Search results for "Ciencias Biológicas"
showing 10 items of 794 documents
Breizacanthus aznari sp. n. (Acanthocephala: Arhythmacanthidae) from the banded cusk-eel Raneya brasiliensis (Ophidiiformes: Ophidiidae) from the Pat…
2012
Breizacanthus aznari sp. n. is described from the banded cusk-eel Raneya brasiliensis (Kaup) (Ophidiiformes: Ophidiidae) from the Patagonian coast in Argentina. Breizacanthus Golvan, 1969 is currently composed of five species (including the new species) and is characterised by the absence of trunk spines, a short cylindrical proboscis with two types of hooks and lemnisci longer than the proboscis receptacle. Breizacanthus aznari is clearly distinguished from B. chabaudi Golvan, 1969 by having 12 longitudinal rows of hooks on the proboscis, instead of 16-18. The new species resembles B. golvani Gaevskaya et Shukhgalter, 1984, B. irenae Golvan, 1969, and B. ligur Paggi, Orecchia et Della Seta…
Parasites in Stranded Cetaceans of Patagonia
2008
There is an increasing interest in parasites of marine mammals of Argentina. Here, we examined several poorly known cetaceans, i.e., 2 spectacled porpoises and 1 Burmeister's porpoise (Phocoenidae), and 1 Gray's beaked whale and 1 Cuvier's beaked whale (Ziphidae); we also updated the parasite information for 1 sperm whale (Physeteridae). These hosts strand only occasionally. We found Anisakis simplex s.l. in 2 spectacled porpoises and the Burmeister's porpoise, and recorded its distribution among the stomach chambers. Anisakis physeteris infected the sperm whale; Corynosoma cetaceum occurred in the duodenal ampulla of the Burmeister's porpoise; Corynosoma australe was found in the posterior…
Population dynamics of Antarctophthirus microchir (Anoplura: Echinophthiriidae) in pups from South American sea lion, Otaria flavescens, in Northern …
2009
We analysed population dynamics of the louse Antarctophthirus microchir in pups of the South American sea lion, Otaria flavescens, at the Punta León rookery (Argentina) over a period of 2 years. A total of 136 pups were aged and marked at the beginning of the lactation period ashore, then sampled for lice at different times within 30 days. Sampling was restricted to the chest and belly, two sites where lice were especially abundant. This concentration on ventral areas might protect lice from thermal stress in the austral summer. Infestation patterns in pups ≤3 days old suggested that the potential for transmission increased from first nymphs to adults. Population trends of each instar with …
Signals of demographic expansion in Drosophila virilis
2008
Background. The pattern of genetic variation within and among populations of a species is strongly affected by its phylogeographic history. Analyses based on putatively neutral markers provide data from which past events, such as population expansions and colonizations, can be inferred. Drosophila virilis is a cosmopolitan species belonging to the virilis group, where divergence times between different phylads go back to the early Miocene. We analysed mitochondrial DNA sequence variation among 35 Drosophila virilis strains covering the species' range in order to detect demographic events that could be used to understand the present characteristics of the species, as well as its differences …
2,3,9- and 2,3,11-Trisubstituted tetrahydroprotoberberines as D2 dopaminergic ligands
2013
Dopamine-mediated neurotransmission plays an important role in relevant psychiatric and neurological disorders. Nowadays, there is an enormous interest in the development of new dopamine receptors (DR) acting drugs as potential new targets for the treatment of schizophrenia or Parkinson's disease. Previous studies have revealed that isoquinoline compounds such as tetrahydroisoquinolines (THIQs) and tetrahydroprotoberberines (THPBs) can behave as selective D-2 dopaminergic alkaloids since they share structural similarities with dopamine. In the present study we have synthesized eleven 2,3,9- and 2,3,11-trisubstituted THPB compounds (six of them are described for the first time) and evaluated…
Mechanisms of DNA damage by photoexcited 9-methyl-β-carbolines
2013
It has been well documented that β-carboline alkaloids, particularly the 9-methyl derivatives, are efficient photosensitizers. However, structure–activity relationships are missing and the photochemical mechanisms involved in the DNA photodamage still remain unknown. In the present work, we examined the capability of three 9-methyl-β-carbolines (9-methyl-norharmane, 9-methyl-harmane and 9-methylharmine) to induce DNA damage upon UVA excitation at physiological pH. The type and extent of the damage was analyzed together with the photophysical and binding properties of the β-carboline derivatives investigated. The results indicate that even at neutral pH most of the DNA damage is generated fr…
Oenothera laciniata Hill (Onagraceae) en la Comunidad Valenciana
2012
Se da a conocer la presencia de la especie naturalizada Oenothera laciniata, como novedad para la flora de la Comunidad Valenciana (E de España); a la vez que constituye su segunda indicación reciente para la Península Ibérica. Se trata de una planta alóctona, nativa de la mitad oriental de Norteamérica, que debe ser considerada como potencial invasora de los ecosistemas mediterráneos. Se ofrecen datos morfológicos para facilitar la identificación de la especie y la futura detección de nuevas poblaciones. Además, se aporta una clave de identificación de las especies valencianas del género. Oenothera laciniata is reported for the first time in the Valencian Community (E of Spain), a report t…
Phelipanche lainzii, nueva Orobáncacea para la península Ibérica
2012
[ES] Se describe una nueva especie ibérica perteneciente al género Phelipanche Pomel (Orobanchaceae): Ph. lainzii, sp. nov., hallada en el noreste de la provincia de Albacete, cerca de la provincia de Valencia (E de España). Entre otras características, presenta por lo general tallo mediano a pequeño, inflorescencia densa, corola azul pálido de tubo estrecho, apenas infundibuliforme y no muy ensanchado en la garganta, con lóbulos del labio inferior no deflexos y cáliz con dientes subulados. Su morfología es parecida a Ph. mutelii (F.W. Schultz) Pomel, Ph. camphorosmae Carlón, G. Gómez, M. Laínz, Moreno Mor., Ó. Sánchez & Schneew. y Ph. nana (F.W. de Noë ex Rchb. fil.) Soják, por lo que se a…
Lotus tenuis x L. corniculatus interspecific hybridization as a means to breed bloat-safe pastures and gain insight into the genetic control of proan…
2014
Background: Proanthocyanidins (PAs) are secondary metabolites that strongly affect plant quality traits. The concentration and the structure of these metabolites influence the palatability and nutritional value of forage legumes. Hence, modulating PAs in the leaves of forage legumes is of paramount relevance for forage breeders worldwide. The lack of genetic variation in the leaf PA trait within the most important forage species and the difficulties in engineering this pathway via the ectopic expression of regulatory genes, prompted us to pursue alternative strategies to enhance this trait in forage legumes of agronomic interest. The Lotus genus includes forage species which accumulate PAs …
Salix breviserrata Flod., novedad para la flora palentina
2016
Hemos encontrado una pequeña población del sauce rastrero Salix breviserrata Flod., novedad para la provincia de Palencia. Esta localización representa el emplazamiento más meridional de la corología global de este taxon alpino, que alcanza el norte de la Península Ibérica. S. breviserrata está catalogado como Vulnerable en la Lista Roja de la flora vascular española, lo que afianza el ya conocido valor florístico del entorno del macizo de Valdecebollas (Palencia, España). We found a small formation of brushes and low scrubs willow dominated by Salix breviserrata Flod., new taxon for the province of Palencia. This location represents the southernmost of the global chorology of this alpine s…