RESUMEN
The white-clawed crayfish (Austropotamobius italicus), a cornerstone of Spain's aquatic ecosystems, was once widely distributed throughout much of the country. Unfortunately, its populations have suffered very strong declines over the last 40 years due to the spread of introduced species (red swamp and signal crayfishes), diseases, habitat loss and other anthropogenic impacts. The present work examines the genetic variation in 23 Spanish and four Italian populations of white-clawed crayfish via the analysis of microsatellite loci. The data show genetic variation in the Spanish populations to be affected by drastic and successive bottlenecks. Notwithstanding, the diversity of these Spanish populations in terms of observed heterozygosity is similar to or even higher than that recorded for other European populations studied using these same markers. North-central Spanish populations are clearly differentiated from the country's remaining populations; they should be considered distinct management units. Processes occurred in historical and recent times, such as genetic drift and translocations, contribute greatly to this genetic structure. These data provide useful information for conservation of this species, since the preservation of its population structure and genetic variability should be goals for management decisions.
Asunto(s)
Astacoidea/genética , Especies en Peligro de Extinción , Variación Genética , Filogenia , Animales , Conservación de los Recursos Naturales/métodos , Genética de Población , Italia , Repeticiones de Microsatélite/genética , Filogeografía , Dinámica Poblacional , EspañaRESUMEN
Spanish freshwater ecosystems are suffering great modification and some macroinvertebrates like Austropotamobius italicus, the white-clawed crayfish, are threatened. This species was once widely distributed in Spain, but its populations have shown a very strong decline over the last thirty years, due to different factors. Three Spanish populations of this crayfish--from different scenarios--were analysed with nuclear (microsatellites) and mitochondrial markers (COI and 16S rDNA). Data analyses reveal the existence of four haplotypes at mitochondrial level and polymorphism for four microsatellite loci. Despite this genetic variability, bottlenecks were detected in the two natural Spanish populations tested. In addition, the distribution of the mitochondrial haplotypes and SSR alleles show a similar geographic pattern and the genetic differentiation between these samples is mainly due to genetic drift. Given the current risk status of the species across its range, this diversity offers some hope for the species from a management point of view.
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Astacoidea/clasificación , Astacoidea/genética , Alelos , Animales , Astacoidea/fisiología , Ecosistema , Complejo IV de Transporte de Electrones/metabolismo , Variación Genética , Geografía , Haplotipos , Heterocigoto , Repeticiones de Microsatélite/genética , Mitocondrias/metabolismo , Modelos Genéticos , Dinámica Poblacional , ARN Ribosómico 16S/metabolismo , EspañaRESUMEN
Spain is the leading producer of olives and olive oil. Ninety-five percent of world production originate from Spain and other regions of the Mediterranean Basin. However, these olive-growing countries face a major problem, the harmful fly Bactrocera oleae, the main pest of olive crops. To improve its control, one of the challenges is the further knowledge of the species and populations dynamics in this area. A phylogeographic work is necessary to further characterise the levels and distribution patterns of genetic diversity of the Spanish populations and their genetic relationships with other Mediterranean populations. A 1151 bp fragment of the mitochondrial cytochrome oxidase subunit I (COI) gene has been analysed in over 250 specimens of the six main Mediterranean countries via sequencing. Genetic diversity parameters were high; 51 new haplotypes have been identified showing a geographical pattern across the Mediterranean area. The data revealed that olive fruit fly populations have been long time established in the Mediterranean Basin with two genetic groups. Gene flow seems to be the main process in shaping this genetic structure as well as fly's colonisation routes that have paralleled those of the olive tree.
RESUMEN
The olive fruit fly (olf) Bactrocera oleae is the most damaging olive pest. The intensive use of organophosphates (OPs) to control it, led to an increase in resistance in field populations. This study assesses the presence and distribution of three mutations at the ace gene related to target site insensitivity to OPs in Spain. Samples from other Mediterranean countries were included as external references. Resistance-conferring alleles (from exons IV and VII of the ace gene) reached almost an 80% frequency in olf Spanish populations. In total, 62% of them were homozygous (RR/RR), this being more common in eastern mainland Spain. High frequencies of RR/RR individuals were also found in North Mediterranean samples. Conversely, in Tunisia, only sensitive alleles were detected. Finally, the exon X mutation ∆Q3 had an extremely low frequency in all samples. The high frequency of genotype RR/RR in Spain indicates high fitness in an agroecosystem treated with pesticides, in contrast to ∆Q3. At exon IV all flies carried the same haplotype for the allele conferring resistance. The sequence analysis at this exon suggests a unique origin and fast expansion of the resistant allele. These results provide evidence that OPs appropriate use is needed and prompt the search for alternative methods for olf pest control.
