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1.
Arch Bronconeumol ; 2019 Nov 25.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31780284

RESUMO

INTRODUCTION: MicroRNA-7 (miR-7) has a suppressive role in lung cancer and alterations in its DNA methylation may contribute to tumorigenesis. As COPD patients with emphysema have a higher risk of lung cancer than other COPD phenotypes, we compared the miR-7 methylation status among smoker subjects and patients with various COPD phenotypes to identify its main determinants. METHODS: 30 smoker subjects without airflow limitation and 136 COPD patients without evidence of cancer were recruited in a prospective study. Clinical and functional characteristics were assessed and patients were classified into: frequent exacerbator, emphysema, chronic bronchitis and asthma COPD overlap (ACO). DNA collected from buccal epithelial samples was isolated and bisulfite modified. miR-7 methylation status was evaluated by quantitative methylation-specific polymerase chain reaction (qMSP). RESULTS: miR-7 Methylated levels were higher in COPD patients than in smokers without airflow limitation (23.7±12.4 vs. 18.5±8.8%, p=0.018). Among COPD patients, those with emphysema had higher values of methylated miR-7 (27.1±10.2%) than those with exacerbator (19.4±9.9%, p=0.004), chronic bronchitis (17.3±9.0%, p=0.002) or ACO phenotypes (16.0±7.2%, p=0.010). After adjusting for clinical parameters, differences between emphysematous patients and those with other phenotypes were retained. In COPD patients, advanced age, mild-moderate airflow limitation, reduced diffusing capacity and increased functional residual capacity were identified as independent predictors of methylated miR-7 levels. CONCLUSION: The increase of miR-7 methylation levels experienced by COPD patients occurs mainly at the expense of the emphysema phenotype, which might contribute to explain the higher incidence of lung cancer in these patients.

2.
Cell Biosci ; 9: 63, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31406565

RESUMO

Non-small-cell lung cancer (NSCLC) is the most common malignancy worldwide. Platinum-based chemotherapy is the standard of care for these patients. Recent research showed that miR-7 methylation status is a biomarker of cisplatin resistance in lung and ovarian cancer cells, which is one of the major limitations associated with their clinical management. The aim of the present study is to provide clinical insights associated with this novel potential biomarker in NSCLC patients by comparing the miR-7 methylation status with the cisplatin treatment response. Our results analyzed in 81 samples show that miR-7 methylation is a common event in tumor tissue and it is more frequent as the stage of the disease advances, remaining in 75% of metastatic patients. Tumor miR-7 unmethylation trend to a better PFS in early stages, and when our data was validated in an extended "in silico" cohort of 969 patients we obtained a significant increment in PFS and OS in those patients harboring miR-7 unmethylated (p = 0.010 and p = 0.007 respectively). When we select those early-stages patients harbouring miR-7 methylation, we observed that adenocarcinoma patients present a dramatic decrease in PFS compared with squamous cell carcinoma patients (median 18.9 versus 59.7 months, p = 0.002). In conclusion, our results show that presence of miR-7 methylation in early-stage NSCLC is suggestive of aggressive behavior, especially for adenocarcinoma patients. One major challenge in early diagnosis in NSCLC is identify the subgroup of patients that could benefit for adjuvant therapy, our data establish the basis for epigenetic classification on early-stage NSCLC that could influence treatment decisions in the future.

3.
Arthritis Rheumatol ; 71(10): 1616-1625, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31087542

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of increasing the dose interval of subcutaneous tocilizumab (TCZ-SC) in patients with rheumatoid arthritis (RA) who are in clinical remission. METHODS: RA patients with active disease and an inadequate response to conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) or to a biologic agent were entered into a single-arm treatment phase with 162 mg of TCZ-SC administered once weekly (TCZ-SC 162 mg qw) as monotherapy or in combination with a csDMARD for 24 weeks. Patients who achieved clinical remission at weeks 20 and 24 were randomized to continue with the same regimen or to switch to 162 mg TCZ-SC administered every 2 weeks (TCZ-SC 162 mg q2w) for 24 weeks (open-label). Patients with a Disease Activity Score in 28 joints (DAS28) of <2.6 were considered to be in clinical remission. RESULTS: In total, 179 (45%) of 401 patients in the single-arm phase achieved clinical remission and were randomized to continue to receive TCZ-SC 162 mg qw (n = 89) or to switch to TCZ-SC 162 mg q2w (n = 90) for 24 weeks. At week 48, significantly more patients treated with TCZ-SC 162 mg qw remained in clinical remission compared to patients who received TCZ-SC 162 mg q2w (90% versus 73%; P = 0.004). The results of other efficacy measures revealed greater efficacy with TCZ-SC 162 mg qw, but none of the efficacy outcomes in this group were significantly different from those in patients treated with TCZ-SC 162 mg q2w, except for the mean change from baseline in the DAS28 score at week 48 (mean change -4.07 points [SD 1.29] versus -3.65 points [SD 1.35]; P = 0.034). Tolerability and safety parameters were similar between the treatment groups. CONCLUSION: Increasing the dose interval of TCZ-SC in patients with RA was associated with a lower likelihood of maintaining remission after 24 weeks and was not associated with better tolerability. However, most patients were able to sustain remission with a half-dose of TCZ-SC, and therefore this strategy deserves further investigation.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Antirreumáticos/administração & dosagem , Artrite Reumatoide/tratamento farmacológico , Adulto , Idoso , Esquema de Medicação , Feminino , Humanos , Injeções Subcutâneas , Quimioterapia de Manutenção/métodos , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Resultado do Tratamento
4.
Environ Pollut ; 243(Pt A): 427-436, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30212797

RESUMO

In Mediterranean areas, dry deposition is a major component of the total atmospheric N input to natural habitats, particularly to forest ecosystems. An innovative approach, combining the empirical inferential method (EIM) for surface deposition of NO3- and NH4+ with stomatal uptake of NH3, HNO3 and NO2 derived from the DO3SE (Deposition of Ozone and Stomatal Exchange) model, was used to estimate total dry deposition of inorganic N air pollutants in four holm oak forests under Mediterranean conditions in Spain. The estimated total deposition varied among the sites and matched the geographical patterns previously found in model estimates: higher deposition was determined at the northern site (28.9 kg N ha-1 year-1) and at the northeastern sites (17.8 and 12.5 kg N ha-1 year-1) than at the central-Spain site (9.4 kg N ha-1 year-1). On average, the estimated dry deposition of atmospheric N represented 77% ±â€¯2% of the total deposition of N, of which surface deposition of gaseous and particulate atmospheric N averaged 10.0 ±â€¯2.9 kg N ha-1 year-1 for the four sites (58% of the total deposition), and stomatal deposition of N gases averaged 3.3 ±â€¯0.8 kg N ha-1 year-1 (19% of the total deposition). Deposition of atmospheric inorganic N was dominated by the surface deposition of oxidized N in all the forests (means of 54% and 42% of the dry and total deposition, respectively). The relative contribution of NO2 to dry deposition averaged from 19% in the peri-urban forests to 11% in the most natural site. During the monitoring period, the empirical critical loads provisionally proposed for ecosystem protection (10-20 kg N ha-1 year-1) was exceeded in three of the four studied forests.


Assuntos
Florestas , Nitrogênio/análise , Folhas de Planta/química , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Modelos Químicos , Espanha
5.
Environ Pollut ; 227: 194-206, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28460237

RESUMO

Mediterranean Basin ecosystems, their unique biodiversity, and the key services they provide are currently at risk due to air pollution and climate change, yet only a limited number of isolated and geographically-restricted studies have addressed this topic, often with contrasting results. Particularities of air pollution in this region include high O3 levels due to high air temperatures and solar radiation, the stability of air masses, and dominance of dry over wet nitrogen deposition. Moreover, the unique abiotic and biotic factors (e.g., climate, vegetation type, relevance of Saharan dust inputs) modulating the response of Mediterranean ecosystems at various spatiotemporal scales make it difficult to understand, and thus predict, the consequences of human activities that cause air pollution in the Mediterranean Basin. Therefore, there is an urgent need to implement coordinated research and experimental platforms along with wider environmental monitoring networks in the region. In particular, a robust deposition monitoring network in conjunction with modelling estimates is crucial, possibly including a set of common biomonitors (ideally cryptogams, an important component of the Mediterranean vegetation), to help refine pollutant deposition maps. Additionally, increased attention must be paid to functional diversity measures in future air pollution and climate change studies to establish the necessary link between biodiversity and the provision of ecosystem services in Mediterranean ecosystems. Through a coordinated effort, the Mediterranean scientific community can fill the above-mentioned gaps and reach a greater understanding of the mechanisms underlying the combined effects of air pollution and climate change in the Mediterranean Basin.


Assuntos
Poluentes Atmosféricos/análise , Atmosfera/química , Mudança Climática , Ecossistema , Monitoramento Ambiental , Poluição do Ar/estatística & dados numéricos , Biodiversidade , Clima , Humanos , Nitrogênio/análise , Pesquisa
6.
Environ Sci Pollut Res Int ; 24(34): 26213-26226, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28386886

RESUMO

To assess the impact of nitrogen (N) pollutants on forest ecosystems, the role of the interactions in the canopy needs to be understood. A great number of studies have addressed this issue in heavily N-polluted regions in north and central Europe. Much less information is available for the Iberian Peninsula, and yet this region is home to mountain forests and alpine grasslands that may be at risk due to excessive N deposition. To establish the basis for ecology-based policies, there is a need to better understand the forest response to this atmospheric impact. To fill this gap, in this study, we measured N deposition (as bulk, wet, and throughfall fluxes of dissolved inorganic nitrogen) and air N gas concentrations from 2011 to 2013 at four Spanish holm oak (Quercus ilex) forests located in different pollution environments. One site was in an area of intensive agriculture, two sites were influenced by big cities (Madrid and Barcelona, respectively), and one site was in a rural mountain environment 40 km north of Barcelona. Wet deposition ranged between 0.54 and 3.8 kg N ha-1 year-1 for ammonium (NH4+)-N and between 0.65 and 2.1 kg N ha-1 year-1 for nitrate (NO3-)-N, with the lowest deposition at the Madrid site for both components. Dry deposition was evaluated with three different approaches: (1) a canopy budget model based in throughfall measurements, (2) a branch washing method, and (3) inferential calculations. Taking the average dry deposition from these methods, dry deposition represented 51-67% (reduced N) and 72-75% (oxidized N) of total N deposition. Canopies retained both NH4+-N and NO3-N, with a higher retention at the agricultural and rural sites (50-60%) than at sites located close to big cities (20-35%, though more uncertainty was found for the site near Madrid), thereby highlighting the role of the forest canopy in processing N pollutant emissions.


Assuntos
Poluentes Atmosféricos/toxicidade , Florestas , Nitrogênio/toxicidade , Agricultura , Poluentes Atmosféricos/análise , Compostos de Amônio/análise , Compostos de Amônio/toxicidade , Cidades , Ecossistema , Monitoramento Ambiental/métodos , Europa (Continente) , Nitrogênio/química , Quercus/efeitos dos fármacos , Quercus/crescimento & desenvolvimento , Árvores/efeitos dos fármacos , Árvores/crescimento & desenvolvimento
7.
Environ Sci Pollut Res Int ; 24(34): 26259-26268, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28455565

RESUMO

Ozone (O3) critical levels have been established under the Long-Range Transboundary Air Pollution Convention to assess the risk of O3 effects in European vegetation. A recent review study has led to the development of O3 critical levels for annual Mediterranean pasture species using plants growing in well-watered pots at a coastal site and under low levels of competition. However, uncertainties remain in the extrapolation of the O3 sensitivity of these species under natural conditions. The response of two O3-sensitive annual Mediterranean pasture Trifolium species at the coastal site was compared with the response of the same species growing at a continental site, in natural soil and subject to water-stress and inter-specific competition, representing more closely their natural habitat. The slopes of exposure- and dose-response relationships derived for the two sites showed differences in the response to O3 between sites attributed to differences in environmental growing conditions, growing medium and the level of inter-specific competition, but the effect of the individual factors could not be assessed separately. Dose-based O3 indices partially explained differences due to environmental growing conditions between sites. The slopes showed that plants were more sensitive to O3 at the continental site, but homogeneity of slopes tests revealed that results from both experimental sites may be combined. Although more experimental data considering complex inter-specific competition situations and the effect of important interactive factors such as nitrogen would be needed, these results confirm the validity of applying the current flux-based O3 critical level under close to natural growing conditions. The AOT40-based O3 critical level derived at the coastal site was also considered a suitable risk indicator in close to natural growing conditions in the absence of soil moisture limitations on plant growth.


Assuntos
Poluentes Atmosféricos/toxicidade , Monitoramento Ambiental/métodos , Ozônio/toxicidade , Trifolium/efeitos dos fármacos , Poluentes Atmosféricos/análise , Ecossistema , Nitrogênio , Ozônio/análise
8.
Environ Sci Technol ; 51(3): 1147-1156, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28060487

RESUMO

Particulate matter (PM) deposited on Platanus acerifolia tree leaves has been sampled in the urban areas of 28 European cities, over 20 countries, with the aim of testing leaf deposited particles as indicator of atmospheric PM concentration and composition. Leaves have been collected close to streets characterized by heavy traffic and within urban parks. Leaf surface density, dimensions, and elemental composition of leaf deposited particles have been compared with leaf magnetic content, and discussed in connection with air quality data. The PM quantity and size were mainly dependent on the regional background concentration of particles, while the percentage of iron-based particles emerged as a clear marker of traffic-related pollution in most of the sites. This indicates that Platanus acerifolia is highly suitable to be used in atmospheric PM monitoring studies and that morphological and elemental characteristics of leaf deposited particles, joined with the leaf magnetic content, may successfully allow urban PM source apportionment.


Assuntos
Poluentes Atmosféricos , Material Particulado , Poluição do Ar , Cidades , Monitoramento Ambiental , Europa (Continente) , Tamanho da Partícula , Folhas de Planta/química
9.
Genome Announc ; 4(4)2016 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-27491989

RESUMO

Zika virus belongs to the genus Flavivirus, and its spread remains an international public health emergency. In this report, we describe the obtainment and molecular characterization of a complete viral genome through the direct metagenomic analysis from saliva from an autochthonous transmission case in Mexico.

10.
Environ Pollut ; 216: 653-661, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27344084

RESUMO

Atmospheric nitrogen deposition is one of the main threats for biodiversity and ecosystem functioning. Measurement techniques like ion-exchange resin collectors (IECs), which are less expensive and time-consuming than conventional methods, are gaining relevance in the study of atmospheric deposition and are recommended to expand monitoring networks. In the present work, bulk and throughfall deposition of inorganic nitrogen were monitored in three different holm oak forests in Spain during two years. The results obtained with IECs were contrasted with a conventional technique using bottle collectors and with a literature review of similar studies. The performance of IECs in comparison with the conventional method was good for measuring bulk deposition of nitrate and acceptable for ammonium and total dissolved inorganic nitrogen. Mean annual bulk deposition of inorganic nitrogen ranged 3.09-5.43 kg N ha(-1) according to IEC methodology, and 2.42-6.83 kg N ha(-1) y(-1) using the conventional method. Intra-annual variability of the net throughfall deposition of nitrogen measured with the conventional method revealed the existence of input pulses of nitrogen into the forest soil after dry periods, presumably originated from the washing of dry deposition accumulated in the canopy. Important methodological recommendations on the IEC method and discussed, compiled and summarized.


Assuntos
Compostos de Amônio/análise , Monitoramento Ambiental/métodos , Florestas , Nitratos/análise , Ciclo do Nitrogênio , Ecossistema , Resinas de Troca Iônica , Região do Mediterrâneo , Nitrogênio/análise , Quercus , Solo , Espanha
11.
Environ Pollut ; 213: 1007-1015, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26805742

RESUMO

The current levels of surface ozone (O3) are high enough to negatively affect trees in large regions of São Paulo State, southeastern Brazil, where standards for the protection of vegetation against the adverse effects of O3 do not exist. We evaluated three O3 metrics - phytotoxic ozone dose (POD), accumulated ozone exposure over the threshold of 40 ppb h (AOT40), and the sum of all hourly average concentrations (SUM00) - for the Brazilian native tropical tree species Astronium graveolens Jacq. We used the DO3SE (Deposition of Ozone for Stomatal Exchange) model and calculated PODY for different thresholds (from 0 to 6 mmol O3 m(-2) PLA s(-1)), evaluating the model's performance through the relationship between measured and modelled conductance. The response parameters were: visible foliar injury, considered as incidence (% injured plants), severity (% injured leaves in relation to the number of leaves on injured plants), and leaf abscission. The model performance was suitable and significant (R(2) = 0.58; p < 0.001). POD0 was better correlated to incidence and leaf abscission, and SUM00 was better correlated to severity. The highest values of O3 concentration-based metrics (AOT40 and SUM00) did not coincide with those of POD0. Further investigation may improve the model and contribute to the proposition of a national standard for the protection of native species.


Assuntos
Poluentes Atmosféricos/análise , Anacardiaceae/efeitos dos fármacos , Monitoramento Ambiental/métodos , Florestas , Ozônio/análise , Folhas de Planta/efeitos dos fármacos , Árvores/efeitos dos fármacos , Poluentes Atmosféricos/efeitos adversos , Anacardiaceae/crescimento & desenvolvimento , Brasil , Relação Dose-Resposta a Droga , Modelos Biológicos , Ozônio/efeitos adversos , Doenças das Plantas/induzido quimicamente , Folhas de Planta/crescimento & desenvolvimento , Estômatos de Plantas , Árvores/crescimento & desenvolvimento
12.
Environ Sci Pollut Res Int ; 23(7): 6400-13, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26620865

RESUMO

Peri-urban vegetation is generally accepted as a significant remover of atmospheric pollutants, but it could also be threatened by these compounds, with origin in both urban and non-urban areas. To characterize the seasonal and geographical variation of pollutant concentrations and to improve the empirical understanding of the influence of Mediterranean broadleaf evergreen forests on air quality, four forests of Quercus ilex (three peri-urban and one remote) were monitored in different areas in Spain. Concentrations of nitrogen dioxide (NO2), ammonia (NH3), nitric acid (HNO3) and ozone (O3) were measured during 2 years in open areas and inside the forests and aerosols (PM10) were monitored in open areas during 1 year. Ozone was the only air pollutant expected to have direct phytotoxic effects on vegetation according to current thresholds for the protection of vegetation. The concentrations of N compounds were not high enough to directly affect vegetation but could be contributing through atmospheric N deposition to the eutrophization of these ecosystems. Peri-urban forests of Q. ilex showed a significant below-canopy reduction of gaseous concentrations (particularly NH3, with a mean reduction of 29-38%), which indicated the feasibility of these forests to provide an ecosystem service of air quality improvement. Well-designed monitoring programs are needed to further investigate air quality improvement by peri-urban ecosystems while assessing the threat that air pollution can pose to vegetation.


Assuntos
Poluentes Atmosféricos/análise , Amônia/análise , Ácido Nítrico/análise , Dióxido de Nitrogênio/análise , Ozônio/análise , Poluição do Ar , Cidades , Monitoramento Ambiental , Florestas , Material Particulado/análise , Quercus/crescimento & desenvolvimento , Espanha , Tempo (Meteorologia)
13.
Environ Sci Pollut Res Int ; 22(14): 10873-81, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25772875

RESUMO

Phytotoxic ozone (O3) levels have been recorded in the Metropolitan Region of São Paulo (MRSP). Flux-based critical levels for O3 through stomata have been adopted for some northern hemisphere species, showing better accuracy than with accumulated ozone exposure above a threshold of 40 ppb (AOT40). In Brazil, critical levels for vegetation protection against O3 adverse effects do not exist. The study aimed to investigate the applicability of O3 deposition model (Deposition of Ozone for Stomatal Exchange (DO3SE)) to an O3-sensitive tropical tree species (Psidium guajava L. 'Paluma') under the MRSP environmental conditions, which are very unstable, and to assess the performance of O3 flux and AOT40 in relation to O3-induced leaf injuries. Stomatal conductance (g s) parameterization for 'Paluma' was carried out and used to calculate different rate thresholds (from 0 to 5 nmol O3 m(-2) projected leaf area (PLA) s(-1)) for the phytotoxic ozone dose (POD). The model performance was assessed through the relationship between the measured and modeled g sto. Leaf injuries were analyzed and associated with POD and AOT40. The model performance was satisfactory and significant (R (2) = 0.56; P < 0.0001; root-mean-square error (RMSE) = 116). As already expected, high AOT40 values did not result in high POD values. Although high POD values do not always account for more injuries, POD0 showed better performance than did AOT40 and other different rate thresholds for POD. Further investigation is necessary to improve our model and also to check if there is a critical level of ozone in which leaf injuries arise. The conclusion is that the DO3SE model for 'Paluma' is applicable in the MRSP as well as in temperate regions and may contribute to future directives.


Assuntos
Poluentes Atmosféricos/toxicidade , Ozônio/toxicidade , Psidium/efeitos dos fármacos , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Modelos Biológicos , Ozônio/análise , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/metabolismo , Psidium/metabolismo
14.
Bioresour Technol ; 154: 305-12, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24412482

RESUMO

The acclimatization and performance study of lixiviation of sugar beet pulp are carried out in upflow anaerobic fixed bed reactor in thermophilic range of temperature (55°C). Several hydraulic retention time is conducted (11, 8, 6, 4, 2, and 1.5 days). The performance study showed that Chemical Oxygen Demand removal efficiency is 90% for 6 days-HRT. While COD removal efficiency was reduced within the range of 74.3% and 59.4% in others HRT. Organic loading rates greater than 10 kg COD/m(3)d in influent, (2 days-HRT), produces a destabilization of the process due to total acidity accumulation in reactors although is the HRT with highest methane production. The results showed that an increase in OLR was directly correlated with active biomass inside reactor but not with the amount in microbial community. The bacterial concentration inside the reactor is strongly influenced by the content of microorganisms in the lixiviation of sugar beet pulp.


Assuntos
Beta vulgaris/química , Reatores Biológicos/microbiologia , Biotecnologia/instrumentação , Biotecnologia/métodos , Temperatura , Anaerobiose , Bactérias/crescimento & desenvolvimento , Biocombustíveis , Análise da Demanda Biológica de Oxigênio , Concentração de Íons de Hidrogênio , Metano/metabolismo , Volatilização , Eliminação de Resíduos Líquidos
15.
BMC Evol Biol ; 13: 115, 2013 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-23738626

RESUMO

BACKGROUND: Species with strict ecological requirements may provide new insights into the forces that shaped the geographic variation of genetic diversity. The Pyrenean desman, Galemys pyrenaicus, is a small semi-aquatic mammal that inhabits clean streams of the northern half of the Iberian Peninsula and is endangered in most of its geographic range, but its genetic structure is currently unknown. While the stringent ecological demands derived from its aquatic habitat might have caused a partition of the genetic diversity among river basins, Pleistocene glaciations would have generated a genetic pattern related to glacial refugia. RESULTS: To study the relative importance of historical and ecological factors in the genetic structure of G. pyrenaicus, we used mitochondrial and intronic sequences of specimens covering most of the species range. We show, first, that the Pyrenean desman has very low levels of genetic diversity compared to other mammals. In addition, phylogenetic and dating analyses of the mitochondrial sequences reveal a strong phylogeographic structure of a Middle Pleistocene origin, suggesting that the main lineages arose during periods of glacial isolation. Furthermore, both the spatial distribution of nuclear and mitochondrial diversity and the results of species distribution modeling suggest the existence of a major glacial refugium in the northwestern part of the Iberian Peninsula. Finally, the main mitochondrial lineages show a striking parapatric distribution without any apparent exchange of mitochondrial haplotypes between the lineages that came into secondary contact (although with certain permeability to nuclear genes), indicating incomplete mixing after the post-glacial recolonization. On the other hand, when we analyzed the partition of the genetic diversity among river basins, the Pyrenean desman showed a lower than expected genetic differentiation among main rivers. CONCLUSIONS: The analysis of mitochondrial and intronic markers in G. pyrenaicus showed the predominant effects of Pleistocene glaciations on the genetic structure of this species, while the distribution of the genetic diversity was not greatly influenced by the main river systems. These results and, particularly, the discovery of a marked phylogeographic structure, may have important implications for the conservation of the Pyrenean desman.


Assuntos
Organismos Aquáticos/genética , Evolução Biológica , Insetívoros/genética , Animais , Organismos Aquáticos/classificação , Sequência de Bases , Ecossistema , Espécies em Perigo de Extinção , Deriva Genética , Variação Genética , Haplótipos , Insetívoros/classificação , Dados de Sequência Molecular , Filogenia , Filogeografia
16.
J Dairy Res ; 80(1): 51-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23253470

RESUMO

Hispánico cheese, manufactured from a mixture of cow and ewe milk, is representative of cheese varieties made using milk from more than one animal species in Mediterranean countries. The shortage of ewe milk production in autumn hinders the uniformity of Hispánico cheese composition throughout the year. To surmount this inconvenience of ewe milk seasonality, curds made in spring from raw and pasteurized ewe milk were stored frozen and used four months later for the manufacture of Hispánico cheese. Experimental cheeses were made by mixing fresh curd from pasteurized cow milk with thawed curd from raw or pasteurized ewe milk, and control cheese from a mixture of pasteurized cow and ewe milk in the same proportion. Characteristics of experimental and control cheeses throughout a 60-d ripening period were investigated. On the one hand, the experimental cheese containing frozen curd from raw ewe milk showed the highest counts of staphylococci, Gram-negative bacteria and coliforms, the highest levels of aminopeptidase and esterase activity, and the highest concentrations of free amino acids, free fatty acids, alcohols and esters. On the other, the experimental cheese containing frozen curd from pasteurized ewe milk had concentrations of free amino acids, free fatty acids and volatile compounds similar to those of control cheese, with the only exception being a higher level of ketones. Flavour intensity reached the highest scores in the experimental cheese containing frozen curd from raw ewe milk, followed by the experimental cheese containing frozen curd from pasteurized ewe milk. Flavour quality scores of both experimental cheeses were similar, and lower than those of control cheese.


Assuntos
Queijo/análise , Conservação de Alimentos/métodos , Leite , Sensação , Ovinos , Compostos Orgânicos Voláteis/análise , Aminoácidos/análise , Animais , Queijo/microbiologia , Ácidos Graxos não Esterificados/análise , Feminino , Manipulação de Alimentos/métodos , Congelamento , Cetonas/análise , Lipólise , Leite/enzimologia , Pasteurização , Peptídeo Hidrolases/análise , Proteólise , Paladar
17.
Environ Pollut ; 159(8-9): 2138-47, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21269745

RESUMO

Tropospheric ozone (O(3)) is considered one of the most important air pollutants affecting human health. The role of peri-urban vegetation in modifying O(3) concentrations has been analyzed in the Madrid region (Spain) using the V200603par-rc1 version of the CHIMERE air quality model. The 3.7 version of the MM5 meteorological model was used to provide meteorological input data to the CHIMERE. The emissions were derived from the EMEP database for 2003. Land use data and the stomatal conductance model included in CHIMERE were modified according to the latest information available for the study area. Two cases were considered for the period April-September 2003: (1) actual land use and (2) a fictitious scenario where El Pardo peri-urban forest was converted to bare-soil. The results show that El Pardo forest constitutes a sink of O(3) since removing this green area increased O(3) levels over the modified area and over down-wind surrounding areas.


Assuntos
Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos , Modelos Químicos , Árvores/fisiologia , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/metabolismo , Cidades , Ozônio/análise , Ozônio/metabolismo , Espanha , Árvores/classificação , Árvores/metabolismo
19.
Environ Pollut ; 155(3): 473-80, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18342418

RESUMO

A sensitivity analysis of a proposed parameterization of the stomatal conductance (g(s)) module of the European ozone deposition model (DO(3)SE) for Quercus ilex was performed. The performance of the model was tested against measured g(s) in the field at three sites in Spain. The best fit of the model was found for those sites, or during those periods, facing no or mild stress conditions, but a worse performance was found under severe drought or temperature stress, mostly occurring at continental sites. The best performance was obtained when both f(phen) and f(SWP) were included. A local parameterization accounting for the lower temperatures recorded in winter and the higher water shortage at the continental sites resulted in a better performance of the model. The overall results indicate that two different parameterizations of the model are needed, one for marine-influenced sites and another one for continental sites.


Assuntos
Poluentes Atmosféricos/metabolismo , Oxidantes Fotoquímicos/metabolismo , Ozônio/metabolismo , Estômatos de Plantas/fisiologia , Quercus/metabolismo , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Geografia , Modelos Biológicos , Oxidantes Fotoquímicos/análise , Ozônio/análise , Transpiração Vegetal , Estações do Ano , Espanha
20.
ScientificWorldJournal ; 7 Suppl 1: 119-27, 2007 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-17450288

RESUMO

An ozone (O3) deposition model (DO3SE) is currently used in Europe to define the areas where O3 concentrations lead to absorbed O3 doses that exceed the flux-based critical levels above which phytotoxic effects would be likely recorded. This mapping exercise relies mostly on the accurate estimation of O3 flux through plant stomata. However, the present parameterization of the modulation of stomatal conductance (g(s)) behavior by different environmental variables needs further adjustment if O3 phytotoxicity is to be assessed accurately at regional or continental scales. A new parameterization of the model is proposed for Holm oak (Quercus ilex), a tree species that has been selected as a surrogate for all Mediterranean evergreen broadleaf species. This parameterization was based on a literature review, and was calibrated and validated using experimentally measured data of g(s) and several atmospheric and soil parameters recorded at three sites of the Iberian Peninsula experiencing long summer drought, and very cold and dry winter air (El Pardo and Miraflores) or milder conditions (Tietar). A fairly good agreement was found between modeled and measured data (R2 = 0.64) at Tietar. However, a reasonable performance (R2 = 0.47-0.62) of the model was only achieved at the most continental sites when g(s) and soil moisture deficit relationships were considered. The influence of root depth on g(s) estimation is discussed and recommendations are made to build up separate parameterizations for continental and marine-influenced Holm oak sites in the future.


Assuntos
Poluentes Atmosféricos/metabolismo , Modelos Biológicos , Ozônio/metabolismo , Quercus/metabolismo , Poluentes Atmosféricos/toxicidade , Atmosfera , Calibragem , Monitoramento Ambiental , Região do Mediterrâneo , Ozônio/toxicidade , Epiderme Vegetal/metabolismo , Folhas de Planta/metabolismo , Quercus/efeitos dos fármacos , Solo
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