583 research outputs found

    The essential oil of Thymbra capitata and its application as a biocide on stone and derived surfaces

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    Many chemicals used nowadays for the preservation of cultural heritage pose a risk to both human health and the environment. Thus, it is desirable to find new and eco-friendly biocides that can replace the synthetic ones. In this regard, plant essential oils represent effective alternatives to synthetic substances for the preservation of historical monuments. Thymbra capitata (syn. Thymus capitatus) is a medicinal and aromatic plant growing in the Mediterranean area and endowed with important pharmacological properties related to its essential oil. Among them, the antimicrobial ones make the T. capitata essential oil an ideal candidate for industrial applications; for instance, as biocide for the inhibition and elimination of biological patinas of cyanobacteria and green algae on historical monuments. In the present work, we studied the chemical composition of the essential oil from T. capitata growing in Malta by gas chromatography-mass spectrometry (GC/MS). The major volatile component is the phenolic monoterpene carvacrol (73.2%), which is capable of damaging the cytoplasmic membrane and to interfere both in the growth curve and in the invasive capacity, though the contribution of minor components γ-terpinene and p-cymene cannot be disregarded. For the oil application on the stone surface, Pickering emulsions systems were prepared with an essential oil/water 1:3 mass ratio stabilized with kaolinite at 4 mass% in the presence of Laponite®; this allowed to limit the fast volatility of the oil and guaranteed a better application and an easier removal from the artefacts attacked by biodeteriogens both indoor and outdoor. This formulation caused the elimination of biodeteriogens from treated surfaces without residuals or films on artworks surface, and the effect was retained up to four months

    Utility of ElastPQ point-shear wave elastography in the work-up of patients with primary sclerosing cholangitis

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    Background & Aims: Liver stiffness measurement (LSM) and spleen stiffness measurement (SSM) have been shown to be useful tools for assessing the risk of fibrosis and portal hypertension, respectively. However, data on the accuracy of LSM and SSM measured by point-shear wave elastography (pSWE) in patients affected by primary sclerosing cholangitis (PSC) are still lacking. Thus, we aimed to prospectively assess their performance in a cohort of patients with PSC. Methods: We determined the correlation between LSM assessed by a pSWE technique (ElastPQ) and by FibroScan-transient elastography (F-TE). Furthermore, we used receiver-operating characteristic curves and area under the curves (AUROC) to evaluate the performance of LSM by ElastPQ for the staging of fibrosis, using F-TE as a reference standard, and the performance of LSM and SSM by ElastPQ in predicting the presence of oesophageal varices (OVs). Results: One hundred and fifty-two patients with PSC (93 males [61.2%], mean age 46 ± 16 years) were prospectively recruited. ElastPQ and F-TE LSMs were available for all patients, while ElastPQ SSM was available in 109 (72%) patients of whom 35 underwent upper gastrointestinal endoscopy within 1 year of the ultrasound assessment. ElastPQ LSM showed an excellent correlation with F-TE (p <0.001, Spearman's 0.93; Lin's 0.86) and a good diagnostic accuracy for fibrosis staging along all stages of liver fibrosis (AUROCs 0.96, 0.97, 0.97 and 0.99 for fibrosis stages F≥1, F≥2, F≥3 and F=4, respectively), using F-TE as a surrogate of histological fibrosis. ElastPQ SSM showed a good diagnostic performance in predicting the presence of OVs at endoscopy. Conclusions: LSM and SSM by ElastPQ can be used as accurate tools for liver fibrosis risk assessment and fibrosis staging, as well as for predicting the presence of OVs in the work-up of patients with PSC. Impact and implications: Liver and spleen stiffness measurement (LSM and SSM, respectively) by ElastPQ point-shear wave elastography in patients with primary sclerosing cholangitis represent reliable and reproducible tools for non-invasively staging the severity of liver disease and stratifying patients according to their risk of developing liver-related outcomes. In particular, LSM shows good accuracy for staging liver fibrosis and therefore detecting those patients at high risk of having compensated advanced chronic liver disease who require close monitoring. SSM seems to be promising to detect the risk of portal hypertension and therefore of oesophageal varices, enabling the triaging of patients who really need to undergo a screening endoscopy

    Changes over 26 Years in the Avifauna of the Bogotá Region, Colombia: Has Climate Change Become Important?

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    High Neotropical mountains are among the most threatened ecosystems by climate change and this problem could be accentuated in cities where temperatures are higher. However, there are few data of long-term avifaunal changes in Neotropical cities, and the potential impact of climate change has yet to be addressed. Using data from 26 years of Audubon's Christmas Bird Counts (CBCs) in the Bogotá area (ca. 2,600–3,100 m in Colombia's eastern Andes), we analyze long-term changes of the avifauna using linear regressions corrected for species' habitat preferences and compared urban and rural sites. For the CBC we followed the National Audubon Society's methodology in which birds are counted over a 24-h period within a fixed circle 24 km in diameter. We recorded 235 species in the Bogotá circle with an average of 122 spp/year, including 46 boreal migrants, three endemic species, and four endemic subspecies, two globally and four locally threatened species. Species richness was higher in rural than in urban areas and most species were associated with native forest and scrub and wetlands. Among the species that were analyzed for changes in time 31% increased, 20% decreased, and 49% did not change. Strong fluctuations or changes in abundance were more frequent in urban than rural environments. Many of the species that increased or became established during the CBC interval came from lower elevations or the warmer, drier parts of the region beyond the count circle. By contrast, the lower elevational limits moved to higher elevations in several species that decreased. Climate change with its related effects represented the factor associated with the most changes in abundance. Other potential causes were direct human actions, mostly associated with urbanization, and “natural” successional changes in vegetation; predation by feral dogs and cowbird parasitism also affected several species negatively. Observations indicate that these factors will continue into the future, and the effects of climate change and urbanization in particular will probably intensify. The Bogotá CBC has provided much valuable information for Neotropical urban ornithology and its practice should be encouraged in other Latin American cities and should definitely continue in Bogotá for many years to come

    Cytotoxic Activity and Composition of Petroleum Ether Extract from Magydaris tomentosa (Desf.) W. D. J. Koch (Apiaceae).

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    The petroleum ether extract of Magydaris tomentosa flowers (Desf.) W. D. J. Koch has been analyzed by GC-MS. It is mainly constituted by furanocoumarins such as xanthotoxin, xanthotoxol, isopimpinellin, and bergaptene. Other coumarins such as 7-methoxy-8-(2-formyl-2-methylpropyl) coumarin and osthole also occurred. The antiproliferative activity of Magydaris tomentosa flower extract has been evaluated in vitro on murine monocyte/macrophages (J774A.1), human melanoma (A375) and human breast cancer (MCF-7) tumor cell lines, showing a major activity against the latter

    Headspace Volatile Composition of the Flowers of Caralluma europaea N.E.Br. (Apocynaceae)

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    The volatile constituents of the flowers of Caralluma (Apteranthes) europaea (Guss.) N.E. Br. (Apocynaceae - Asclepiadoideae) from Lampedusa Island were analyzed by headspace method. The analyses allowed the identification and quantification of 41 compounds. The main components were, among the monoterpenoids, terpinolene (23.3%), a-terpinene (19.1%) and linalool (18.4%), whereas, among the carbonylic compounds the major constituents were heptanal (2.0%), octanoic acid (2.4%) and hexanoic acid (1.7%). It is worth to mention the presence of a nitrogen containing compound, indole (0.8%) and of a sulphur containing compound, dimethylsulphide (t). The compounds found in the flowers of C. europea have been compared with data available in the literature as regard to their odor, presence in other sapromyiophilous taxa, possible role as semiochemicals, and presence in decaying organ matter. 89.3% of total constituents have been described in other sapromyiophilous taxa. Some of the compounds are present in several type of decaying organic matter (excrements, body in decomposition, and spoiled fish, etc). Several volatiles found in C. europea flowers are used as semiochemicals in Hymenoptera, Coleoptera, Diptera, Lepidoptera and other insects. Sixteen volatiles, accounting for 32.4% of the total constituents, are described as attractants of some Diptera families with a biology linked to decaying organic matters. Our data thus confirm that C. europea floral bouquet falls within the sapromyiophilous pollination syndrome

    Cost-effectiveness of biological therapy compared with methotrexate in the treatment for rheumatoid arthritis in Colombia

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    Artículo original2993-2997The objectives of the study are to develop a cost-effectiveness model comparing biological therapy (BT) with methotrexate (MTX) alone, in the treatment for rheumatoid arthritis (RA), combining clinical and quality-of-life data from international trials with local costs and local epidemiological data. We designed a six-month cycle Markov model with five functional states, based on Health Assessment Questionnaire, with patients initiating treatment in any of the predefined states, based on a sample of 150 local RA patients. Simulations ran for 10 and 20 years, and for the whole life span. Utilities, in quality-adjusted life years (QALY), were taken from international literature. Discount rate was 3 % for costs and utilities. We calculated direct and indirect costs using a combination of international and local data. Results are presented as incremental cost-effectiveness ratios (ICER). ICERs in euros per QALY were 143,072 for 10 years; 139,332 for 20 years; and 137,712 for the whole life span. Total costs with MTX were lower than with BT, despite higher out of pocket, productivity, and complication costs. Under conventional thresholds, and for the "average" RA patient, BT would not be cost-effective in Colombia. BT compared to MTX provides more QALYs, but at a high cost. When ICERs were estimated for Colombia, BT would not be cost-effective. We propose different thresholds for different conditions, perhaps prioritizing chronic diseases that lead to disability

    Lista de chequeo de las aves de Colombia: Una síntesis del estado del conocimiento desde Hilty & Brown

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    The taxonomy and knowledge of the distribution of Colombian avifauna has undergone great changes since the publication of “A Guide to the Birds of Colombia” by Hilty & Brown (1986) to the extent that we are unaware of how many and which species inhabit the Colombian territory. Here, we present a checklist of the birds of Colombia updated to August 2017 with a review of 340 references dealing with the distribution of Colombian birds. In sum, we report 1909 species for continental and insular Colombia, 216 of which have been added mainly since 1986. Although there are new data on distribution from 66% of the Colombian avifauna, most publications (87%) and new records (53%) are concentrated to the west of the Eastern cordillera (trans-Andean region). Based on the data we identify those regions of the country with knowledge gaps, which deserve more interest from researchers. Moreover, we encourage the ornithological community to publish their unpublished data and to improve the evidence supporting future new records for the country.La taxonomía y conocimiento de la distribución de la avifauna colombiana ha sufrido grandes cambios desde la publicación de “A Guide to the Birds of Colombia” por Hilty & Brown (1986), a tal punto que hoy no se sabe con precisión cuántas y cuáles especies de aves existen en el territorio colombiano. Presentamos la lista de chequeo de la avifauna de Colombia a agosto de 2017 con base en la revisión de 340 referencias relacionadas con la distribución de la avifauna colombiana. En total, reportamos 1909 especies de aves para el territorio continental e insular del país, de las cuales 216 han sido adicionadas principalmente a partir de 1986. Aunque existe información novedosa sobre distribución para cerca del 66% de la avifauna colombiana, la mayoría de las publicaciones (87%) y registros (53%) se concentran al occidente de la cordillera Oriental (región transandina). Con base en esta información identificamos aquellas áreas del país con vacíos de conocimiento que ameritan mayor interés por parte de los investigadores. Además, estimulamos a la comunidad ornitológica a publicar la información inédita represada, al igual que mejorar la evidencia que soporta los registros novedosos para el país
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