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921.
Nuno Marques Ana Lebre Francisco Marques Maria Julião Luís Freitas Lurdes Malcata Eduardo Rabadão José Saraiva da Cunha 《Mycopathologia》2013,176(1-2):89-93
The authors report a clinical case of an isolated oral histoplasmosis in a hemodialysis patient that presented with fever of unknown origin and had an unremarkable physical examination. During the investigation, a Gallium scan showed uptake in the oral cavity and soon after the oral cavity examination revealed a granulomatous lesion on the tooth 26. Histopathologic findings were compatible with histoplasmosis. The treatment regimen included liposomal amphotericin B followed by itraconazole consolidation therapy, and side effects did not occur. Both clinical evolution and outcome were favorable. Oral histoplasmosis in a non-immunosuppressed patient is extremely rare. 相似文献
922.
Ana Paula Souza Caetano Daniela Guimarães Simão Renata Carmo-Oliveira Paulo Eugênio Oliveira 《Plant Systematics and Evolution》2013,299(7):1253-1262
Apomixis, or asexual reproduction through seeds, has been reported for species of the tribe Miconieae, Melastomataceae, but details of the process have yet to be described. We analyzed and compared sporogenesis and gametogenesis in the apomictic Miconia albicans and the sexual M. chamissois. The results point to some differences between species, which were related to the apomictic process. In M. albicans microsporogenesis, problems during meiosis and degeneration of its products led to total pollen sterility, while M. chamissois presented normal bicellular pollen grains in the mature anther. The absence or abnormality of meiosis in M. albicans megasporogenesis led to the formation of an unreduced embryo sac and also to egg cell parthenogenesis, which gave rise to the apomictic embryo. Embryo and endosperm development were autonomous, resulting in seeds and fruits independent of pollination and fertilization. Thus, in this species, apomixis can be classified as diplosporic and obligate. In contrast, meiosis was as expected in the sexual M. chamissois, and led to the development of a reduced embryo sac. Despite the divergent pathways, many embryological characteristics were similar between the studied species and other Melastomataceae and they seem to be conservative character states for the family. 相似文献
923.
Juan Moreno Alberto Velando Rafael Ruiz-de-Castañeda Sonia González-Braojos Alejandro Cantarero 《Acta ethologica》2013,16(2):65-75
Badges of status may be controlled by costs derived from increased aggression from dominant individuals. This cost could be translated into elevated metabolic levels and a concomitant disruption of oxidative balance. Some females in Iberian pied flycatcher Ficedula hypoleuca populations exhibit a white forehead patch similar to that exhibited by all males in this species, functioning in aggressive interactions between females when competing for breeding sites. To test if social stress imposes costs on signalling, we painted white patches on females without natural patches (NP) and compared them with females with natural control (NU). We also over-painted the natural patch in other females (FP) and compared to females with control natural patches (FU). We obtained for the whole sample of females data on reproductive investment, morphology and oxidative damage measured by blood malondialdehydes (MDA), and in a subsample of females variables related to parental care during incubation and the early nestling stage. FP and FU did not differ significantly in any variable which negates an effect of paint itself. However, NP females showed significant higher levels of MDA than NU females when controlling for breeding success for the whole sample, and for female incubation attendance for the parental care subsample. When including the four treatments, there was a significant interaction between the paint treatment and the presence/absence of badges before the experiment when controlling for the significant negative effect of incubation attendance on MDA. Addition of a badge to females without one leads to increased oxidative damage possibly mediated by social control. Badges of status in female pied flycatchers may operate as badges of oxidative status. 相似文献
924.
Pedro H. C. Pereira João L. L. Feitosa Diego V. Medeiros Beatrice P. Ferreira 《Acta ethologica》2013,16(1):53-56
Fishes associated in schools acquire adaptive advantages by grouping together, e.g., access to a larger variety of food resources, foraging sites, and protection against potential predators. This work presents the first record of a feeding association between the bucktooth parrotfish, Sparisoma radians and the sailor’s grunt Haemulon parra, on Tamandaré reefs, Southwestern Atlantic. Through this association, S. radians gained access to otherwise unavailable food resources to be found inside territorial damselfish domain, thus characterizing an event of foraging facilitation. 相似文献
925.
We describe a new genus and species of hadrosaurid dinosaur, Latirhinus uitstlani, from upper Campanian strata of the Cerro del Pueblo Formation in northern Mexico. The new taxon differs from other hadrosaurids, except Gryposaurus, in possessing a deep and arcuate dorsal process of the nasal; it differs from Gryposaurus, as well as from all other saurolophines, in having a broader narial foramen, and an anterodorsally curved deltoid crest of the scapula (convergent with Lambeosaurinae within the context of Hadrosauridae). L. uitstlani appears to be allied to ‘kritosaurs’, particularly to species of Gryposaurus, and it represents one of the southernmost saurolophines of North America. Likewise, L. uitstlani adds to the diversity of saurolophines in the southern Western Interior Basin and its occurrence in northern Mexico is consistent with the apparent predominance of ‘kritosaurs’ in southern Laramidia during late Campanian times. 相似文献
926.
Penélope Cruzado-Caballero José Ignacio Ruiz-Omeñaca Rodrigo Gaete Violeta Riera Oriol Oms José Ignacio Canudo 《Historical Biology》2013,25(5):619-630
In the latest Maastrichtian, the European hadrosauroid fauna was more diverse than those of North America and Asia. The European record of hadrosaurid dentaries is an example of this diversity, and most of the sites with mandibular remains are located in the Ibero-Armorican Realm. Within the Iberian Peninsula, most of the remains are located in the Tremp Basin (South Central Pyrenees). Two of the three valid hadrosaurid taxa defined in this basin are from the Blasi sites (Arén, Huesca province): Arenysaurus ardevoli (Blasi-3) and Blasisaurus canudoi (Blasi-1). A new locality in Blasi (Blasi 3.4) has provided a new dentary from an indeterminate euhadrosaurid. This dentary presents some characters intermediate between Arenysaurus and Blasisaurus, some characters similar to Pararhabdodon isonensis (from the nearby province of Lleida), and some characters of its own. Nevertheless, due to its fragmentary character, without dentition or its edentulous anterior part, it cannot be determined above the level of Euhadrosauria. It thus represents a fourth Iberian euhadrosaurian taxon in the Ibero-Armorican Realm, different from Arenysaurus, Blasisaurus and Pararhabdodon, increasing the diversity of hadrosauroids in this realm at the very end of the Cretaceous. 相似文献
927.
In this paper, we describe the taphofacies and ichnofacies from Aptian strata of the San Juan Raya Formation in the Santa Ana Teloxtoc area, Puebla, Mexico. A composite stratigraphic section was analysed on a bed-by-bed scale up to a total thickness of 765.5 m. Our results show the presence of 10 taphofacies and 3 ichnofacies. The taphofacies and ichnofacies interpretation, and its correlation with the sedimentary lithofacies, enabled the determination of a palaeoenvironmental model for the study area that corresponds to a shallow marine, open-coast, clastic system with episodic sedimentation as a product of storm events. This system had several variations in sub-environments, from foreshore to offshore. Foreshore and shoreface environments are characterised by taphofacies Tf1, Tf2, Tf3 and Tf10 and PsI and SkI ichnofacies, representing lower faunal diversity moments (with the exception of Tf3 taphofacies). Meanwhile, taphofacies Tf4, Tf5, Tf6, Tf7, Tf8 and Tf9 were representative of shelf environments and are described as moments of medium-to-high faunal diversity (with the exception of Tf5 taphofacies). 相似文献
928.
Due to the refractory nature of pathogenic microbial biofilms, innovative biofilm eradication strategies are constantly being sought. Thus, this study addresses a novel approach to eradicate Pseudomonas aeruginosa biofilms. Magnetic nanoparticles (MNP), ciprofloxacin (Cipro), and magnetic fields were systematically evaluated in vitro for their relative anti-biofilm contributions. Twenty-four-hour biofilms exposed to aerosolized MNPs, Cipro, or a combination of both, were assessed in the presence or absence of magnetic fields (Static one-sided, Static switched, Oscillating, Static + oscillating) using changes in bacterial metabolism, biofilm biomass, and biofilm imaging. The biofilms exposed to magnetic fields alone exhibited significant metabolic and biomass reductions (p < 0.05). When biofilms were treated with a MNP/Cipro combination, the most significant metabolic and biomass reductions were observed when exposed to static switched magnetic fields (p < 0.05). The exposure of P. aeruginosa biofilms to a static switched magnetic field alone, or co-administration with MNP/Cipro/MNP + Cipro appears to be a promising approach to eradicate biofilms of this bacterium. 相似文献
929.
Glutaraldehyde (GTA) is a widely used biocide due to its high effectiveness. The experimental work reported here was carried out to assess the effectiveness of GTA in controlling biofilms formed by Pseudomonas fluorescens on stainless steel slides, and to compare efficacy against both planktonic and sessile micro‐rganisms. The tests were performed using two concentrations of GTA (50 and 100mg 1‐1), biofilms of two ages (7 and 15 d), several pH values (5,7 and 9) and a range of exposure times (from 0 (control) to 1,3,7 and 24 h). The action of GTA on biofilm and planktonic populations was assessed by means of activity tests, zeta potential, and the wet weight of the biofilms. Biofilms were not completely removed after treatment with GTA in any of the conditions studied. The higher GTA concentration was more effective in reducing the bacterial activity of the biofilm. The biocide proved to be more effective for longer exposure times. GTA showed good antimicrobial activity against P. fluorescens in suspension, with higher activity at pH 9. The findings of this study suggest that when GTA is used to control biofilms, it reacts with one of the components of the matrix, the proteins, thereby reducing its antimicrobial action. 相似文献
930.
João Gabriel Silva Souza Carolina Veloso Lima Bárbara Emanoele Costa Oliveira Antônio Pedro Ricomini-Filho Marcelo Faveri Cortino Sukotjo 《Biofouling》2013,29(10):1175-1184
AbstractThis study aimed to test the dose-response effect of chlorhexidine on multispecies biofilms formed on commercially pure titanium (cpTi) and titanium-zirconium (TiZr) alloy. Biofilms were formed on cpTi and TiZr discs and treated two times per day with five different chlorhexidine concentrations (0.12, 0.20, 0.50, 1, 2%). The biofilms were collected for microbiological, biochemical and microscopic analyses. The significance of differences among groups was evaluated by linear regression, ANOVA, Bonferroni and Tukey tests. The mean number of colony-forming units decreased as the chlorhexidine concentration increased for both cpTi and TiZr (p?<?0.05). The maximum effect was observed with the 0.5% concentration. Confocal microscopy images suggested an increase in the number of dead bacterial cells with increased chlorhexidine concentration. The biofilm pH increased after chlorhexidine exposure (p?<?0.05). Chlorhexidine showed an antimicrobial dose-response effect in controlling biofilm on cpTi and TiZr. 0.5% chlorhexidine can be used to achieve the maximum antimicrobial effect on both materials. 相似文献