Atlas y Libro Rojo de la Flora Vascular Amenazada de España. Manual de metodología del trabajo corológico y demográfico

El proyecto ''Atlas y Libro Rojo de la Flora Vascular Amenazada de España" (proyecto AFA) se ha desarrollado a iniciativa del Ministerio de Medio Ambiente, en el que han participado de forma coordinada más de 200 personas organizadas en una treintena de equipos de trabajo procedentes de universidades, centros de investigación y otras instituciones vinculadas a la conservación de plantas. Su objetivo principal es el inventariado basado en la cartografía, censo y catalogación de la flora vascular amenazada española. Este proyecto se encuentra enmarcado dentro en un extenso programa nacional de caracterización de la biodiversidad, denominado Inventario Nacional de Biodiversidad, que tiene como finalidad la creación y el mantenimiento a largo plazo de un inventario de la biodiversidad española, organizado en una serie de Atlas estructurados por grupos taxonómicos (http://www.mma.es/portal! secciones/biodiversidad / inventarios / inb/) . En el caso de la flora vascular, un total de 466 especies prioritarias, en su mayoría pertenecientes a las categorías "en peligro crítico" (CR) y "en peligro" (EN) se encuentran informatizadas en una base de datos del Ministerio de Medio Ambiente, I cuyos campos describen su corología en cuadrículas de 500 x 500 m, el tamaño de cada una de sus poblaciones, los factores de amenaza, el grado de protección territorial, las actuaciones emprendidas y las propuestas futuras de conservación. Una síntesis de dicha información fue publicada en 2003 (reeditada en 2004 y 2007) bajo el título ''Atlas y Libro Rojo de la Flora Vascular Amenazada de España" (Bañares el al., 2004). En un proceso continuo de ampliación se han sumado al proyecto otras series de 35 y 53 especies (mayoritariamente "vulnerables", VU), publicadas como adendas al Atlas y Libro Rojo en años sucesivos (Bañares el al., 2007, 2009). En el inicio de las labores organizativas del proyecto AFA, y con antelación a los trabajos de campo, se constituyó un grupo de trabajo con el objetivo de preparar un manual metodológico de obtención de datos aplicable a todos los taxones de flora vascular considerados y en todo el territorio. Este manual de metodología, que fue presentado a los equipos de trabajo en una reunión técnica celebrada en Miraflores de la Sierra (Madrid) en febrero de 2001 y que se publica con la presente edición, recopila las pautas dadas a los equipos de trabajo que participaron en la obtención de los datos de campo. Con la publicación de este Manual de Metodología aplicado en la ejecución del proyecto AFA se intenta lograr un doble objetivo: por un lado, divulgar la metodología empleada a un público más amplio al objeto de que pueda servir de base para la ejecución de otros estudios de la misma naturaleza en éste u otros entornos geográficos; en segundo lugar, dar máxima difusión a esta información para facilitar la posibilidad de que, en un futuro, cuando se emprendan acciones de naturaleza semejante sobre las plantas vasculares amenazadas de España, resulte posible comparar los resultados obtenidos en tal estudio con los publicados en el Atlas y Libro Rojo de la Flora Vascular Amenazada de España. La experiencia adquirida tras la aplicación de esta metodología a los más de 500 taxones estudiados durante estos años, más una serie de avances, fundamentalmente el acceso a ciertas herramientas como los Sistemas Globales de Navegación por Satélite (GNSS) (p.ej. GPS), los Sistemas de Información Geográfica (SIG), la fotografía digital y también el desarrollo de ciertas bases de datos fácilmente consultables, nos ha permitido ahora incluir un apartado adicional que recopila nuevas recomendaciones metodológicas a incorporar en futuros estudios de esta naturaleza.

