Estudio de las poblaciones celulares Th17 y Thf en la patogenia de la artritis reumatoide

Tesis doctoral inédita, leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de BioquímicaLa artritis reumatoide (AR), es una enfermedad autoinmune sistémica, caracterizada por la inflamación crónica de las articulaciones, la destrucción del cartílago y las erosiones óseas. Numerosos estudios indican que la interleuquina 17 (IL-17) desempeña un papel importante en la patogenia de la AR. Ratones deficientes para IL-17 muestran una forma atenuada de artritis inducida por colágeno y el tratamiento con anti-IL-17 en este mismo modelo murino de AR, se asocia con una reducción significativa de la gravedad. En estudios en humanos, se han observado niveles altos de IL-17 en el líquido sinovial de pacientes con AR y se ha detectado la producción de IL-17 en células T CD4+ de la membrana sinovial de AR. Un porcentaje alterado de las células Th17 ha sido descrito en sangre periférica y líquido sinovial de pacientes con AR, pero hasta la fecha los datos encontrados son contradictorios. Por otro lado, las células B también participan en la patogenia de la AR a través de la producción de autoanticuerpos. Las células T helper foliculares (Thf), promueven la maduración de las células B y la producción de anticuerpos. Estas células juegan un papel importante en la autoinmunidad, se ha descrito un aumento del número células Thf en modelos murinos de artritis inflamatoria. Las células Thf clásicas se encuentran en los órganos linfoides secundarios. Varios autores han descrito poblaciones de células T CD4+CXCR5+ circulantes que muestran características fenotípicas y funcionales de células Thf. El aumento de la frecuencias de estos homólogos circulantes de células Thf (Thfc) se ha asociado con enfermedades autoinmunes. Recientemente, se han descrito subpoblaciones de células Thfc que se caracterizan y clasifican según la expresión diferencial de los receptores de chemoquinas CXCR3 y CCR6 en células T CD4+CXCR5+ y que muestran diferencias funcionales en cuanto a su capacidad de ayudar a los linfocitos B. Un equilibrio alterado de estas subpoblaciones de Thfc se ha asociado con la patogenia de varias enfermedades autoinmunes, pero hasta donde sabemos estas subpoblaciones no han sido estudiadas en AR. Por lo tanto, nuestro primer objetivo fue examinar la frecuencia y el fenotipo de las células Th17 en sangre periférica de pacientes con AR de reciente comienzo (ARo), y en líquido sinovial de pacientes con AR establecida. Observamos una disminución significativa de la frecuencia de células Th17 y Th17/Th1 circulantes en pacientes ARo ACPA+, que asciende hasta los valores observados en los controles, tras el inicio del tratamiento con metotrexato. La frecuencia basal de células Th17 circulantes se correlacionó significativamente con el título de ACPA y con la presencia o ausencia de erosiones basales. Nuestro segundo objetivo era estudiar la frecuencia de las células Thfc, las subpoblaciones de Thfc y los plasmablastos circulantes, en pacientes con AR. Observamos que los pacientes con AR muestran una mayor frecuencia de células Thfc CD4+CXCR5+ICOS+ junto con una sobrerrepresentación de las subpoblaciones de células Thfc con fenotipo ayudador de linfocitos B. Por otro lado, sólo los pacientes con AR con enfermedad activa mostraban una mayor proporción de plasmablastos circulantes.Rheumatoid Arthritis (RA), a systemic autoimmune disease, is characterized by chronic joint inflammation, cartilage destruction and bone erosions. Numerous experimental data indicate that interleukin 17 (IL-17) plays an important role in the pathogenesis of RA. IL-17 deficient mice demonstrate a markedly attenuated form of collagen-induced arthritis and anti- IL-17 therapy in this mouse model of RA is associated with a significant reduction of severity. In human studies, high levels of IL-17 have been observed in the synovial fluid of patients with RA and IL-17 producing CD4+ T cells have been detected in RA synovial membranes. An altered percentage of Th17 cells has been described in the peripheral blood and synovial fluid of RA patients, but to date conflicting data have been reported. On the other hand, B cells also actively participate in RA pathogenesis through the production of autoantibodies. Follicular helper T cells (Tfh), promote B cell maturation and antibody production. Tfh cells play an important role in the pathogenesis of autoimmunity, and increased numbers have been described in murine models of inflammatory arthritis. Classical Tfh cells are located in secondary lymphoid organs. Several reports have subsequently described circulating populations of CD4+CXCR5+ T cells that display both phenotypic and functional features of true Tfh cells. Increased frequencies of circulating Tfh cell counterparts (cTfh) have been associated with autoimmune diseases. More recently, phenotypic and functionally distinct subpopulations of cTfh cells have been described, according to the differential expression of the chemoquine receptors CXCR3 and CCR6 on CD4+CXCR5+ T cells. An altered balance of these cTfh subsets is associated with the pathogenesis of autoimmunity but to our knowledge has not been investigated in RA. Therefore, our first objective was to examine the frequency and phenotype of Th17 cells in the peripheral blood of early RA (eRA) patients, and in the synovial fluid of patients with established RA. We have observed a significantly decreased frequency of circulating Th17 and Th17/Th1 cells in ACPA+ eRA patients that increase up to values observed in controls during follow-up after initiating treatment with methotrexate. The basal circulating Th17 frequency was significantly correlated with the titre of ACPA and with the presence or absence of basal erosions. Our second objective was to study the frequency of cTfh and cTfh cell subsets together with the frequency of circulating plasmablast in patients with RA. We observed that RA patients demonstrate an increased frequency of cTfh CD4+CXCR5+ICOS+ together with an overrepresentation of cTfh subsets bearing a phenotype associated with B cell helping capacity. In contrast, only RA patients with active disease show an increased proportion of circulating plasmablasts