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INTRODUCTION: Malnutrition is a common complication in cancer patients and can negatively affect the outcome of treatments. This study aimed to reach a consensus on nutritional needs and optimize nutritional care in the management of cancer patients at a national level. METHODS: A qualitative, multicenter, two-round Delphi study involving 52 specialists with experience in nutritional support in cancer patients was conducted. RESULTS: Regarding the presence of malnutrition, 57.7% of the participants stated that < 30% of the patients had malnutrition at the time of diagnosis, 40.4% considered that 31-50% had malnutrition during cancer treatment, and 26.9% that > 50% at the end of the treatment. Forty percent of participants believed that the main objective of nutritional treatment was to improve quality of life and 34.6% to improve tolerability and adherence to chemotherapy. The quality nutritional care provided at their centers was rated as medium-low by 67.3%. Enteral and parenteral nutrition was administered to less than 10% and less than 5% of patients in 40.4 and 76.9% of cases, respectively. In relation to nutritional screening at the time of diagnosis, 62.9% of participants considered than screening to assess the risk of malnutrition was performed in < 30% of patients. CONCLUSIONS: There is an important variability in the management of cancer patient nutrition, which is associated with the absence of a national consensus on nutritional support in this field. Given the incidence of nutritional disorders in cancer patients, a specialist in clinical nutrition (regardless of his/her specialty) should be integrated into the strategic cancer plan.
Asunto(s)
Neoplasias/terapia , Apoyo Nutricional , Adulto , Técnica Delphi , Femenino , Humanos , Masculino , Desnutrición/terapia , Persona de Mediana Edad , Nutrición ParenteralRESUMEN
Based on the multi-foil technique, a multichannel soft x-ray diagnostic for electron temperature measurements has been recently implemented in the TJ-II stellarator. The diagnostic system is composed by four photodiodes arrays with beryllium filters of different thickness. An in-vacuum amplifier board is coupled to each array, aiming at preventing induced noise currents. The Thomson scattering and the vacuum ultraviolet survey diagnostics are used for assessing plasma profiles and composition, being the analysis carried out with the radiation code IONEQ. The electron temperature is determined through the different signal-pair ratios with temporal and spatial resolution. The design and preliminary results from the diagnostic are presented.
RESUMEN
The core electron temperature (T(e0)) of neutral beam heated plasmas is determined in TJ-II stellarator by using soft x ray detectors with beryllium filters of different thickness, based on the method known as the foil absorption technique. T(e0) estimations are done with the impurity code IONEQ, making use of complementary information from the TJ-II soft x ray tomography and the VUV survey diagnostics. When considering the actual electron density and temperature profile shapes, an acceptable agreement is found with Thomson scattering measurements for 8 different magnetic configurations. The impact of the use of both neutral beam injectors on the T(e0) measurements is addressed. Also, the behaviour of T(e0) during spontaneous profile transitions is presented.
RESUMEN
The design and preliminary results from a prototype of a multifilter based electron temperature diagnostic for the TJ-II stellarator are presented. The diagnostic consists of four photodiodes with filters of different thicknesses to determine the electron temperature in a wide variety of plasma compositions, thanks to the set of six different signal-pairs ratios available. The impurity transport code IONEQ, the TJ-II soft x-ray tomography, and the VUV survey diagnostics give the necessary information to assess the proposed diagnostic reliability. In parallel, a vacuum-compatible multichannel electronic board has been designed for a future linear array to determine electron temperature profiles in high-density plasmas.
RESUMEN
Fruit flies (Diptera: Tephritidae) are a species-rich and economically important group. The phylogenetic relationships among the many taxa are still to be fully resolved and the monophyly of several groups is still to be confirmed. This paper reports a study of the phylogenetic relationships among 23 economically important tephritid species (representing several major lineages of the family) which examines the sequence of a region of mitochondrial DNA encompassing the cytb, tRNA(Ser) and ND1 genes. Substitutions characteristic of particular taxa were found that could help classify members of the family at any developmental stage. The trees obtained by the maximum parsimony, neighbour joining and maximum likelihood methods were generally compatible with present morphological classification patterns. However, the data reveal some characteristics of the phylogenetic relationships of this family that do not agree with present classifications. The results support the probable non-monophyletic nature of the subfamily Trypetinae and suggest that Bactrocera cucurbitae (Coquillet) is more closely related to the genus Dacus than to other species of Bactrocera.
Asunto(s)
ADN Mitocondrial/genética , Filogenia , Tephritidae/clasificación , Tephritidae/genética , Animales , Citocromos b/genética , Cartilla de ADN/química , Femenino , Masculino , Datos de Secuencia Molecular , NADH Deshidrogenasa/genética , ARN de Transferencia/genética , Análisis de Secuencia de ADN/veterinaria , Análisis de Secuencia de Proteína/veterinariaRESUMEN
Random amplified polymorphic DNA (RAPD) markers were used to estimate the population structure and phylogenetic relationships among the eight species of the genus Barbus that inhabit the Iberian Peninsula. Ten random oligodecamers were used to amplify DNA from 232 fish sampled from 15 populations. A total of 270 markers were detected that revealed low levels of genetic variability. The conclusions of cluster analysis indicate two main branches and three well-differentiated groups: north-eastern, Mediterranean and Atlantic. This clustering mainly reflects the evolutionary history of the genus, which is closely related to the paleogeography of the Iberian Peninsula. The contribution and application of these results to the conservation of the species, to their taxonomic status and to the process of colonization of the Iberian Peninsula by the genus Barbus are discussed.
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Cyprinidae/clasificación , Animales , Cyprinidae/genética , Marcadores Genéticos , Filogenia , Técnica del ADN Polimorfo Amplificado Aleatorio , EspañaRESUMEN
Nucleotide sequence fragments of the mitochondrial DNA gene encoding cytochrome b were examined in 26 individuals belonging to the seven species of Barbus endemic to the Iberian Peninsula: Barbus haasi, B. bocagei, B. graellsii, B. sclateri, B. comiza, B. guiraonis, and B. microcephalus. Six of the seven currently recognized species can be distinguished on the basis of their cytochrome b nucleotide sequences. Sequence divergence estimates for Spanish species of Barbus (0-6.5%) are, in general, low in comparison to those reported for other fish species, and hybrid individuals were found. All of these observations suggest a recent radiation. The inferred phylogenetic tree has two main clades, one including B. graellsii, B. guiraonis, and B. microcephalus, and the other the remaining species groups.
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Cyprinidae/genética , Grupo Citocromo b/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cyprinidae/clasificación , Grupo Citocromo b/clasificación , ADN Mitocondrial , Datos de Secuencia Molecular , Filogenia , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie , Factores de TiempoRESUMEN
We have collected several hundred Drosophila melanogaster flies (near Davis, California), isolated them individually, without anesthesia, at the collecting site, and estimated the fitness components of the wild-caught females under different environmental conditions. The fitness parameters measured are fecundity, oviposition rate, and productivity (egg-to-adult viability, development rate, and number of progeny). The environmental variables are two temperatures (22 degrees C and 28 degrees C) and two densities ('scant' and 'crowded'). After the fitness measurements are completed for each individual female, its genotype is determined at four loci encoding enzymes: GPDH and ADH, located on chromosome II; and PGM and EST-C, located on chromosome III. Density has a large significant effect on productivity; temperature has significant effects on fecundity, oviposition rate, and development rate. The experiments show that allozyme polymorphisms are associated with selection effects. Fitness differences between allozyme genotypes occur for all fitness components, except oviposition rate. But which genotype is superior depends on the environmental conditions; heterozygotes exhibit higher fitness than homozygotes in a number of cases, but inferior in others. A unique feature of the present experiments is that the experimental flies are wild-caught females rather than laboratory-bred individuals.
Asunto(s)
Alcohol Deshidrogenasa/genética , Proteínas de Drosophila , Drosophila melanogaster/genética , Esterasas/genética , Glicerolfosfato Deshidrogenasa/genética , Fosfoglucomutasa/genética , Animales , Drosophila melanogaster/anatomía & histología , Femenino , Fertilidad/genética , Variación Genética , Homocigoto , Masculino , Oviposición , Linaje , Polimorfismo Genético , TemperaturaRESUMEN
Ceratitis capitata is one of the most important pest species in the tropical and temperate regions of the world, however, genetic knowledge of this species is still very limited. In the present study, we have attempted for the first time an analysis of the genetic variability in seven natural populations of C. capitata by means of abundant soluble proteins, combining high resolution techniques such as polyacrylamide gel electrophoresis and silver staining methods. A total of 66 polypeptides have been analyzed. The results show the existence of a decreasing trend in the 'levels' of polymorphism from the southern areas to the northern that is correlated with the latitude of the sampling areas, most probably due to the colonization process of the Iberian Peninsula. On the other hand, and with relation to the 'pattern' of the variability, a geographic differentiation (not strictly latitudinal) is detected when an UPGMA clustering method was applied to the data. Moreover, principal component anaysis has revealed that a part of this differentiation could be explained in relation with environmental factors such as annual rainfall and minimum temperature in winter months. This is suggesting that selection (added to the historical process) could be playing an important role in the process of geographic differentiation, 'shaping' the pattern of that variability. No host-related differentiation has been observed in these samples.
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Male mating success is an important fitness component in Drosophila. The seminal fluid conveyed with the sperm inhibits the proclivity of the female to remate and reduces her fitness. Nevertheless, females may remate before they have exhausted the sperm from the first male and consequently use sperm from both males. We have studied concurrent multiple paternity (CMP) in two Drosophila melanogaster populations, from an apple orchard and a vineyard just after harvest. CMP is high in both populations, somewhat greater than 50%; but it is not significantly higher in the vineyard, where the population density is much greater than in the orchard. Population density had been thought to be an important determinant of CMP incidence. We have used four gene loci coding for enzymes as independent markers for detecting CMP.