function, tubular lesions, endothelial dysfunction and inflammation, and on the auspicious findings from metabolomic studies in this field. Most of the studied biomarkers require further validation in large studies and in a broad range of populations in order to be implemented into routine CKD management. A panel of biomarkers, including earlier biomarkers of renal damage, seems to be a reasonable approach to be applied in clinical practice to allow earlier diagnosis and better disease characterization based on the underlying etiologic process.


Asunto(s)
Biomarcadores/análisis , Diagnóstico Precoz , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/terapia , Progresión de la Enfermedad , Glucuronidasa/análisis , Humanos , Oxidorreductasas Intramoleculares/análisis , Proteínas Klotho , Lipocalinas/análisis , Pronóstico , Sensibilidad y Especificidad , Microglobulina beta-2/análisis
10.
Biochemistry ; 58(31): 3365-3376, 2019 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-31259528

RESUMEN

Rubisco is the primary carboxylase of the Calvin cycle, the most abundant enzyme in the biosphere, and one of the best-characterized enzymes. On the basis of correlations between Rubisco kinetic parameters, it is widely posited that constraints embedded in the catalytic mechanism enforce trade-offs between CO2 specificity, SC/O, and maximum carboxylation rate, kcat,C. However, the reasoning that established this view was based on data from ≈20 organisms. Here, we re-examine models of trade-offs in Rubisco catalysis using a data set from ≈300 organisms. Correlations between kinetic parameters are substantially attenuated in this larger data set, with the inverse relationship between kcat,C and SC/O being a key example. Nonetheless, measured kinetic parameters display extremely limited variation, consistent with a view of Rubisco as a highly constrained enzyme. More than 95% of kcat,C values are between 1 and 10 s-1, and no measured kcat,C exceeds 15 s-1. Similarly, SC/O varies by only 30% among Form I Rubiscos and <10% among C3 plant enzymes. Limited variation in SC/O forces a strong positive correlation between the catalytic efficiencies (kcat/KM) for carboxylation and oxygenation, consistent with a model of Rubisco catalysis in which increasing the rate of addition of CO2 to the enzyme-substrate complex requires an equal increase in the O2 addition rate. Altogether, these data suggest that Rubisco evolution is tightly constrained by the physicochemical limits of CO2/O2 discrimination.


Asunto(s)
Modelos Biológicos , Ribulosa-Bifosfato Carboxilasa/metabolismo , Dióxido de Carbono/metabolismo , Cinética , Oxígeno/metabolismo , Termodinámica
11.
Behav Res Methods ; 50(2): 744-758, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28540511

RESUMEN

We describe the Multilanguage Written Picture Naming Dataset. This gives trial-level data and time and agreement norms for written naming of the 260 pictures of everyday objects that compose the colorized Snodgrass and Vanderwart picture set (Rossion & Pourtois in Perception, 33, 217-236, 2004). Adult participants gave keyboarded responses in their first language under controlled experimental conditions (N = 1,274, with subsamples responding in Bulgarian, Dutch, English, Finnish, French, German, Greek, Icelandic, Italian, Norwegian, Portuguese, Russian, Spanish, and Swedish). We measured the time to initiate a response (RT) and interkeypress intervals, and calculated measures of name and spelling agreement. There was a tendency across all languages for quicker RTs to pictures with higher familiarity, image agreement, and name frequency, and with higher name agreement. Effects of spelling agreement and effects on output rates after writing onset were present in some, but not all, languages. Written naming therefore shows name retrieval effects that are similar to those found in speech, but our findings suggest the need for cross-language comparisons as we seek to understand the orthographic retrieval and/or assembly processes that are specific to written output.