Interaction of Eu-isotopes with saponite as a component of the engineered barrier

Bentonite is accepted as the best clay material in the engineered barrier of deep geological repositories (DGRs) for radioactive waste disposal. In recent years, the interactions between a wide range of rare-earth (REE) cations and smectites have been studied. A combined study of stable europium and radioactive isotopes is reported here. Saponite was subjected to hydrothermal reactions with stable and radioactive (152Eu) europium ions under subcritical conditions. The structural changes of saponite were evaluated by XRD and SEM. The effect of temperature and reaction time on the changes was quantified by measuring 152Eu through gamma spectrometry. The reaction between europium and saponite was a first-order reaction. The presence of Eu in the precipitate in an amount much higher than the cation exchange capacity of saponite confirmed participation of chemical reactions or surface adsorption in the europium immobilization, even at temperatures as low as 150°C. The reaction rate constant indicated that an 8- to 9-month period was needed for the completion, without significant changes, of the europium/saponite chemical reaction under the subcritical conditions of 200°C and 350°C.Medio Ambiente y Medio Rural y Marino 300/PC08/3-01.1Dirección General de Investigación Científica y Técnica CTQ2010-1487

Análisis Estadístico de Alumnos Becados en la Universidad Autónoma de Nayarit en el Periodo 2013-2014

Problema de InvestigaciónDeterminación de parámetros estadísticos en el otorgamiento de los diferentes tipos de becas a los alumnos de la Universidad Autónoma de Nayarit, tomando como referencia la información de la Unidad de Desarrollo Institucional que aparecen en la página oficial de la UAN. (Unidad de Desarrollo Institucional. Universidad Autónoma de Nayarit, n.d. y el Reglamento General de Becas de la UAN).ObjetivoAnalizar el comportamiento estadístico de las becas otorgadas a los alumnos de acuerdo a cada uno de los tipos de beca.Marco teóricoLa Secretará de Educación Pública a través de las Subsecretarías de Nivel superior y Medio Superior organiza el programa federal de becas a los estudiantes que de acuerdo a cada característica soliciten a los organismos destinados a esta función, tales como: la Coordinación Nacional de Becas de Educación Superior (2014) que establece doce tipos de becas para estudiantes de nivel superior y la CBSMES, Coordinación de Becas de Nivel Medio Superior, pone a disposición 8 tipos de becas para este nivel. Las UniversidadesPúblicas en el país a razón de la disponibilidad de los recursos etiquetados, en especial la Universidad Autónoma de Nayarit, para estos fines, programa año con año la emisión de la convocatoria a todos los planteles pertenecientes a la Universidad en el Estado de Nayarit,La Unidad de Desarrollo Institucional de la UAN concentra la información de los solicitantes y los beneficiarios de las becas, separándolas por tipo de beca otorgada.Lo anterior se sujeta al Reglamento General de Becas de Universidad Autónoma de Nayarit, que se convierte en documento rector que rige el procedimiento a seguir en este rubro

