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941.
Three new species of Dahlstedtia, D. burkartii, D. dehiscens, and D. lewisiana, are described from South America, and their relationships with related species are discussed. Dahlstedtia burkartii, from Argentina, has pink flowers with standard straight, whereas D. dehiscens and D. lewisiana, both from Brazil, have purplish to lilac flowers with a reflexed standard petal. A new combination, Dahlstedtia peckoltii, is proposed based on Lonchocarpus peckoltii and a neotype is selected for the latter. Information about geographic distribution and phenology of the species is provided. 相似文献
942.
About 10,000 years ago subsistence farmers started to domesticate plants and it was only much later, after the discovery of the fundaments of genetics, those organisms were submitted to rational genetic improvement mainly by selecting of traits of interest. Breeders used appropriate gene combinations to produce new animal races, plant varieties and hybrids, as well as improved microorganisms such as yeasts. After the introduction of recombinant DNA techniques, the transfer of DNA between species belonging to different genera, families or kingdoms became possible. The release of transgenic plants has aroused debates about several aspects of the environmental and human risks that could result from the introduction of genetically modified crops. Less effort has been dedicated to evaluate the impact of transgenic plants on their associated microorganisms, some of which (e.g. nitrogen-fixing bacteria, mycorrhizal fungi and endophytic microbiota) are extremely important for the survival of the plant. Investigations have been made regarding the horizontal transfer of genetic material between transgenic plants and microorganisms and on the disturbance of useful symbiotic associations between plants and endophytic, epiphytic and rhizosphere communities. In most cases the results do no show any adverse effect of transgenic plants on autochthonous plant-associated microorganisms. Results from our laboratory show small changes caused by genetically modified endophytic bacteria on the indigenous endophytic population of the sweet orange Citrus sinensis. In tests using appropriated fungal strains preliminary results using extracts from transgenic plants indicate that these plants do not affect haploidization, mitotic crossing-over, mutation rate or chromosomal alterations. 相似文献
943.
Cristiano Schetini de Azevedo João Bosco Ferraz Herlandes Penha Tinoco Robert John Young Marcos Rodrigues 《Acta ethologica》2010,13(2):109-117
The aim of this study was to evaluate activity–time budget, habitat use and how seasonality and group size influence the expression of greater rhea behaviours. Greater rheas are threatened South American birds; habitat loss, predation and hunting are the main factors responsible for population declines. The study was conducted in farmlands within a matrix of commercial Eucalyptus plantation and remnants of natural habitats of cerrado vegetation (savannah-like) in southeastern Brazil. Rhea groups were located visually in different habitats visited monthly from January 2004 to December 2005. Time spent searching greater rheas in each habitat was equally distributed. Data were collected using scan sampling with instantaneous recording of behaviours every minute. The time–activity budget of greater rheas was influenced by habitat structure, time of the day, season and group size. Rheas spent more time in open areas than in forested areas (p < 0.001). Vigilance behaviours were more displayed in forested areas, in the dry season and by solitary and small groups of birds. Resting behaviours occurred more often in open lands and within groups with more than three rheas. Food availability, good visibility and low human presence are the possible factors for the preference of greater rheas for pasturelands. The results support the resource availability hypothesis, where it is expected that habitats with a higher food availability will be more used by the animals, group size hypothesis, where the scarcity of resources will lead to smaller groups of animals and that forestry modifies greater rheas habitat use and behaviours. 相似文献
944.
Goussia lusca n. sp. is described from the liver of pouting Trisopterus luscus from the NE Atlantic Ocean in Ibero-Atlantic Portuguese and Spanish waters. Mature oocysts were 31.7 (28.8 to 35.4) microm in diameter. Each oocyst contained 4 ellipsoidal sporocysts arranged in an aleatory position, and measuring approximately 13.7 x 9.2 microm. Each sporocyst contained 2 sporozoites. Ultrastructurally, the sporocyst wall consisted of a dense inner layer 115 nm thick, transversely striated, regularly intercalated by thin grooves with electron-lucent spaces, and separated from the outer layer by a thin, light (electron-lucent) space. The outer layer was multilamellated and consisted of parallel dense bands alternating with light spaces. These lamellae formed filamentous extensions of the wall. The dehiscence suture, a characteristic feature of the genus, was present in the sporocysts. No external clinical signs were observed in the host fish. Parasites observed in the liver tissue were often enveloped in a yellowish-brown matrix, generally known as 'yellow bodies'. Sometimes sporocysts were observed in direct contact with the liver cells. Parasites in degeneration and aggregations of amylopectin granules were frequently observed surrounded by host inflammatory cells. In severe infections, we observed large agglomerations of oocysts encapsulated by layers of concentrically arranged connective tissue forming large granulomas, which caused significant replacement of the host liver parenchyma by the parasite. 相似文献
945.
