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Phytophthora cinnamomi is an important plant pathogen responsible for dieback diseases in plant genera including Quercus, Fagus, Castanea, Eucalyptus, and Pinus, among others, all over the world. P. cinnamomi infection exerts tremendous ecological and economic losses. Several strategies have been developed to combat this pathogenic oomycete, including the search for novel anti-oomycete compounds. In this work, a Mediterranean vascular plant, Phlomis purpurea, has been screened for secondary bioactivity against this pathogen. The genus Phlomis includes a group of herbaceous plants and shrubs described as producers of many different bioactive compounds, including several triterpenoids. Triterpenoids are well-known molecules synthesized by plants and microorganisms with potent antioxidant, antitumoral, and antimicrobial activities. We have isolated by HPLC-DAD and characterized by HPLC-MS and NMR two nortriterpenoid compounds (phlomispentaol A and phlomispurtetraolone) from the root extracts of P. purpurea. One of them (phlomispentaol A) is active against the plant pathogenic oomycete P. cinnamomi (based on in vitro inhibition bioassays). Based on their chemical structure and their relationship to other plant triterpenoids, oleanolic acid is proposed to be the common precursor for these molecules. The anti-oomycete activity shown by phlomispentaol A represents a promising alternative to counteract the worldwide-scale damage caused to forest ecosystems by this pathogen., Comunidad Autónoma de Extremadura, Principado de Asturias, Universidad de Oviedo, Depto. de Producción Animal, Fac. de Veterinaria, TRUE, pub

Bovine besnoitiosis is considered as a re-emergent disease in Europe. No treatments or vaccines are available for disease control. Therefore, the development of animal models of infection is urgently needed. The aim of the present study was to develop an experimental model of B. besnoiti infection in cattle. Two experimental infections were realized. In experiment A, 12 Holstein Friesian 3-month old male calves were inoculated intravenously with either 3 different doses of tachyzoites (G1: 108 ; G2: 107 ; G3: 106 ) or with PBS (G4). In experiment B, 6 young bulls (14 months of age) were inoculated with the infection dose that showed the best results in experiment A (106 tachyzoites). In both experiments, temperature and clinical signs compatible with acute and chronic besnoitiosis were monitored daily and blood samples were collected regularly for antibody and parasitemia detection. The experiment A was followed up to 70 days post-infection (pi), whilst the experiment B lasted 115 days pi. At the end of the trials, animals were euthanized and tissues from skin, eyes, respiratory and reproductive tracts among others, were collected for lesions and parasite detection. Clinical signs compatible with acute phase, such as lymphadenopathy and fever were observed in both calves (from 12 hours pi until 7 days pi) and young bulls (from 6 days pi until 9 days pi). Parasitemia was detected sporadically in calves from G1 on days 4 (n=2) and 7 dpi (n=3); and in G2 on 7 dpi (n=1). However, no clinical signs characteristic of the chronic stage of the disease, such as tissue cysts, were detected. All infected animals seroconverted around 16-19 days pi and antibody levels remained high until the end of the trials. In calves, parasite-DNA was detected in conjunctiva, ocular sclera, epididymis, as well as skin of scrotum and carpal zone (n=10, 6 of which belonged to calves inoculated with 106 tachyzoites). However, in young bulls only 2 tissues (pampiniform plexus and testicular paren

The European norm UNE 12326 for roofing slate defines the mechanical properties of a slate tile through the Bending Strength test, which defines the modulus of rupture (MoR) of the tile. This MoR is related to the durability of the slate, and is one of its main commercial quality properties. During the prospection task previous to open a new slate quarry, it is crucial to define the MoR. The Bending Strength test needs proper slate tiles and a flexion press. To supply these slate tiles it is frequently necessary to open experimental quarry fronts, which are very expensive, and do not guarantee the viability of the quarry. Therefore, a method which could reduce the costs and time for the mechanical characterization would be very useful. In this work we have tried to relate the MoR to the mineralogical and petrographic characteristics of slate, using the Petrographic Examination test, also part of UNE 12326. This test contemplates the finding of a numerical index called Mica Stacking Index (MSI) which quantifies the mica layers fabric. We collected fifteen samples of roofing slates from the Northwest of the Iberian Peninsula and we studied them by using the Bending Strength and Petrographic Examination tests, plus mineralogical quantification using X-ray diffraction and measure of the illite crystallinity (Kubler Index) to determine the metamorphic grade. We have found a strong positive correlation between MoR values and MSI, and a negative correlation between MoR and Mica percentages. These correlations may be used to deduce the MoR, reducing costs during the exploitation labours in roofing slate mining, and also can be used in the quality controls on a working slate quarry., Ministerio de Ciencia e Innovación, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

altitude, chronic mountain sickness, erythrocythemia, hypoxia

altitude, chronic mountain sickness, erythrocythemia, hypoxia

arterial oxygen saturation, chronic mountain sickness, heart rate, ventilation

arterial oxygen saturation, chronic mountain sickness, heart rate, ventilation

altitude, chronic mountain sickness, erythrocythemia, hypoxia

breath-holdning, circulation, hypoxia, oxyhemoglobin saturation, altitude

Epidemiological and experimental studies suggest that circulating erythrocytes play a role in the incidence of coronary heart disease. We investigated the influence of phenylhydrazine (PHZ)-induced anemia on the formation of atherosclerotic lesions in apo E-deficient mice on regular chow and on a high-fat, high-cholesterol diet during 10 weeks. The repeated doses of PHZ caused sustained anemia throughout the study, changes in the physical characteristics of erythrocytes and increased reticulocyte count. The lesions of the anemic animals were smaller than in the controls and this was even more evident in mice fed with the atherogenic diet. A positive correlation was found between circulating red blood cells at the end of the experiment and the area of aortic lesion. There was also a negative association between the lesion and the reticulocyte count. This reduced progression of atherosclerotic lesions is independent of nutritional status or the lipoprotein cholesterol distribution. The results suggest that mechanisms related to the number of circulating red blood cells may have a significant influence on the development of atherosclerosis.

Material hardness is a complex concept involving elastic and plastic deformation and cracking phenomena. It is at the microscopic level that the fundamental cutting mechanisms can be examined more accurately, because there are no macroscopic discontinuities at this level and because it is at this level that petrographic characteristics such as mineralogy, texture and voids exert their influence. Sawing rates were measured and the cut sections were then prepared as polished slides so that sawing rates could be directly correlated with observed petrographic characteristics. As each cut section had a different mineralogical composition, the influence of different characteristics could be evaluated. Indentation tests were used to obtain 137 Vickers hardness measurements for the different mineral phases quartz, microcline, plagioclase and biotite. The inverse relationship between hardness and sawing rate was demonstrated. The method is recommended in preference to using a single mineral with lower determination coefficient, such as quartz., Material hardness is a complex concept involving elastic and plastic deformation and cracking phenomena. It is at the microscopic level that the fundamental cutting mechanisms can be examined more accurately, because there are no macroscopic discontinuities at this level and because it is at this level that petrographic characteristics such as mineralogy, texture and voids exert their influence. Sawing rates were measured and the cut sections were then prepared as polished slides so that sawing rates could be directly correlated with observed petrographic characteristics. As each cut section had a different mineralogical composition, the influence of different characteristics could be evaluated. Indentation tests were used to obtain 137 Vickers hardness measurements for the different mineral phases quartz, microcline, plagioclase and biotite. The inverse relationship between hardness and sawing rate was demonstrated. The method is recommended in preference to using a single mineral with lower determination coefficient, such as quartz.