Uranium immobilization by FEBEX bentonite and steel barriers in hydrothermal conditions

FEBEX clay is considered a reference material in engineered barriers for safe storage of nuclear waste and uranium is a minor component of high-level radioactive waste (HLRW) and a main component of the spent nuclear fuel (SNF). Here, the kinetics of reaction of uranium with FEBEX was investigated in addition to the uranium immobilisation ability and the structural analysis of the reaction products. Hydrothermal treatments were accomplished with UO22+ and tetravalent actinide simulator ZrO2+, also present in HLRW. The quantification of the reaction was performed through gamma spectrometry of uranium. Two mechanisms for UO22+ retention by FEBEX were detected: adsorption and formation of stable and insoluble new phases. The structural analyses performed using ZrO2+, confirmed the uranium adsorption and the presence of new phases, ZrO2 and Zr(SiO4), that emphasise the existence of a chemical reaction with the bentonite. The analysis of the velocity of reaction uranium-clay minerals revealed temperature dependence. An exponential fitting suggested that the removal of uranium from solution at temperatures over 200 °C could be completed in less than a year. For lower temperatures, several years are needed. Milliequivalents of UO22+ immobilised by the clay depended on temperature and time and were over cation exchange capacity (CEC) of FEBEX even at 100 °C (reaching 600% of CEC). The reaction with steel, also temperature dependent, was finally analysed. At 200 °C 40–70% of uranium reacted with steel. But only 30–15% reacted at 300 °C and 100 °C. The reactions provide a stable immobilisation mechanism for uranium even when its sorption and swelling capacities fail. Our experiments will be of particular interest for very deep borehole disposals were higher temperatures and pressures are expected.ENRESA 0079000121FEDER Junta de Andalucía P12-FQM-56

Effect of a High-Intensity Circuit Training Program on the Physical Fitness of Wildland Firefighters

[EN] Wildland firefighting implies high physical and psychological demands for the personnel involved. Therefore, good physical fitness can help increase the work efficiency of wildland firefighters (WFFs) and safeguard their health. High-intensity circuit training (HICT) could be a good alternative to improve the physical condition of WFFs since it stands out for its functionality and economy. Therefore, the objective of this study was to analyze the effects of HICT on the WFFs’ physical fitness. The study involved 9 WFFs (8 males and 1 female; 29.8 ± 2.8 years; 175.6 ± 6.7 cm) who completed a training program and 9 WFF candidates (8 males and 1 female; 24.7 ± 6.6 yr, 176.5 ± 7.0 cm) as a control group. WFFs performed an 8-week HICT program (two weekly training sessions). The training sessions lasted approximately 45 min and were performed at an intensity >80% of maximal heart rate and RPE values >7.5. At the beginning and the end of the intervention, subjects’ physical fitness (i.e., aerobic capacity, cardiorespiratory endurance, muscular resistance and explosive strength) was assessed through different tests. After completing the training program, WFFs had significantly increased (p < 0.05) the speed at which the ventilatory thresholds were determined (12.4 ± 13.9 and 5.7 ± 7.3% for the ventilatory and respiratory compensation thresholds, respectively) and also their abdominal (31.2 ± 17.2%), lumbar (34.1 ± 13.5%) and upper limb (13.3 ± 16.0%) strength. Moreover, improvements (p < 0.05) in the explosive strength of legs (7.1 ± 5.8%) and performance in a specific physical employment test (12.2 ± 6.1%) were observed. In conclusion, the results of this study show that an 8-week high-intensity circuit training program could be an effective and safe method to improve WFFs’ physical fitness and performance.S

