Utilización de la dendrogeomorfología como geoindicador para evaluar procesos de erosión

Use of dendrogeomorphology as geoindicator to assess erosion processes.Anatomical changes of exposed tree roots are a valuable tools to date erosion events. The roots of some tree species subjected to erosive events suffer changes allow to quantify such processes. A descriptive and quantitative study was conducted in Scots pine Pinus sylvestris L the Senda Schmidt, a popular trail located on the northern slope of the Sierra de Guadarrama (Central Iberian System, Spain). Measurement of significant parameters allowed the moment of exposure of the roots to be identified. These parameters were: a) width of the growth ring; b) number of cells per ring; c) percentage of latewood and d) diameter of cellular light in earlywood. A one-way analysis ANOVA was also carried out in order to establish statistically significant differences between homogeneous groups of measurements in preexposed and exposed roots

Response of Pinus sylvestris roots to sheet-erosion exposure: An anatomical approach

Anatomical changes of exposed tree roots are valuable tools to date erosion events, but the responses of diverse species under different types of erosion need still to be studied in detail. In this paper we analyze the histological changes that occur in roots of Scots pine (Pinus sylvestris L.) subjected to continuous denudation. A descriptive and quantitative study was conducted in the Senda Schmidt, a popular trail located on the northern slope of the Sierra de Guadarrama (Central Iberian System, Spain). Measurement of significant parameters allowed the moment of exposure of the roots to be identified. These parameters were: a) width of the growth ring; b) number of cells per ring; c) percentage of latewood and d) diameter of cellular light in earlywood. A one-way analysis ANOVA was also carried out in order to establish statistically significant differences between homogeneous groups of measurements in pre-exposed and exposed roots. Based on these analyses, Scots pine roots show a remarkable anatomical response to sheet-erosion exposure. Increased growth in the ring is accompanied by a slight reduction of the cell lumina of the earlywood tracheids. At the end of the ring, several rows of thick-walled tracheids define latewood tissue and visible annual borders very clearly. Furthermore, resin ducts often appear in tangential rows, increasing resin density in the tissue. All of these indicators made it possible to determine with precision the first year of exposure and to estimate precisely sheet erosion rates

Evidencias anatómicas de avenidas torrenciales en diferentes especies arbóreas

La caracterización de la respuesta anatómica de árboles afectados por avenidas torrenciales, resulta determinante a la hora de definir indicadores útiles para el estudio de la frecuencia y magnitud del proceso utilizando técnicas dendrogeomorfológicas. Con este propósito, se han analizado 96 muestras provenientes de diferentes especies arbóreas (Pinus pinaster Ait., Quercus pyrenaica Willd., Alnus glutinosa L, Fraxinus angustifolia Vahl. y Populus sp.), de la madera afectada por la carga sólida transportada durante el evento torrencial que tuvo lugar en 1997 en el arroyo Cabrera (Navaluenga, Sierra del Valle, Gredos Oriental). En campo, la toma de muestras consistió en obtener cuñas de madera con una sierra de mano y testigos cilíndricos con barrena Pressler, de aquellos árboles localizados en los bancos de orilla que presentaban descortezados por impacto. En laboratorio se prepararon, a partir de los tejidos vegetales, láminas delgadas obtenidas en sección transversal y con espesores comprendidos entre 10-15 μm. Posteriormente, se procedió a la adquisición de imágenes microscópicas (300 ppp, x 50 aumentos) para el análisis de los diversos parámetros anatómicos cuantitativos y cualitativos mediante el software WinCELL (Regent Instrument). Los resultados obtenidos muestran un cambio claro en los parámetros anatómicos analizados, como respuesta al daño producido por el evento torrencial de 1997. Dependiendo de cada especie, los principales indicadores tuvieron que ver con: el lumen celular de las traqueidas de la madera temprana así como el porcentaje y grosor de la pared celular (en pino); tamaño de los vasos (en aliso, fresno y roble) y dimensiones de las células de madera temprana acompañantes a vasos (aliso y álamo). Por último, también se observó la existencia de falsos anillos (alisos), depósitos gomosos (alisos, robles y fresnos) y presencia de tejidos desestructurados. Estos parámetros se presentan como indicadores útiles para la datación eventos pretéritos en esta zona de estudio y sectores análogos