Asunto(s)
Lenguaje , Reconocimiento en Psicología , Percepción Visual/fisiología , Adulto , Europa (Continente) , Femenino , Percepción de Forma/fisiología , Humanos , Masculino , Psicolingüística/métodos , Tiempo de Reacción/fisiología , Escritura , Adulto Joven
12.
Plant J ; 87(5): 455-71, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27155093

RESUMEN

Plant synthetic biology is still in its infancy. However, synthetic biology approaches have been used to manipulate and improve the nutritional and health value of staple food crops such as rice, potato and maize. With current technologies, production yields of the synthetic nutrients are a result of trial and error, and systematic rational strategies to optimize those yields are still lacking. Here, we present a workflow that combines gene expression and quantitative metabolomics with mathematical modeling to identify strategies for increasing production yields of nutritionally important carotenoids in the seed endosperm synthesized through alternative biosynthetic pathways in synthetic lines of white maize, which is normally devoid of carotenoids. Quantitative metabolomics and gene expression data are used to create and fit parameters of mathematical models that are specific to four independent maize lines. Sensitivity analysis and simulation of each model is used to predict which gene activities should be further engineered in order to increase production yields for carotenoid accumulation in each line. Some of these predictions (e.g. increasing Zmlycb/Gllycb will increase accumulated ß-carotenes) are valid across the four maize lines and consistent with experimental observations in other systems. Other predictions are line specific. The workflow is adaptable to any other biological system for which appropriate quantitative information is available. Furthermore, we validate some of the predictions using experimental data from additional synthetic maize lines for which no models were developed.


Asunto(s)
Carotenoides/metabolismo , Modelos Teóricos , Zea mays/metabolismo , Biología Computacional/métodos , Metabolómica/métodos
14.
Plant J ; 77(3): 464-75, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24267591

RESUMEN

We have developed an assay based on rice embryogenic callus for rapid functional characterization of metabolic genes. We validated the assay using a selection of well-characterized genes with known functions in the carotenoid biosynthesis pathway, allowing rapid visual screening of callus phenotypes based on tissue color. We then used the system to identify the functions of two uncharacterized genes: a chemically synthesized ß-carotene ketolase gene optimized for maize codon usage, and a wild-type Arabidopsis thaliana ortholog of the cauliflower Orange gene. In contrast to previous reports (Lopez, A.B., Van Eck, J., Conlin, B.J., Paolillo, D.J., O'Neill, J. and Li, L. () J. Exp. Bot. 59, 213-223; Lu, S., Van Eck, J., Zhou, X., Lopez, A.B., O'Halloran, D.M., Cosman, K.M., Conlin, B.J., Paolillo, D.J., Garvin, D.F., Vrebalov, J., Kochian, L.V., Küpper, H., Earle, E.D., Cao, J. and Li, L. () Plant Cell 18, 3594-3605), we found that the wild-type Orange allele was sufficient to induce chromoplast differentiation. We also found that chromoplast differentiation was induced by increasing the availability of precursors and thus driving flux through the pathway, even in the absence of Orange. Remarkably, we found that diverse endosperm-specific promoters were highly active in rice callus despite their restricted activity in mature plants. Our callus system provides a unique opportunity to predict the effect of metabolic engineering in complex pathways, and provides a starting point for quantitative modeling and the rational design of engineering strategies using synthetic biology. We discuss the impact of our data on analysis and engineering of the carotenoid biosynthesis pathway.


Asunto(s)
Arabidopsis/enzimología , Carotenoides/metabolismo , Chlamydomonas reinhardtii/enzimología , Oryza/enzimología , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Vías Biosintéticas , Carotenoides/análisis , Diferenciación Celular , Chlamydomonas reinhardtii/genética , Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genotipo , Ingeniería Metabólica , Metaboloma , Metabolómica , Modelos Teóricos , Oryza/citología , Oryza/genética , Oxigenasas/síntesis química , Oxigenasas/genética , Oxigenasas/metabolismo , Fenotipo , Proteínas de Plantas/síntesis química , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Plastidios/metabolismo , Regiones Promotoras Genéticas/genética , Transferasas/genética , Transferasas/metabolismo , Transgenes
15.
Bioinformatics ; 30(7): 1039-40, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24227678

RESUMEN

MOTIVATION: Chemical named entity recognition is used to automatically identify mentions to chemical compounds in text and is the basis for more elaborate information extraction. However, only a small number of applications are freely available to identify such mentions. Particularly challenging and useful is the identification of International Union of Pure and Applied Chemistry (IUPAC) chemical compounds, which due to the complex morphology of IUPAC names requires more advanced techniques than that of brand names. RESULTS: We present CheNER, a tool for automated identification of systematic IUPAC chemical mentions. We evaluated different systems using an established literature corpus to show that CheNER has a superior performance in identifying IUPAC names specifically, and that it makes better use of computational resources. AVAILABILITY AND IMPLEMENTATION: http://metres.udl.cat/index.php/9-download/4-chener, http://chener.bioinfo.cnio.es/