El Sistema de Seguimiento de la Flora Vascular española. Perspectivas de futuro

. Año 2006. Proyecto Piloto de Diseño y Aplicación del Sistema de Seguimiento de la Biodiversidad Española . Año 2007. Ley 42/2007 del Patrimonio Natural y de la Biodiversidad. Titulo I, Capitulo I, Artículo 9. Objetivos y contenido del Inventario Español del Patrimonio Natural y de la Biodiversidad. Artículo 10. Sistema de Indicadores. Artículo 11. Informe sobre el estado del Patrimonio Natural y de la Biodiversidad. . Año 2008. Primera propuesta metodológica coordinada por Felipe Domínguez. . Año 2009. Taller en el IV Congreso de la SEBICOP de Almería . Año 2009. Reunión en Valencia . Finales del año 2009 y 2010. Finalización de la metodología y elaboración de la primera propuesta de trabajo de campo; coordinado por Felipe Martínez. . Año 2010. Estructura organizativa. Reunión en Madrid con Responsables Territoriales . Año 2010-2012*. Primera fase de trabajo de campo

Control de la Fusariosis vascular en clavel en el suroeste de España mediante la biodesinfección del suelo.

El presente trabajo presenta una evaluación de las alternativas no químicas al 1,3 dicloropropeno + cloropicrina (AGROC) usado para el control de la fusariosis vascular en clavel en campos experimentales del suroeste de España. Esta enfermedad ha sido un factor limitante en todas las regiones del mediterráneo para poder mantener el cultivo durante 2 años. Tiempo éste necesario para obtener un rendimiento económico aceptable. La desinfección del suelo está basada en el compostado de la materia orgánica, que combinada o no con la solarización, es agrupada bajo la denominación de biodesinfección. Los tratamientos evaluados fueron: compost de alperujo con o sin solarización (31días), compost de residuos post-cosecha de clavel y crisantemo con y sin solarización, compost de residuos post-cosecha de clavel y crisantemo + gallinaza con y sin solarización. La gravedad de la enfermedad y la producción de flores se evaluaron semanalmente durante los 2 años que duró el experimento. Los resultados mostraron que la biodesinfección del suelo utilizando compost de clavel y crisantemo + gallinaza + solarización confiere una aceptable protección contra la fusariosis vascular durante los 2 años que dura el cultivo. La producción fue significativamente mayor que en cualquier otro de los tratamientos. Los resultados además sugieren que la adición de la gallinaza y el uso del polietileno estándar de alta densidad (HDPE) de forma conjunta fueron el factor clave en el éxito de la desinfección. No hubo efecto de la solarización sola, posiblemente debido a la época en la cual se aplicó

Aportaciones a la flora vascular de Tielmes (Madrid).

Se dan a conocer 60 táxones de plantas vasculares presentes en el término municipal de Tielmes en el valle del Tajuña en el cuadrante suroriental de la provincia de Madrid. Algunas de ellas suponen citas relevantes dentro de la flora de Madrid, otras se destacan por su importancia corológica.

Noninvasive monitoring of serial changes in pulmonary vascular resistance and acute vasodilator testing using cardiac magnetic resonance

Objectives The study sought to evaluate the ability of cardiac magnetic resonance (CMR) to monitor acute and long-term changes in pulmonary vascular resistance (PVR) noninvasively. Background PVR monitoring during the follow-up of patients with pulmonary hypertension (PH) and the response to vasodilator testing require invasive right heart catheterization. Methods An experimental study in pigs was designed to evaluate the ability of CMR to monitor: 1) an acute increase in PVR generated by acute pulmonary embolization (n = 10); 2) serial changes in PVR in chronic PH (n = 22); and 3) changes in PVR during vasodilator testing in chronic PH (n = 10). CMR studies were performed with simultaneous hemodynamic assessment using a CMR-compatible Swan-Ganz catheter. Average flow velocity in the main pulmonary artery (PA) was quantified with phase contrast imaging. Pearson correlation and mixed model analysis were used to correlate changes in PVR with changes in CMR-quantified PA velocity. Additionally, PVR was estimated from CMR data (PA velocity and right ventricular ejection fraction) using a formula previously validated. Results Changes in PA velocity strongly and inversely correlated with acute increases in PVR induced by pulmonary embolization (r = –0.92), serial PVR fluctuations in chronic PH (r = –0.89), and acute reductions during vasodilator testing (r = –0.89, p ≤ 0.01 for all). CMR-estimated PVR showed adequate agreement with invasive PVR (mean bias –1.1 Wood units,; 95% confidence interval: –5.9 to 3.7) and changes in both indices correlated strongly (r = 0.86, p < 0.01). Conclusions CMR allows for noninvasive monitoring of acute and chronic changes in PVR in PH. This capability may be valuable in the evaluation and follow-up of patients with PH.