Estimación de tasas de erosión hídrica a partir de Dendrogeomorfología

La senda Schmid es un camino bien conocido dentro de la Sierra de Guadarrama, caracterizándose por presentar un uso recreativo casi exclusivo, generalmente asociado al senderismo. Como resultado, se ha producido un proceso acelerado de erosión hídrica que ha derivado en la exposición de raíces de Pinus sylvestris L. Investigaciones previas llevadas a cabo en esta área, han utilizado técnicas dendrogeomorfológicas para estimar tasas de erosión hídrica basadas en el análisis del cambio del patrón morfológico de las series de anillos de crecimiento. Para ello, se calculó el cociente definido por la profundidad de rebajamiento existente entre la parte superior de la raíz hasta la superficie actual del suelo; y el número de anillos que denotan exposición subaérea, al definir éstos un patrón de crecimiento excéntrico. En este trabajo se han reevaluado, a partir de 18 muestras tomadas a lo largo de la senda, tasas de erosión hídrica sobre la base de la determinación del primer año de exposición mediante el análisis anatómico. Para ello, en laboratorio se obtuvieron imágenes de láminas delgadas de madera de raíz, las cuales fueron adquiridas por medio de un dispositivo digital acoplado a un microscopio óptico. Los parámetros considerados fueron: a) anchura del anillo de crecimiento; b) número de células por anillo; c) porcentaje de madera tardía; y d) diámetro de la luz celular en la madera temprana. Una vez finalizado el estudio anatómico, y con el fin de validar las conclusiones preliminares derivadas de éste, se realizó un análisis ANOVA, verificándose diferencias que han permitido utilizar la fecha de exposición para reevaluar las tasas con una mayor precisión que por medio del simple cambio de patrón excéntrico. Los resultados de tasas de erosión acelerada obtenidos y sus tendencias evolutivas en el tiempo podrían ayudar a la gestión adecuada y regulación del tránsito de excursionistas en áreas de especial fragilidad

Prognosis Impact of Diabetes in Elderly Women and Men with Non-ST Elevation Acute Coronary Syndrome

Ancià; Síndromes coronàries agudes; DonesAnciano; Síndromes coronarios agudos; MujeresElderly; Acute coronary syndromes; WomenFew studies have addressed to date the interaction between sex and diabetes mellitus (DM) in the prognosis of elderly patients with non-ST-segment elevation acute coronary syndrome (NSTEACS). Our aim was to address the role of DM in the prognosis of non-selected elderly patients with NSTEACS according to sex. A retrospective analysis from 11 Spanish NSTEACS registries was conducted, including patients aged ≥70 years. The primary end point was one-year all-cause mortality. A total of 7211 patients were included, 2,770 (38.4%) were women, and 39.9% had DM. Compared with the men, the women were older (79.95 ± 5.75 vs. 78.45 ± 5.43 years, p < 0.001) and more often had a history of hypertension (77% vs. 83.1%, p < 0.01). Anemia and chronic kidney disease were both more common in women. On the other hand, they less frequently had a prior history of arteriosclerotic cardiovascular disease or comorbidities such as peripheral artery disease and chronic pulmonary disease. Women showed a worse clinical profile on admission, though an invasive approach and in-hospital revascularization were both more often performed in men (p < 0.001). At a one-year follow-up, 1090 patients (15%) had died, without a difference between sexes. Male sex was an independent predictor of mortality (HR = 1.15, 95% CI 1.01 to 1.32, p = 0.035), and there was a significant interaction between sex and DM (p = 0.002). DM was strongly associated with mortality in women (HR: 1.45, 95% CI = 1.18–1.78; p < 0.001), but not in men (HR: 0.98, 95% CI = 0.84–1.14; p = 0.787). In conclusion, DM is associated with mortality in older women with NSTEACS, but not in men.This work was supported by grants from the Spanish Ministry of Economy and Competitiveness through the Carlos III Health Institute: CIBER-CV 16/11/00420, Madrid, Spain

Development and Validation of a Sensitive HPLC Assay for Determination of Sparfloxacin According to the European Medicines Agency Guideline

[EN] Sparfloxacin, a synthetic antibiotic belonging to the third-generation fluoroquinolones, has numerous pharmacokinetic and microbiological advantages which can make it an excellent candidate for the treatment of infections in sheep. The objective of this study was to develop and validate an analytical HPLC method to quantify sparfloxacin in sheep plasma, following the recommendations set out in the Guideline on Bioanalytical Method Validation of the European Union (EMEA/CHMP/EWP/192217/2009). The HPLC mobile phase consisted of acetonitrile and monopotassium phosphate buffer (1.36 g/L) 49:51 (v/v). Genabilic acid was used as internal standard. Mean retention times for sparfloxacin and genabilic acid were 2.6 and 5.8 min, respectively. The method met all specifications of the EMA guideline, being selective and linear in the range of 0.2–10 g/mL (R2 0.99). Within-run precision ranged between 0.00 and 0.88%, with an accuracy of 90.3–118.0% for the lower limit of quantitation (LLOQ). The LLOQ was 0.2 g/mL, and no interference from the biological matrix was found. The stability of sparfloxacin in the biological matrix was demonstrated under different storage conditions. Therefore, the method can be used to determine sparfloxacin concentrations in sheep plasma in different types of studies.S