Asunto(s)
Bases de Datos de Compuestos Químicos , Programas Informáticos , Almacenamiento y Recuperación de la Información
16.
Plant J ; 75(3): 441-55, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23607313

RESUMEN

Carotenoids are a diverse group of tetraterpenoid pigments found in plants, fungi, bacteria and some animals. They play vital roles in plants and provide important health benefits to mammals, including humans. We previously reported the creation of a diverse population of transgenic maize plants expressing various carotenogenic gene combinations and exhibiting distinct metabolic phenotypes. Here we performed an in-depth targeted mRNA and metabolomic analysis of the pathway to characterize the specific impact of five carotenogenic transgenes and their interactions with 12 endogenous genes in four transgenic lines representing distinct genotypes and phenotypes. We reconstructed the temporal profile of the carotenoid pathway during endosperm development at the mRNA and metabolic levels (for total and individual carotenoids), and investigated the impact of transgene expression on the endogenous pathway. These studies enabled us to investigate the extent of any interactions between the introduced transgenic and native partial carotenoid pathways during maize endosperm development. Importantly, we developed a theoretical model that explains these interactions, and our results suggest genetic intervention points that may allow the maize endosperm carotenoid pathway to be engineered in a more effective and predictable manner.


Asunto(s)
Carotenoides/genética , Carotenoides/metabolismo , Plantas Modificadas Genéticamente , Zea mays/genética , Zea mays/metabolismo , Endospermo/crecimiento & desarrollo , Endospermo/metabolismo , Regulación de la Expresión Génica de las Plantas , Ingeniería Genética/métodos , Metaboloma , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Xantófilas/metabolismo
17.
ScientificWorldJournal ; 2014: 967294, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25202745

RESUMEN

Our group developed two biological applications, Biblio-MetReS and Homol-MetReS, accessing the same database of organisms with annotated genes. Biblio-MetReS is a data-mining application that facilitates the reconstruction of molecular networks based on automated text-mining analysis of published scientific literature. Homol-MetReS allows functional (re)annotation of proteomes, to properly identify both the individual proteins involved in the process(es) of interest and their function. It also enables the sets of proteins involved in the process(es) in different organisms to be compared directly. The efficiency of these biological applications is directly related to the design of the shared database. We classified and analyzed the different kinds of access to the database. Based on this study, we tried to adjust and tune the configurable parameters of the database server to reach the best performance of the communication data link to/from the database system. Different database technologies were analyzed. We started the study with a public relational SQL database, MySQL. Then, the same database was implemented by a MapReduce-based database named HBase. The results indicated that the standard configuration of MySQL gives an acceptable performance for low or medium size databases. Nevertheless, tuning database parameters can greatly improve the performance and lead to very competitive runtimes.


Asunto(s)
Biología Computacional/métodos , Bases de Datos Genéticas , Redes y Vías Metabólicas , Programas Informáticos , Modelos Biológicos
18.
Int J Mol Sci ; 15(5): 8979-97, 2014 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-24853130

RESUMEN

Cyclosporin A (CsA), a calcineurin inhibitor, remain the cornerstone of immunosuppressive regimens, regardless of nephrotoxicity, which depends on the duration of drug exposure. The mechanisms and biomarkers underlying the transition from CsA-induced renal dysfunction to nephrotoxicity deserve better elucidation, and would help clinical decisions. This study aimed to clarify these issues, using a rat model of short- and long-term CsA (5 mg/kg bw/day) treatments (3 and 9 weeks, respectively). Renal function was assessed on serum and urine; kidney tissue was used for histopathological characterization and gene and/or protein expression of markers of proliferation, fibrosis and inflammation. In the short-term, creatinine and blood urea nitrogen (BUN) levels increased and clearances decreased, accompanied by glomerular filtration rate (GFR) reduction, but without kidney lesions; at that stage, CsA exposure induced proliferating cell nuclear antigen (PCNA), transforming growth factor beta 1 (TGF-ß1), factor nuclear kappa B (NF-κß) and Tumor Protein P53 (TP53) kidney mRNA up-regulation. In the long-term treatment, renal dysfunction data was accompanied by glomerular and tubulointerstitial lesions, with remarkable kidney mRNA up-regulation of the mammalian target of rapamycin (mTOR) and the antigen identified by monoclonal antibody Ki-67 (Mki67), accompanied by mTOR protein overexpression. Transition from CsA-induced renal dysfunction to nephrotoxicity is accompanied by modification of molecular mechanisms and biomarkers, being mTOR one of the key players for kidney lesion evolution, thus suggesting, by mean of molecular evidences, that early CsA replacement by mTOR inhibitors is indeed the better therapeutic choice to prevent chronic allograft nephropathy.