Species richness and similarity of vascular plants in the Spanish dehesas at two spatial scales

Aims of study: The goals of this paper are to summarize and to compare plant species richness and floristic similarity at two spatial scales; mesohabitat (normal, eutrophic, and oligotrophic dehesas) and dehesa habitat; and to establish guidelines for conserving species diversity in dehesas. Area of study: We considered four dehesa sites in the western Peninsular Spain, located along a climatic and biogeographic gradient from north to south. Main results: Average alpha richness for mesohabitats was 75.6 species, and average alpha richness for dehesa sites was 146.3. Gamma richness assessed for the overall dehesa habitat was 340.0 species. The species richness figures of normal dehesa mesohabitat were significantly lesser than of the eutrophic mesohabitat and lesser than the oligotrophic mesohabitat too. No significant differences were found for species richness among dehesa sites. We have found more dissimilarity at local scale (mesohabitat) than at regional scale (habitat). Finally, the results of the similarity assessment between dehesa sites reflected both climatic and biogeographic gradients. Research highlights: An effective conservation of dehesas must take into account local and regional conditions all along their distribution range for ensuring the conservation of the main vascular plant species assemblages as well as the associated fauna

Flora vascular del Tejedelo de Requejo (Zamora, España)

Flora vascular del Tejedelo de Requejo (Zamora, España)

Targeting Gβγ signaling in arterial vascular smooth muscle proliferation: A novel strategy to limit restenosis

Restenosis continues to be a major problem limiting the effectiveness of revascularization procedures. To date, the roles of heterotrimeric G proteins in the triggering of pathological vascular smooth muscle (VSM) cell proliferation have not been elucidated. βγ subunits of heterotrimeric G proteins (Gβγ) are known to activate mitogen-activated protein (MAP) kinases after stimulation of certain G protein-coupled receptors; however, their relevance in VSM mitogenesis in vitro or in vivo is not known. Using adenoviral-mediated transfer of a transgene encoding a peptide inhibitor of Gβγ signaling (βARKct), we evaluated the role of Gβγ in MAP kinase activation and proliferation in response to several mitogens, including serum, in cultured rat VSM cells. Our results include the striking finding that serum-induced proliferation of VSM cells in vitro is mediated largely via Gβγ. Furthermore, we studied the effects of in vivo adenoviral-mediated βARKct gene transfer on VSM intimal hyperplasia in a rat carotid artery restenosis model. Our in vivo results demonstrated that the presence of the βARKct in injured rat carotid arteries significantly reduced VSM intimal hyperplasia by 70%. Thus, Gβγ plays a critical role in physiological VSM proliferation, and targeted Gβγ inhibition represents a novel approach for the treatment of pathological conditions such as restenosis.

Evidence for a structural motif in toxins and interleukin-2 that may be responsible for binding to endothelial cells and initiating vascular leak syndrome

The dose-limiting toxicity of interleukin-2 (IL-2) and immunotoxin (IT) therapy in humans is vascular leak syndrome (VLS). VLS has a complex etiology involving damage to vascular endothelial cells (ECs), extravasation of fluids and proteins, interstitial edema, and organ failure. IL-2 and ITs prepared with the catalytic A chain of the plant toxin, ricin (RTA), and other toxins, damage human ECs in vitro and in vivo. Damage to ECs may initiate VLS; if this damage could be avoided without losing the efficacy of ITs or IL-2, larger doses could be administered. In this paper, we provide evidence that a three amino acid sequence motif, (x)D(y), in toxins and IL-2 damages ECs. Thus, when peptides from RTA or IL-2 containing this sequence motif are coupled to mouse IgG, they bind to and damage ECs both in vitro and, in the case of RTA, in vivo. In contrast, the same peptides with a deleted or mutated sequence do not. Furthermore, the peptide from RTA attached to mouse IgG can block the binding of intact RTA to ECs in vitro and vice versa. In addition, RTA, a fragment of Pseudomonas exotoxin A (PE38-lys), and fibronectin also block the binding of the mouse IgG-RTA peptide to ECs, suggesting that an (x)D(y) motif is exposed on all three molecules. Our results suggest that deletions or mutations in this sequence or the use of nondamaging blocking peptides may increase the therapeutic index of both IL-2, as well as ITs prepared with a variety of plant or bacterial toxins.