Organocatalytic Enantioselective Vinylcyclopropane-Cyclopentene (VCP-CP) Rearrangement

We have demonstrated that the catalytic and enantioselective vinylcyclopropane-cyclopentene rearrangement can be carried out on (vinylcyclopropyl)acetaldehydes through activation via enamine intermediates. The reaction makes use of racemic starting materials that, upon ring opening facilitated by the catalytic generation of a donor-acceptor cyclopropane, deliver an acyclic iminium ion/dienolate intermediate in which all stereochemical information has been deleted. The final cyclization step forms the rearrangement product, showing that chirality transfer from the catalyst to the final compound is highly effective and leads to the stereocontrolled formation of a variety of structurally different cyclopentenes

Targeting γ-secretases protect against angiotensin II-induced cardiac hypertrophy

OBJECTIVE: The Notch pathway has been linked to pulmonary hypertension, but its role in systemic hypertension and, in particular in left ventricular hypertrophy (LVH), remains poorly understood. The main objective of this work was to analyse the effect of inhibiting the Notch pathway on the establishment and maintenance of angiotensin II (Ang-II)-induced arterial hypertension and LVH in adult mice with inducible genetic deletion of γ-secretase, and to test preclinically the therapeutic efficacy of γ-secretase inhibitors (GSIs). BASIC METHODS: We analysed Ang-II responses in primary cultures of vascular smooth muscle cells obtained from a novel mouse model with inducible genetic deletion of the γ-secretase complex, and the effects of GSI treatment on a mouse cardiac cell line. We also investigated Ang-II-induced hypertension and LVH in our novel mouse strain lacking the γ-secretase complex and in GSI-treated wild-type mice. Moreover, we analysed vascular tissue from hypertensive patients with and without LVH. MAIN RESULTS: Vascular smooth muscle cells activate the Notch pathway in response to Ang-II both 'in vitro' and 'in vivo'. Genetic deletion of γ-secretase in adult mice prevented Ang-II-induced hypertension and LVH without causing major adverse effects. Treatment with GSI reduced Ang-II-induced hypertrophy of a cardiac cell line 'in vitro' and LVH in wild-type mice challenged with Ang-II. We also report elevated expression of the Notch target HES5 in vascular tissue from hypertensive patients with LVH compared with those without LVH. CONCLUSION: The Notch pathway is activated in the vasculature of mice with hypertension and LVH, and its inhibition via inducible genetic γ-secretase deletion protects against both conditions. Preliminary observations in hypertensive patients with LVH support the translational potential of these findings. Moreover, GSI treatment protects wild-type mice from Ang-II-induced LVH without affecting blood pressure. Our results unveil the potential use of GSIs in the treatment of hypertensive patients with LVH.Juan de la Cierva postdoctoral contract from MINECO [JCI-2011-09663]; MINECO; ProCNIC Foundation; Spanish Ministry of Economy and Competitivity (MINECO) [SAF2013-46663-R]; Instituto de Salud Carlos III [RD12/0042/0028, RD12/0042/0009, MS-00151]; Inserm (jeune chercheur accueilli)S

Survival of spin state in magnetic porphyrins contacted by graphene nanoribbons

We report on the construction and magnetic characterization of a fully functional hybrid molecular system composed of a single magnetic porphyrin molecule bonded to graphene nanoribbons with atomically precise contacts. We use on-surface synthesis to direct the hybrid creation by combining two molecular precursors on a gold surface. High-resolution imaging with a scanning tunneling microscope finds that the porphyrin core fuses into the graphene nanoribbons through the formation of new carbon rings at chemically predefined positions. These ensure the stability of the hybrid and the extension of the conjugated character of the ribbon into the molecule. By means of inelastic tunneling spectroscopy, we prove the survival of the magnetic functionality of the contacted porphyrin. The molecular spin appears unaffected by the graphenoid electrodes, and we simply observe that the magnetic anisotropy appears modified depending on the precise structure of the contacts.We acknowledge the financial support from Spanish Agencia Estatal de Investigación (AEI) (project nos. MAT2016-78293-C6 and FIS2015-62538-ERC, and the Maria de Maeztu Units of Excellence Programme MDM-2016-0618), the Basque Government (Department Industry, grant no. PI-2015-1-42), the European project PAMS (610446), the Xunta de Galicia (Centro singular de investigación de Galicia accreditation 2016 to 2019, ED431G/09), the European Research Council (grant agreement no. 635919), and the European Regional Development FundS