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101.
Therapeutic concentrations of varenicline in the presence of nicotine increase action potential firing in human adrenal chromaffin cells 下载免费PDF全文
102.
Gonzalez-Martinez Alejandro Rodriguez-Sanchez Alejandro Rivadeneyra María Angustias Rivadeneyra Almudena Martin-Ramos Daniel Vahala Riku Gonzalez-Lopez Jesús 《Applied microbiology and biotechnology》2017,101(2):817-829
Applied Microbiology and Biotechnology - A bench-scale granular autotrophic nitrogen removal bioreactor (completely autotrophic nitrogen removal over nitrite (CANON) system) used for the treatment... 相似文献
103.
Nikolay Vassilev Maria Vassileva Rosario Azcon Almudena Medina 《Biotechnology letters》2001,23(2):149-151
Four times higher nodule number was observed when Glomus deserticola (an arbuscular mycorrhizal fungus) was introduced into a soil-plant system as compared to the control inoculated only with Rhizobium trifoli. This symbiotic parameter was further enhanced by Yarowia lipolytica together with an increase in root mycorrhizal infection of about 14%. Soil inoculation with co-encapsulated R. trifoli and Y. lipolytica provoked a 10-fold increase in root nodulation and led to 55% mycorrhization of the test plant. 相似文献
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105.
Almudena Ferrández-Ayela Rosa Micol-Ponce Ana Belén Sánchez-García María Magdalena Alonso-Peral José Luis Micol María Rosa Ponce 《PloS one》2013,8(11)
N-α-terminal acetylation is one of the most common, but least understood modifications of eukaryotic proteins. Although a high degree of conservation exists between the N-α-terminal acetylomes of plants and animals, very little information is available on this modification in plants. In yeast and humans, N-α-acetyltransferase complexes include a single catalytic subunit and one or two auxiliary subunits. Here, we report the positional cloning of TRANSCURVATA2 (TCU2), which encodes the auxiliary subunit of the NatB N-α-acetyltransferase complex in Arabidopsis. The phenotypes of loss-of-function tcu2 alleles indicate that NatB complex activity is required for flowering time regulation and for leaf, inflorescence, flower, fruit and embryonic development. In double mutants, tcu2 alleles synergistically interact with alleles of ARGONAUTE10, which encodes a component of the microRNA machinery. In summary, NatB-mediated N-α-terminal acetylation of proteins is pleiotropically required for Arabidopsis development and seems to be functionally related to the microRNA pathway. 相似文献
106.
Epistasis and the temporal change in the additive variance-covariance matrix induced by drift 总被引:3,自引:0,他引:3
López-Fanjul C Fernández A Toro MA 《Evolution; international journal of organic evolution》2004,58(8):1655-1663
The effect of population bottlenecks on the components of the genetic covariance generated by two neutral independent epistatic loci has been studied theoretically (additive, covA; dominance, covD; additive-by-additive, covAA; additive-by-dominance, covAD; and dominance-by-dominance, covDD). The additive-by-additive model and a more general model covering all possible types of marginal gene action at the single-locus level (additive/dominance epistatic model) were considered. The covariance components in an infinitely large panmictic population (ancestral components) were compared with their expected values at equilibrium over replicates randomly derived from the base population, after t consecutive bottlenecks of equal size N (derived components). Formulae were obtained in terms of the allele frequencies and effects at each locus, the corresponding epistatic effects and the inbreeding coefficient Ft. These expressions show that the contribution of nonadditive loci to the derived additive covariance (covAt) does not linearly decrease with inbreeding, as in the pure additive case, and may initially increase or even change sign in specific situations. Numerical examples were also analyzed, restricted for simplicity to the case of all covariance components being positive. For additive-by-additive epistasis, the condition covAt > covA only holds for high frequencies of the allele decreasing the metric traits at each locus (negative allele) if epistasis is weak, or for intermediate allele frequencies if it is strong. For the additive/dominance epistatic model, however, covAt > covA applies for low frequencies of the negative alleles at one or both loci and mild epistasis, but this result can be progressively extended to intermediate frequencies as epistasis becomes stronger. Without epistasis the same qualitative results were found, indicating that marginal dominance induced by epistasis can be considered as the primary cause of an increase of the additive covariance after bottlenecks. For all models, the magnitude of the ratio covAt/covA was inversely related to N and t. 相似文献
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Almudena Martínez‐Monzón Hugues‐Alexandre Blain Gloria Cuenca‐Bescós Miguel Ángel Rodríguez 《Ecography》2018,41(8):1307-1318
In recent years several studies have been carried out to test the validity of Bergmann's rule for amphibians, and have generated varying results. Due to the lack of agreement on this topic, here we examine the relationship between climate and body size for one anuran species (Bufo calamita, commonly known as the natterjack toad) with a new methodological approach that uses the fossil record as the data source. We analysed bones from two archaeo‐paleontological sites located close to each other in the Sierra de Atapuerca (Burgos, Spain) that together encompass more than one million years from Early to Late Pleistocene. We used ordinary least squares (OLS) simple regression models to integrate body size and palaeoclimatic data (temperature and precipitation) and describe the relationship between the amphibian's body size and climate along the entire temporal gradient. We found the body size of B. calamita to be negatively related to the mean annual temperature and the mean temperature of the coldest month, and positively related to December‐to‐February precipitation. The climatic influence was stronger in females, which were smaller than males in most cases, and therefore an inverse sexual size dimorphism pattern was found. Juvenile individuals or the limited sexual size dimorphism of this species may be causes of this unusual pattern. Bufo calamita populations showed a clear Bergmann cline during the Pleistocene period, and winter stands out as the most influential season. Although this new methodology can only be used to describe patterns, we discuss several mechanisms that could explain our results. We propose that starvation resistance and delayed maturation are the main causes for this increase in size in periods with cooler winters, and a fecundity‐related hypothesis to explain why climate has a greater influence on female body size. 相似文献
109.
Rocio Sanchez-Alcudia Maria Garcia-Hoyos Miguel Angel Lopez-Martinez Noelia Sanchez-Bolivar Olga Zurita Ascension Gimenez Cristina Villaverde Luciana Rodrigues-Jacy da Silva Marta Corton Raquel Perez-Carro Simona Torriano Vasiliki Kalatzis Carlo Rivolta Almudena Avila-Fernandez Isabel Lorda Maria J. Trujillo-Tiebas Blanca Garcia-Sandoval Maria Isabel Lopez-Molina Fiona Blanco-Kelly Rosa Riveiro-Alvarez Carmen Ayuso 《PloS one》2016,11(4)
Choroideremia (CHM) is a rare X-linked disease leading to progressive retinal degeneration resulting in blindness. The disorder is caused by mutations in the CHM gene encoding REP-1 protein, an essential component of the Rab geranylgeranyltransferase (GGTase) complex. In the present study, we evaluated a multi-technique analysis algorithm to describe the mutational spectrum identified in a large cohort of cases and further correlate CHM variants with phenotypic characteristics and biochemical defects of choroideremia patients. Molecular genetic testing led to the characterization of 36 out of 45 unrelated CHM families (80%), allowing the clinical reclassification of four CHM families. Haplotype reconstruction showed independent origins for the recurrent p.Arg293* and p.Lys178Argfs*5 mutations, suggesting the presence of hotspots in CHM, as well as the identification of two different unrelated events involving exon 9 deletion. No certain genotype-phenotype correlation could be established. Furthermore, all the patients´ fibroblasts analyzed presented significantly increased levels of unprenylated Rabs proteins compared to control cells; however, this was not related to the genotype. This research demonstrates the major potential of the algorithm proposed for diagnosis. Our data enhance the importance of establish a differential diagnosis with other retinal dystrophies, supporting the idea of an underestimated prevalence of choroideremia. Moreover, they suggested that the severity of the disorder cannot be exclusively explained by the genotype. 相似文献
110.
Fiona Blanco-Kelly María García Hoyos Miguel Angel Lopez Martinez Maria Isabel Lopez-Molina Rosa Riveiro-Alvarez Patricia Fernandez-San Jose Almudena Avila-Fernandez Marta Corton Jose M. Millan Blanca García Sandoval Carmen Ayuso 《PloS one》2016,11(2)