An antagonistic vascular endothelial growth factor (VEGF) variant inhibits VEGF-stimulated receptor autophosphorylation and proliferation of human endothelial cells

Vascular endothelial growth factor (VEGF) is a potent mitogen with a unique specificity for endothelial cells and a key mediator of aberrant endothelial cell proliferation and vascular permeability in a variety of human pathological situations, such as tumor angiogenesis, diabetic retinopathy, rheumatoid arthritis, or psoriasis. VEGF is a symmetric homodimeric molecule with two receptor binding interfaces lying on each pole of the molecule. Herein we report on the construction and recombinant expression of an asymmetric heterodimeric VEGF variant with an intact receptor binding interface at one pole and a mutant receptor binding interface at the second pole of the dimer. This VEGF variant binds to VEGF receptors but fails to induce receptor activation. In competition experiments, the heterodimeric VEGF variant antagonizes VEGF-stimulated receptor autophosphorylation and proliferation of endothelial cells. A 15-fold excess of the heterodimer was sufficient to inhibit VEGF-stimulated endothelial cell proliferation by 50%, and a 100-fold excess resulted in an almost complete inhibition. By using a rational approach that is based on the structure of VEGF, we have shown the feasibility to construct a VEGF variant that acts as an VEGF antagonist.

Patterns of brain angiogenesis after vascular endothelial growth factor administration in vitro and in vivo

Vascular endothelial growth factor (VEGF) is a secreted endothelial cell mitogen that has been shown to induce vasculogenesis and angiogenesis in many organ systems and tumors. Considering the importance of VEGF to embryonic vascularization and survival, the effects of administered VEGF on developing or adult cerebrovasculature are unknown: can VEGF alter brain angiogenesis or mature cerebrovascular patterns? To examine these questions we exposed fetal, newborn, and adult rat cortical slice explants to graduated doses of recombinant VEGF. The effects of another known angiogenic factor, basic fibroblast growth factor (bFGF), were evaluated in a comparable manner. In addition, we infused VEGF via minipump into the adult cortex. Significant angiogenic effects were found in all VEGF experiments in a dose-responsive manner that were abolished by the addition of VEGF neutralizing antibody. Fetal and newborn explants had a highly complex network of branched vessels that immunoexpressed the flt-1 VEGF receptor, and flk-1 VEGF receptor expression was determined by reverse transcription–PCR. Adult explants had enlarged, dilated vessels that appeared to be an expansion of the existing network. All bFGF-treated explants had substantially fewer vascular profiles. VEGF infusions produced both a remarkable localized neovascularization and, unexpectedly, the expression of flt-1 on reactive astrocytes but not on endothelial cells. The preponderance of neovascularization in vitro and in vivo, however, lacked the blood–brain barrier (BBB) phenotype marker, GLUT-1, suggesting that in brain the angiogenic role of VEGF may differ from a potential BBB functional role, i.e., transport and permeability. VEGF may serve an important capacity in neovascularization or BBB alterations after brain injury.

Fibrinogen deficiency reduces vascular accumulation of apolipoprotein(a) and development of atherosclerosis in apolipoprotein(a) transgenic mice

To test directly whether fibrin(ogen) is a key binding site for apolipoprotein(a) [apo(a)] in vessel walls, apo(a) transgenic mice and fibrinogen knockout mice were crossed to generate fibrin(ogen)-deficient apo(a) transgenic mice and control mice. In the vessel wall of apo(a) transgenic mice, fibrin(ogen) deposition was found to be essentially colocalized with focal apo(a) deposition and fatty-streak type atherosclerotic lesions. Fibrinogen deficiency in apo(a) transgenic mice decreased the average accumulation of apo(a) in vessel walls by 78% and the average lesion (fatty streak type) development by 81%. Fibrinogen deficiency in wild-type mice did not significantly reduce lesion development. Our results suggest that fibrin(ogen) provides one of the major sites to which apo(a) binds to the vessel wall and participates in the generation of atherosclerosis.