Asunto(s)
Ciclosporina/toxicidad , Inmunosupresores/toxicidad , Enfermedades Renales/etiología , Riñón/efectos de los fármacos , Animales , Biomarcadores/metabolismo , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Ciclosporina/efectos adversos , Citocinas/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Inmunosupresores/efectos adversos , Mediadores de Inflamación/metabolismo , Riñón/metabolismo , Riñón/fisiopatología , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Masculino , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Regulación hacia Arriba/efectos de los fármacos
19.
Br J Educ Psychol ; 84(Pt 4): 571-90, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24905206

RESUMEN

BACKGROUND: In the field of intelligence research, it has been shown that some people conceive intelligence as a fixed trait that cannot be changed (entity beliefs), whereas others conceive it as a malleable trait that can be developed (incremental beliefs). What about writing? Do people hold similar implicit theories about the nature of their writing ability? Furthermore, are these beliefs likely to influence students' response to a writing intervention? AIMS: We aimed to develop a scale to measure students' implicit theories of writing (pilot study) and to test whether these beliefs influence strategy-instruction effectiveness (intervention study). SAMPLE: In the pilot and intervention studies participated, respectively, 128 and 192 students (Grades 5-6). METHOD: Based on existing instruments that measure self-theories of intelligence, we developed the Implicit Theories of Writing (ITW) scale that was tested with the pilot sample. In the intervention study, 109 students received planning instruction based on the self-regulated strategy development model, whereas 83 students received standard writing instruction. Students were evaluated before, in the middle, and after instruction. RESULTS: ITW's validity was supported by piloting results and their successful cross-validation in the intervention study. In this, intervention students wrote longer and better texts than control students. Moreover, latent growth curve modelling showed that the more the intervention students conceived writing as a malleable skill, the more the quality of their texts improved. CONCLUSION: This research is of educational relevance because it provides a measure to evaluate students' implicit theories of writing and shows their impact on response to intervention.


Asunto(s)
Logro , Aptitud , Cultura , Inteligencia , Estudiantes/psicología , Escritura , Niño , Curriculum , Femenino , Humanos , Masculino , Proyectos Piloto , Enseñanza
20.
Br J Educ Psychol ; 84(Pt 2): 177-93, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24829117

RESUMEN

BACKGROUND: It is well established that the activity of producing a text is a complex one involving three main cognitive processes: Planning, translating, and revising. Although these processes are crucial in skilled writing, beginning and developing writers seem to struggle with them, mainly with planning and revising. AIMS: To trace the development of the high-level writing processes of planning and revising, from Grades 4 to 9, and to examine whether these skills predict writing quality in younger and older students (Grades 4-6 vs. 7-9), after controlling for gender, school achievement, age, handwriting fluency, spelling, and text structure. SAMPLE: Participants were 381 students from Grades 4 to 9 (age 9-15). METHOD: Students were asked to plan and write a story and to revise another story by detecting and correcting mechanical and substantive errors. RESULTS: From Grades 4 to 9, we found a growing trend in students' ability to plan and revise despite the observed decreases and stationary periods from Grades 4 to 5 and 6 to 7. Moreover, whereas younger students' planning and revising skills made no contribution to the quality of their writing, in older students, these high-level skills contributed to writing quality above and beyond control predictors. CONCLUSION: The findings of this study seem to indicate that besides the increase in planning and revising, these skills are not fully operational in school-age children. Indeed, given the contribution of these high-level skills to older students' writing, supplementary instruction and practice should be provided from early on.


Asunto(s)
Creatividad , Escritura , Adolescente , Factores de Edad , Análisis de Varianza , Aptitud , Niño , Femenino , Humanos , Masculino , Técnicas de Planificación , Portugal , Estudiantes/psicología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA