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1.
J Synchrotron Radiat ; 25(Pt 3): 874-877, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29714199

RESUMEN

Damselflies Calopteryx haemorrhoidalis exhibiting black wings are found in the western Mediterranean, Algeria, France, Italy, Spain and Monaco. Wing pigmentation is caused by the presence of melanin, which is involved in physiological processes including defence reactions, wound healing and sclerotization of the insect. Despite the important physiological roles of melanin, the presence and colour variation among males and females of the C. haemorrhoidalis species and the localization of the pigment within the wing membrane remain poorly understood. In this study, infrared (IR) microspectroscopy, coupled with the highly collimated synchrotron IR beam, was employed in order to identify the distribution of the pigments in the wings at a high spatial resolution. It was found that the melanin is localized in the procuticle of the C. haemorrhoidalis damselfly wings, distributed homogeneously within this layer, and not associated with the lipids of the epicuticle.


Asunto(s)
Proteínas de Insectos/metabolismo , Melaninas/metabolismo , Alas de Animales/metabolismo , Animales , Análisis de Fourier , Masculino , Odonata , Espectrofotometría Infrarroja/métodos , Sincrotrones
2.
Appl Microbiol Biotechnol ; 101(11): 4683-4690, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28246886

RESUMEN

Nanostructured insect wing surfaces have been reported to possess the ability to resist bacterial colonization through the mechanical rupture of bacterial cells coming into contact with the surface. In this work, the susceptibility of physiologically young, mature and old Staphylococcus aureus CIP 65.8 and Pseudomonas aeruginosa ATCC 9721 bacterial cells, to the action of the bactericidal nano-pattern of damselfly Calopteryx haemorrhoidalis wing surfaces, was investigated. The results were obtained using several surface characterization techniques including optical profilometry, scanning electron microscopy, synchrotron-sourced Fourier transform infrared microspectroscopy, water contact angle measurements and antibacterial assays. The data indicated that the attachment propensity of physiologically young S. aureus CIP 65.8T and mature P. aeruginosa ATCC 9721 bacterial cells was greater than that of the cells at other stages of growth. Both the S. aureus CIP 65.8T and P. aeruginosa ATCC 9721 cells, grown at the early (1 h) and late stationary phase (24 h), were found to be most susceptible to the action of the wings, with up to 89.7 and 61.3% as well as 97.9 and 97.1% dead cells resulting from contact with the wing surface, respectively.


Asunto(s)
Nanoestructuras , Odonata/microbiología , Pseudomonas aeruginosa/fisiología , Staphylococcus aureus/fisiología , Alas de Animales/microbiología , Animales , Microscopía Electrónica de Rastreo , Pseudomonas aeruginosa/crecimiento & desarrollo , Staphylococcus aureus/crecimiento & desarrollo , Propiedades de Superficie , Alas de Animales/ultraestructura
3.
J Colloid Interface Sci ; 603: 886-897, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34265480

RESUMEN

HYPOTHESIS: The ability exhibited by insect wings to resist microbial infestation is a unique feature developed over 400 million years of evolution in response to lifestyle and environmental pressures. The self-cleaning and antimicrobial properties of insect wings may be attributed to the unique combination of nanoscale structures found on the wing surface. EXPERIMENTS: In this study, we characterised the wetting characteristics of superhydrophobic damselfly Calopteryx haemorrhoidalis wings. We revealed the details of air entrapment at the micro- and nano scales on damselfly wing surfaces using a combination of spectroscopic and electron microscopic techniques. Cryo-focused-ion-beam scanning electron microscopy was used to directly observe fungal spores and conidia that were unable to cross the air-liquid interface. By contrast, bacterial cells were able to cross the air-water interface to be ruptured upon attachment to the nanopillar surface. The robustness of the air entrapment, and thus the wing antifungal behaviour, was demonstrated after 1-week of water immersion. A newly developed wetting model confirmed the strict Cassie-Baxter wetting regime when damselfly wings are immersed in water. FINDINGS: We provide evidence that the surface nanopillar topography serves to resist both fungal and bacterial attachment via a dual action: repulsion of fungal conidia while simultaneously killing bacterial cells upon direct contact. These findings will play an important role in guiding the fabrication of biomimetic, anti-fouling surfaces that exhibit both bactericidal and anti-fungal properties.


Asunto(s)
Antifúngicos , Odonata , Animales , Antibacterianos/farmacología , Humectabilidad , Alas de Animales
4.
Sci Rep ; 8(1): 8413, 2018 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-29849036

RESUMEN

Insects represent the majority of known animal species and exploit a variety of fascinating nanotechnological concepts. We investigated the wings of the damselfly Calopteryx haemorrhoidalis, whose males have dark pigmented wings and females have slightly pigmented wings. We used scanning electron microscopy (SEM) and nanoscale synchrotron X-ray fluorescence (XRF) microscopy analysis for characterizing the nanostructure and the elemental distribution of the wings, respectively. The spatially resolved distribution of the organic constituents was examined by synchrotron Fourier transform infrared (s-FTIR) microspectroscopy and subsequently analyzed using hierarchical cluster analysis. The chemical distribution across the wing was rather uniform with no evidence of melanin in female wings, but with a high content of melanin in male wings. Our data revealed a fiber-like structure of the hairs and confirmed the presence of voids close to its base connecting the hairs to the damselfly wings. Within these voids, all detected elements were found to be locally depleted. Structure and elemental contents varied between wing membranes, hairs and veins. The elemental distribution across the membrane was rather uniform, with higher Ca, Cu and Zn levels in the male damselfly wing membranes.


Asunto(s)
Odonata/anatomía & histología , Espectrometría por Rayos X/instrumentación , Espectroscopía Infrarroja por Transformada de Fourier/instrumentación , Sincrotrones , Alas de Animales/química , Animales , Femenino , Masculino
5.
ACS Omega ; 3(6): 6039-6046, 2018 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-30221231

RESUMEN

Dragonfly wings are of great interest to researchers investigating biomimetic designs for antiwetting and antibacterial surfaces. The waxy epicuticular layer on the membrane of dragonfly wings possesses a unique surface nanoarchitecture that consists of irregular arrays of nanoscale pillars. This architecture confers superhydrophobic, self-cleaning, antiwetting, and antibiofouling behaviors. There is some evidence available that suggests that lifestyle factors may have influenced the evolution of the wing nanostructures and, therefore, the resulting properties of the wings; however, it appears that no systematic studies have been performed that have compared the wing surface features across a range of dragonfly species. Here, we provided a comparison of relevant wing surface characteristics, including chemical composition, wettability, and nanoarchitecture, of seven species of dragonfly from three families including Libellulidae, Aeshnidae, and Gomphidae. The characteristic nanopillar arrays were found to be present, and the chemical composition and the resultant wing surface superhydrophobicity were found to be well-conserved across all of the species studied. However, subtle differences were observed between the height, width, and density of nanofeatures and water droplet bouncing behavior on the wing surfaces. The results of this research will contribute to an understanding of the physical and chemical surface features that are optimal for the design of antiwetting and antibacterial surfaces.

6.
PhytoKeys ; (77): 41-62, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28814919

RESUMEN

This data paper describes a specimens' dataset of the Catalonian threatened vascular plants conserved in five public Catalonian herbaria (BC, BCN, HGI, HBIL and MTTE). Catalonia is an administrative region of Spain that includes large autochthon plants diversity and 199 taxa with IUCN threatened categories (EX, EW, RE, CR, EN and VU). This dataset includes 1,618 records collected from 17th century to nowadays. For each specimen, the species name, locality indication, collection date, collector, ecology and revision label are recorded. More than 94% of the taxa are represented in the herbaria, which evidence the paper of the botanical collections as an essential source of occurrence data.

7.
Aten Primaria ; 40(12): 617-21, 2008 Dec.
Artículo en Español | MEDLINE | ID: mdl-19100149

RESUMEN

OBJECTIVE: To determine the overall prevalence of the chronic use of benzodiazepines and similar drugs in primary care. DESIGN: Observational, cross-sectional study. SETTING: Healthcare centres of the Reus-Altebrat Primary Care Service, Tarragona, Spain. PARTICIPANTS: Patients older than 15 years, on prolonged treatment with benzodiazepines or similar drugs. MEASUREMENTS: The variables studied were age, sex, type of healthcare centre (rural or urban), benzodiazepine, or similar drug administered and duration of treatment. RESULTS. There were 6885 patients who were on prolonged benzodiazepine or similar drug treatment, of which 70.9% were female, 73.4% were 65 years or older, and 73% attended an urban centre. The overall prevalence was 6.9%, and was higher among women than men (9.7% and 4%, respectively), and increased with age up to 27.3% among patients of 75 years or more. The stratified results showed that chronic consumption was higher among women 75 years of age or older attached to urban healthcare centres, with a prevalence of 35.7%. CONCLUSIONS: A high percentage of our population, which includes the most fragile patients, use benzodiazepines or a similar drug in a way that is not consistent with the recommendations of clinical practice guidelines.


Asunto(s)
Benzodiazepinas/uso terapéutico , Adolescente , Adulto , Anciano , Estudios Transversales , Utilización de Medicamentos/estadística & datos numéricos , Femenino , Instituciones de Salud , Humanos , Masculino , Persona de Mediana Edad , Atención Primaria de Salud , Factores Sexuales , Población Urbana , Adulto Joven
8.
Aten. prim. (Barc., Ed. impr.) ; 40(12): 617-621, dic. 2008. ilus, tab
Artículo en Es | IBECS (España) | ID: ibc-70380

RESUMEN

Objetivo. Determinar la prevalencia globaldel consumo crónico de benzodiacepinasy sus análogos en atención primaria.Diseño. Estudio transversal observacional.Emplazamiento. Centros de salud del Serviciode Atención Primaria Reus-Altebrat.Participantes. Pacientes con edad superiora 15 años, en tratamiento prolongadocon benzodiacepinas o sus análogos.Mediciones. Las variables analizadas fueron laedad, el sexo, el tipo de centro de salud (ruralo urbano), la benzodiacepina o el análogoadministrados y la duración del tratamiento.Resultados. Habían utilizado unabenzodiacepina o un análogo de formaprolongada 6.885 pacientes. El 70,9% eranmujeres, el 73,4% tenía 65 años o más, y el73% estaba adscrito a un centro urbano. Laprevalencia global fue del 6,9%, mayor entrelas mujeres que entre los varones (9,7% y 4%,respectivamente), y aumentó con la edadhasta un 27,3% entre los pacientes de 75 omás años. En los resultados estratificados seobservó que el consumo crónico era superiorentre las mujeres de 75 o más años de edadadscritas a centros de salud urbanos, conuna prevalencia del 35,7%.Conclusiones. Un porcentaje elevado de lapoblación, que comprende a los pacientesmás frágiles, está siendo tratado conbenzodiacepinas o análogos, lo que no seajusta a las recomendaciones de las guíasde práctica clínica


Objective. To determine the overallprevalence of the chronic use ofbenzodiazepines and similar drugsin primary care.Design. Observational, cross-sectional study.Setting. Healthcare centres of the Reus-Altebrat Primary Care Service,Tarragona,Spain.Participants. Patients older than 15 years, onprolonged treatment with benzodiazepinesor similar drugs.Measurements. The variables studied wereage, sex, type of healthcare centre (rural orurban), benzodiazepine, or similar drugadministered and duration of treatment.Results. There were 6885 patients who wereon prolonged benzodiazepine or similardrug treatment, of which 70.9% werefemale, 73.4% were 65 years or older, and73% attended an urban centre. The overallprevalence was 6.9%, and was higher amongwomen than men (9.7% and 4%,respectively), and increased with age up to27.3% among patients of 75 years or more.The stratified results showed that chronicconsumption was higher among women75 years of age or older attached to urbanhealthcare centres, with a prevalence of35.7%.Conclusions. A high percentage of ourpopulation, which includes the most fragilepatients, use benzodiazepines or a similardrug in a way that is not consistent withthe recommendations of clinical practiceguidelines


Asunto(s)
Humanos , Femenino , Anciano , Benzodiazepinas/administración & dosificación , Benzodiazepinas/efectos adversos , Benzodiazepinas/uso terapéutico , Atención Primaria de Salud/ética , Atención Primaria de Salud/organización & administración , Salud del Anciano , Ansiolíticos/efectos adversos , Ansiolíticos/uso terapéutico , Utilización de Medicamentos/clasificación , Utilización de Medicamentos/ética , Anciano/fisiología
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