Laboratory assessment of heat strain in female and male wildland firefighters

[EN] Wildland firefighters (WFF) face a set of specific work-related factors that directly affect their physical and cognitive abilities and compromise their health and safety. The working conditions include hard physical work and environmental conditions that combine high temperatures and high radiant heat. Such environments make using personal protective equipment (PPE) mandatory to protect them from risks. This fact restricts heat removal and adds extra weight, increasing thermal strain and the risk of heat-related illnesses on WFF. Since the number of females WFF has increased, it is necessary to study the repercussions of heat stress on this group. To date, it is not yet well-known whether sex-related differences in thermoregulation will be relevant when the individuals are wearing PPE and performing high physical effort in a hot environment. Therefore, we aimed to investigate the physiological response when performing moderate to high-intensity effort in a hot-dry environment while wearing PPE according to sex. Twenty WFF 10 females [23.9 ± 3.2 yr, 163.8 ± 3.4 cm and 62.7 ± 9.1 kg] and 10 males [31.9 ± 6.6 yr, 178.8 ± 5.8 cm and 73.9 ± 7.7 kg]) performed a 125 min treadmill test in a controlled ambient (30 ºC and 30% relative humidity). The protocol consisted of two exercise stages where WFF performed different continuous and variable exercise bouts in order to mimic the effort performed during real deployments. Participants wore the full standard PPE during the test. Oxygen uptake (VO2), heart rate (HR), core temperature (CT) and chest temperature (SkT) were monitored throughout the test. HR and CT were used to calculate the physiological strain index (PSI). Differences in body mass pre-post trials corrected for fluid intake were used to calculate sweat production (SwP), sweating rate (SwR), and evaporative efficiency (EE). Differences (p < 0.05) between females and males were found in %VO2max (62.5 ± 7.4 vs 55.3 ± 5.), HR (155 ± 10 vs 134 ± 14 beats·min–1), % of maximal HR (81.3 ± 3.5 vs 42.3 ± 6.5), CT (38.0 ± 10 vs 37.7 ± 0.33 ºC), SkT (36.0 ± 0.6 vs 35.3 ± 0.6 ºC) and PSI (4.1 ± 0.5 vs 3.5 ± 0.6). Even though SwR was higher (p < 0.05) for male participants (1001.5 ± 268.3 ml) compared to females (647.5 ± 145.9 ml), females had higher EE (32.9 ± 4.6 vs 16.7 ± 6.2 %). In conclusion, performing high-intensity exercise in hot-dry conditions while wearing PPE leads to a higher thermal and cardiovascular load for female WFF, making them more susceptible to heat illness. These results could be linked to lower aerobic fitness, sweating rate, and hormonal aspects that increased the thermal burden

Visión del Estudiante hacia la Transformada de Laplace

Los investigadores de este trabajo muestran una visión por parte del estudiante del Área de Ciencias Básicas e Ingenierías (ACBI) de la Universidad Autónoma de Nayarit (UAN), respecto al aprendizaje de la transformada de Laplace, y en consecuencia la creación de una propuesta de estrategia didáctica para este tema. La propuesta está basada en el modelo de la escuadra invertida, cuyo objetivo es mejorar la didáctica por parte del profesor y mejorar el autoconocimiento por parte del alumno. Fue necesario de aplicar encuestas escala de Rensis Likert, aplicadas a alumnos de tercer semestre en adelante, y estas analizadas con el coeficiente de Cronbach, el cual arroja el nivel de confiabilidad del instrumento. Además, los resultados nos permiten partir para crear la propuesta didáctica

Influence of Personal Protective Equipment on Wildland Firefighters’ Physiological Response and Performance during the Pack Test

[EN] The Pack Test (PT) is a widely used test to establish readiness for work in wildland firefighting. It is common to perform this test dressed in regular exercise clothing. However, wildland firefighters (WFF) have to wear personal protective equipment (PPE) during their deployments, which increases the physiological strain and reduces their work capacity. This study aimed to analyse the impact of full PPE on PT performance. Nine male professional WFF performed in random order a PT walking at the fastest possible self-pace wearing two different clothing configurations: (i) traditional short sports gear (SG) and (ii) the PPE currently used by Spanish WFF. Heart rate (HR), rating of perceived exertion and lap time were recorded during the PT. In addition, oxygen uptake (VO2) was estimated through the individual VO2–HR relationship previously obtained during a graded exercise test. There was a significant decrease in the PT performance (i.e., completion time) (~12%, p < 0.05) in PPE. The physiological demands with this configuration were significantly higher (~10%, p < 0.05). WFF spent ~13 min above the anaerobic threshold in PPE vs. ~4 min in SG. A multiple stepwise regression analysis revealed that PT performance variation might be explained by the maximal aerobic velocity (84.5%) in PPE and the VO2max (75.9%) in SG. In conclusion, wearing complete PPE increases WFF’s physiological strain, which translates into a significant PT performance reduction. Performing the test walking at the fastest possible self-pace wearing the PPE would better reflect the high-intensity effort periods reported in real scenarios