20-Hydroxyeicosatetraenoic acid mediates calcium/calmodulin-dependent protein kinase II-induced mitogen-activated protein kinase activation in vascular smooth muscle cells

Norepinephrine (NE) and angiotensin II (Ang II), by promoting extracellular Ca2+ influx, increase Ca2+/calmodulin-dependent kinase II (CaMKII) activity, leading to activation of mitogen-activated protein kinase (MAPK) and cytosolic phospholipase A2 (cPLA2), resulting in release of arachidonic acid (AA) for prostacyclin synthesis in rabbit vascular smooth muscle cells. However, the mechanism by which CaMKII activates MAPK is unclear. The present study was conducted to determine the contribution of AA and its metabolites as possible mediators of CaMKII-induced MAPK activation by NE, Ang II, and epidermal growth factor (EGF) in vascular smooth muscle cells. NE-, Ang II-, and EGF-stimulated MAPK and cPLA2 were reduced by inhibitors of cytochrome P450 (CYP450) and lipoxygenase but not by cyclooxygenase. NE-, Ang II-, and EGF-induced increases in Ras activity, measured by its translocation to plasma membrane, were abolished by CYP450, lipoxygenase, and farnesyltransferase inhibitors. An AA metabolite of CYP450, 20-hydroxyeicosatetraenoic acid (20-HETE), increased the activities of MAPK and cPLA2 and caused translocation of Ras. These data suggest that activation of MAPK by NE, Ang II, and EGF is mediated by a signaling mechanism involving 20-HETE, which is generated by stimulation of cPLA2 by CaMKII. Activation of Ras/MAPK by 20-HETE amplifies cPLA2 activity and releases additional AA by a positive feedback mechanism. This mechanism of Ras/MAPK activation by 20-HETE may play a central role in the regulation of other cellular signaling molecules involved in cell proliferation and growth.

Conditional switching of vascular endothelial growth factor (VEGF) expression in tumors: Induction of endothelial cell shedding and regression of hemangioblastoma-like vessels by VEGF withdrawal

We have recently shown that VEGF functions as a survival factor for newly formed vessels during developmental neovascularization, but is not required for maintenance of mature vessels. Reasoning that expanding tumors contain a significant fraction of newly formed and remodeling vessels, we examined whether abrupt withdrawal of VEGF will result in regression of preformed tumor vessels. Using a tetracycline-regulated VEGF expression system in xenografted C6 glioma cells, we showed that shutting off VEGF production leads to detachment of endothelial cells from the walls of preformed vessels and their subsequent death by apoptosis. Vascular collapse then leads to hemorrhages and extensive tumor necrosis. These results suggest that enforced withdrawal of vascular survival factors can be applied to target preformed tumor vasculature in established tumors. The system was also used to examine phenotypes resulting from over-expression of VEGF. When expression of the transfected VEGF cDNA was continuously “on,” tumors became hyper-vascularized with abnormally large vessels, presumably arising from excessive fusions. Tumors were significantly less necrotic, suggesting that necrosis in these tumors is the result of insufficient angiogenesis.

Immunotargeting of liposomes to activated vascular endothelial cells: A strategy for site-selective delivery in the cardiovascular system

Endothelial-selective delivery of therapeutic agents, such as drugs or genes, would provide a useful tool for modifying vascular function in various disease states. A potential molecular target for such delivery is E-selectin, an endothelial-specific cell surface molecule expressed at sites of activation in vivo and inducible in cultured human umbilical vein endothelial cells (HUVEC) by treatment with cytokines such as recombinant human interleukin 1β (IL-1β). Liposomes of various types (classical, sterically stabilized, cationic, pH-sensitive), each conjugated with mAb H18/7, a murine monoclonal antibody that recognizes the extracellular domain of E-selectin, bound selectively and specifically to IL-1β-activated HUVEC at levels up to 275-fold higher than to unactivated HUVEC. E-selectin-targeted immunoliposomes appeared in acidic, perinuclear vesicles 2–4 hr after binding to the cell surface, consistent with internalization via the endosome/lysosome pathway. Activated HUVEC incubated with E-selectin-targeted immunoliposomes, loaded with the cytotoxic agent doxorubicin, exhibited significantly decreased cell survival, whereas unactivated HUVEC were unaffected by such treatment. These results demonstrate the feasibility of exploiting cell surface activation markers for the endothelial-selective delivery of biologically active agents via immunoliposomes. Application of this targeting approach in vivo may lead to novel therapeutic strategies in the treatment of cardiovascular disease.