Carolina V.M. Azevedo Alexandre A.L. Menezes Lúcio F.S. Moreira Nelson Marques 《Biological Rhythm Research》2013,44(5):563-571
One family group of common marmoset (Callithrix jacchus) was observed in captivity under natural environmental conditions to describe the circadian pattern of grooming behavior during the pregnancy of the reproductive female. The animals were observed by focal sampling, from the beginning to the end of animal's active phase, during two non-consecutive days per week, from August to November 1996. The duration of self-grooming and social grooming behavior of each animal were totalled each hour. The time series obtained were analyzed by Cluster Analysis and by Sin gle Cosinor Analysis. The daily patterns of grooming behavior during pregnancy were divided by Cluster Analysis into two stages, one corresponding to the second half of the third month of pregnancy, and the other from the last half of the third month to the last week before parturition. The confidence intervals of acrophases overlapped in all stages. The acrophases values of the first stage occurred between 10:09 h and 11:00 h, and on the second stage between 8:51 h and 11:13 h. The daily pattern of grooming behavior of adult male and female showed a trend to increase in the first hours of the active phase. This trend to advance grooming behavior during the second stage of pregnancy may be due to an effect of the coming parturition itself or to seasonal influences. 相似文献
946.
Daniel W. C. L. Santos Ana Carolina B. Padovan Analy S. A. Melo Sarah S. Gonçalves Viviane R. Azevedo Marilia M. Ogawa Tainá Veras Sandes Freitas Arnaldo L. Colombo 《Mycopathologia》2013,175(5-6):445-454
Subcutaneous infections caused by melanised fungi have been increasingly reported among transplant patients, and these infections have the potential for blood and visceral dissemination. Some moulds, such as Mycelia sterilia, cannot grow and sporulate on different media, making their identification impossible by conventional methods. The fast and accurate identification of melanised fungi at the species level is important because species may have tropism to different organs and different susceptibilities to antifungal agents. Molecular tools have been reported to be helpful for the species identification of non-sporulating moulds. Our goal was to identify the species of M. sterilia isolates obtained from clinical samples of transplant patients using sequences of ITS and the D1/D2 regions of rDNA. Clinical samples were obtained from eight kidney transplant recipients who developed subcutaneous fungal infections. The diagnosis was confirmed by histopathology and conventional culture. Histopathology showed septated, melanised hyphae, and the cultures identified non-sporulating fungi. Therefore, the DNA from the M. sterilia isolates was subjected to PCR amplification and sequencing of the ITS and D1/D2 regions. Genus/species identification was obtained by comparison with gene banks. We obtained the following identifications: Alternaria sp. (2), Cochliobolus lunatus/Curvularia lunata (2), Cochliobolus hawaiiensis/Bipolaris hawaiiensis (1), Ochroconis sp. (1), Medicocopsis romeroi/Pyrenochaeta romeroi (1) and Nigrograna mackinnonii/Pyrenochaeta mackinnonii (1). 相似文献
947.
Fabiana Lopes Rocha André Luiz Rodrigues Roque Juliane Saab de Lima Carolina Carvalho Cheida Frederico Gemesio Lemos Fernanda Cavalcanti de Azevedo Ricardo Corassa Arrais Daniele Bilac Heitor Miraglia Herrera Guilherme Mour?o Ana Maria Jansen 《PloS one》2013,8(7)
Little is known on the role played by Neotropical wild carnivores in the Trypanosoma cruzi transmission cycles. We investigated T. cruzi infection in wild carnivores from three sites in Brazil through parasitological and serological tests. The seven carnivore species examined were infected by T. cruzi, but high parasitemias detectable by hemoculture were found only in two Procyonidae species. Genotyping by Mini-exon gene, PCR-RFLP (1f8/Akw21I) and kDNA genomic targets revealed that the raccoon (Procyon cancrivorus) harbored TcI and the coatis (Nasua nasua) harbored TcI, TcII, TcIII-IV and Trypanosoma rangeli, in single and mixed infections, besides four T. cruzi isolates that displayed odd band patterns in the Mini-exon assay. These findings corroborate the coati can be a bioaccumulator of T. cruzi Discrete Typing Units (DTU) and may act as a transmission hub, a connection point joining sylvatic transmission cycles within terrestrial and arboreal mammals and vectors. Also, the odd band patterns observed in coatis’ isolates reinforce that T. cruzi diversity might be much higher than currently acknowledged. Additionally, we assembled our data with T. cruzi infection on Neotropical carnivores’ literature records to provide a comprehensive analysis of the infection patterns among distinct carnivore species, especially considering their ecological traits and phylogeny. Altogether, fifteen Neotropical carnivore species were found naturally infected by T. cruzi. Species diet was associated with T. cruzi infection rates, supporting the hypothesis that predator-prey links are important mechanisms for T. cruzi maintenance and dispersion in the wild. Distinct T. cruzi infection patterns across carnivore species and study sites were notable. Musteloidea species consistently exhibit high parasitemias in different studies which indicate their high infectivity potential. Mesocarnivores that feed on both invertebrates and mammals, including the coati, a host that can be bioaccumulator of T. cruzi DTU’s, seem to take place at the top of the T. cruzi transmission chain. 相似文献
948.
Debmalya Barh Neha Barve Krishnakant Gupta Sudha Chandra Neha Jain Sandeep Tiwari Nidia Leon-Sicairos Adrian Canizalez-Roman Anderson Rodrigues dos Santos Syed Shah Hassan Síntia Almeida Rommel Thiago Jucá Ramos Vinicius Augusto Carvalho de Abreu Adriana Ribeiro Carneiro Siomar de Castro Soares Thiago Luiz de Paula Castro Anderson Miyoshi Artur Silva Anil Kumar Amarendra Narayan Misra Kenneth Blum Eric R. Braverman Vasco Azevedo 《PloS one》2013,8(1)
Vibrio cholerae is the causal organism of the cholera epidemic, which is mostly prevalent in developing and underdeveloped countries. However, incidences of cholera in developed countries are also alarming. Because of the emergence of new drug-resistant strains, even though several generic drugs and vaccines have been developed over time, Vibrio infections remain a global health problem that appeals for the development of novel drugs and vaccines against the pathogen. Here, applying comparative proteomic and reverse vaccinology approaches to the exoproteome and secretome of the pathogen, we have identified three candidate targets (ompU, uppP and yajC) for most of the pathogenic Vibrio strains. Two targets (uppP and yajC) are novel to Vibrio, and two targets (uppP and ompU) can be used to develop both drugs and vaccines (dual targets) against broad spectrum Vibrio serotypes. Using our novel computational approach, we have identified three peptide vaccine candidates that have high potential to induce both B- and T-cell-mediated immune responses from our identified two dual targets. These two targets were modeled and subjected to virtual screening against natural compounds derived from Piper betel. Seven compounds were identified first time from Piper betel to be highly effective to render the function of these targets to identify them as emerging potential drugs against Vibrio. Our preliminary validation suggests that these identified peptide vaccines and betel compounds are highly effective against Vibrio cholerae. Currently we are exhaustively validating these targets, candidate peptide vaccines, and betel derived lead compounds against a number of Vibrio species. 相似文献
949.
Marcos Paulo Gomes Pinheiro José Hilário Tavares Silva Katrine Bezerra Cavalcanti Paulo Roberto Medeiros de Azevedo Maria de Fátima Freire de Melo Ximenes 《Journal of vector ecology》2013,38(2):307-316
Phlebotomine vectors transmit parasites and can cause visceral leishmaniasis (VL) or cutaneous leishmaniasis (TL). Phlebotomine females are hematophagous but need to ingest carbohydrates, possibly promoting the development of protozoan parasites in their digestive tract. The present study evaluated the species composition and abundance across several habitats in a metropolitan landscape, as well as associations among phlebotomines, plants, and local climatic parameters. Three consecutive monthly collections were carried out in an Atlantic Forest fragment, using CDC light traps in peridomestic areas and cashew, coconut, and mango tree. plantations. Eight species of phlebotomine were captured: Evandromyia evandroi, Lutzomyia longipalpis, Psathyromyia shannoni, Sciopemyia sordellii, Evandromyia walkeri, Psychodopygus wellcomei, Nyssomyia whitmani, and Nyssomyia intermedia, primarily from the forest environment. L. longipalpis was confirmed as a species adapted to anthropic environments, while P. wellcomei was shown to be predominately forest‐dwelling. Phlebotomines exhibited diversified food consumption patterns in relation to carbohydrate sources. They fed on both native and exotic species of arboreal and shrubby vegetables and gramineous plants. 相似文献
950.