Frequency of Th17 CD4+ T cells in early rheumatoid arthritis: A marker of anti-CCP seropositivity

Objective: To examine the frequency and phenotype of Th17 cells in the peripheral blood of early RA (eRA) patients. Methods: CD4+ T cells were isolated from the peripheral blood of 33 eRA patients, 20 established RA patients and 53 healthy controls (HC), and from the synovial fluid of 20 established RA patients (RASF), by ficoll-hypaque gradient and magnetical negative selection. After polyclonal stimulation, the frequency of Th17 and Th1 cells was determined by flow cytometry and concentrations of IL-17, IFN-γ, TNF-α and IL-10 were measured by ELISA in cell-free supernatants. Results: When all of our eRA patients were analyzed together, a significantly lower percentage of circulating Th17 cells and a lower CD4-derived IL-17 secretion were observed in comparison with HC. However, after stratifying by anti-CCP antibody status, circulating Th17 cells were decreased in anti-CCP(+) but not in anti-CCP(-)-eRA. All Th17 cells were CD45RO+CD45RA- and CCR6+. Dual Th17/Th1 cells were also exclusively decreased in anti-CCP(+)-eRA. Circulating Th17 and Th17/Th1 cells were negatively correlated with anti-CCP titres. When anti-CCP(+)-eRA patients were retested one year after initiating treatment with oral methotrexate, their circulating Th17 frequency was no longer different from HC. Of note, the percentage of circulating Th1 cells and the secretion of CD4-derived IFN-γ, TNF-α and IL-10 were not different between eRA patients and HC. In established RA patients, circulating Th17 and T17/Th1 cell frequencies were comparable to HC. In RASF, both Th17 and Th1 cells were increased when compared with blood of eRA patients, established RA patients and HC. Conclusion: Decreased circulating Th17 levels in eRA seem to be a marker of anti-CCP seropositivity, and return to levels observed in healthy controls after treatment with methotrexateThis work was supported by Ministerio de Ciencia e Innovación grant SAF 2009-07100, (http://www.idi.mineco.gob.es/portal/site/MICINN) and by RETICS Program, RD08/0075 (RIER) from ‘‘Instituto de Salud Carlos III’’ (ISCIII) (http://www.isciii.es/

3D Printed Porous Polyamide Macrocapsule Combined with Alginate Microcapsules for Safer Cell-Based Therapies

Cell microencapsulation is an attractive strategy for cell-based therapies that allows the implantation of genetically engineered cells and the continuous delivery of de novo produced therapeutic products. However, the establishment of a way to retrieve the implanted encapsulated cells in case the treatment needs to be halted or when cells need to be renewed is still a big challenge. The combination of micro and macroencapsulation approaches could provide the requirements to achieve a proper immunoisolation, while maintaining the cells localized into the body. We present the development and characterization of a porous implantable macrocapsule device for the loading of microencapsulated cells. The device was fabricated in polyamide by selective laser sintering (SLS), with controlled porosity defined by the design and the sintering conditions. Two types of microencapsulated cells were tested in order to evaluate the suitability of this device; erythropoietin (EPO) producing C2C12 myoblasts and Vascular Endothelial Growth Factor (VEGF) producing BHK fibroblasts. Results showed that, even if the metabolic activity of these cells decreased over time, the levels of therapeutic protein that were produced and, importantly, released to the media were stable.This work was done under the BIOPAN project (CIBER-BBN). Authors wish to thank the intellectual and technical assistance from the ICTS "NANBIOSIS", more specifically by the Drug Formulation Unit (U10) and the Micro-Nano Technology Unit (U8) of the CIBER in Bioengineering, Biomaterials & Nanomedicine (CIBERBBN). Also, they thank the support to research on cell microencapsulation from the University of the Basque Country UPV/EHU (EHUA 16/06) and the Basque Country Government (Grupos Consolidados, No ref: IT907-16). The authors acknowledge the financial support from the Ministerio de Economia y Competitividad (MINECO) (Spain) through Ramon y Cajal program (RYC-2013-14479). This work has made use of the Spanish ICTS Network MICRONANOFABS partially supported by MINECO