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1.
Zaida Tárano & Emilio A. Herrera† 《Ethology : formerly Zeitschrift fur Tierpsychologie》2003,109(2):121-134
Female preferences for male call traits may affect male mating success and the evolution of exaggerated secondary sexual traits. We used phonotaxis experiments to examine female preferences in the frog Physalaemus enesefae in relation to variation in male call duration, dominant frequency, intercall interval and amplitude (dB SPL). Females preferred long calls, low and average dominant frequency calls, short intercall intervals and more intense calls. We compared the patterns of female preferences with those of acoustic variation among males to test the prediction that properties with low within‐male variation are associated with stabilizing or weakly directional female preferences, whereas properties with high within‐male variation are associated with directional preferences. Females had weakly directional preferences for the dominant frequency of the call and strongly directional preferences for call duration and call rate. We also determined whether the temporal relationship between calls influenced preferences based on the dominant frequency of the call. Preferences for low‐frequency over high‐frequency calls disappeared when calls partially overlapped. Females preferred the leading call regardless of its dominant frequency. We also investigated mating patterns in the field. There was size‐assortative mating, as male and female body sizes snout‐vent length (SVL) were positively correlated. In addition, differences in the frequency distributions of body length (SVL) between mated and unmated males approached significance; lower SVL classes were underrepresented among mated males. These patterns may reflect female preferences for lower dominant frequency calls, as there is a negative correlation between male mass and the dominant frequency of the call. 相似文献
2.
Patrick O'Donoghue Zaida Luthey-Schulten 《Microbiology and molecular biology reviews》2003,67(4):550-573
The aminoacyl-tRNA synthetases are one of the major protein components in the translation machinery. These essential proteins are found in all forms of life and are responsible for charging their cognate tRNAs with the correct amino acid. The evolution of the tRNA synthetases is of fundamental importance with respect to the nature of the biological cell and the transition from an RNA world to the modern world dominated by protein-enzymes. We present a structure-based phylogeny of the aminoacyl-tRNA synthetases. By using structural alignments of all of the aminoacyl-tRNA synthetases of known structure in combination with a new measure of structural homology, we have reconstructed the evolutionary history of these proteins. In order to derive unbiased statistics from the structural alignments, we introduce a multidimensional QR factorization which produces a nonredundant set of structures. Since protein structure is more highly conserved than protein sequence, this study has allowed us to glimpse the evolution of protein structure that predates the root of the universal phylogenetic tree. The extensive sequence-based phylogenetic analysis of the tRNA synthetases (Woese et al., Microbiol. Mol. Biol. Rev. 64:202-236, 2000) has further enabled us to reconstruct the complete evolutionary profile of these proteins and to make connections between major evolutionary events and the resulting changes in protein shape. We also discuss the effect of functional specificity on protein shape over the complex evolutionary course of the tRNA synthetases. 相似文献
3.
Ana B. Fagundo Rafael de la Torre Susana Jiménez-Murcia Zaida Agüera Antoni Pastor Felipe F. Casanueva Roser Granero Rosa Ba?os Cristina Botella Amparo del Pino-Gutierrez Jose M. Fernández-Real Jose C. Fernández-García Gema Frühbeck Javier Gómez-Ambrosi José M. Menchón Inés Moragrega Roser Rodríguez Salomé Tárrega Francisco J. Tinahones Fernando Fernández-Aranda 《PloS one》2013,8(6)
Animal studies point to an implication of the endocannabinoid system on executive functions. In humans, several studies have suggested an association between acute or chronic use of exogenous cannabinoids (Δ9-tetrahydrocannabinol) and executive impairments. However, to date, no published reports establish the relationship between endocannabinoids, as biomarkers of the cannabinoid neurotransmission system, and executive functioning in humans. The aim of the present study was to explore the association between circulating levels of plasma endocannabinoids N-arachidonoylethanolamine (AEA) and 2-Arachidonoylglycerol (2-AG) and executive functions (decision making, response inhibition and cognitive flexibility) in healthy subjects. One hundred and fifty seven subjects were included and assessed with the Wisconsin Card Sorting Test; Stroop Color and Word Test; and Iowa Gambling Task. All participants were female, aged between 18 and 60 years and spoke Spanish as their first language. Results showed a negative correlation between 2-AG and cognitive flexibility performance (r = −.37; p<.05). A positive correlation was found between AEA concentrations and both cognitive flexibility (r = .59; p<.05) and decision making performance (r = .23; P<.05). There was no significant correlation between either 2-AG (r = −.17) or AEA (r = −.08) concentrations and inhibition response. These results show, in humans, a relevant modulation of the endocannabinoid system on prefrontal-dependent cognitive functioning. The present study might have significant implications for the underlying executive alterations described in some psychiatric disorders currently associated with endocannabinoids deregulation (namely drug abuse/dependence, depression, obesity and eating disorders). Understanding the neurobiology of their dysexecutive profile might certainly contribute to the development of new treatments and pharmacological approaches. 相似文献
4.
Manoeli Lupatini Afnan Khalil Ahmad Suleiman Rodrigo Josemar Seminoti Jacques Zaida Inês Antoniolli Eiko Eurya Kuramae Flávio Anastácio de Oliveira Camargo Luiz Fernando Würdig Roesch 《PloS one》2013,8(10)
The Pampa biome is considered one of the main hotspots of the world’s biodiversity and it is estimated that half of its original vegetation was removed and converted to agricultural land and tree plantations. Although an increasing amount of knowledge is being assembled regarding the response of soil bacterial communities to land use change, to the associated plant community and to soil properties, our understanding about how these interactions affect the microbial community from the Brazilian Pampa is still poor and incomplete. In this study, we hypothesized that the same soil type from the same geographic region but under distinct land use present dissimilar soil bacterial communities. To test this hypothesis, we assessed the soil bacterial communities from four land-uses within the same soil type by 454-pyrosequencing of 16S rRNA gene and by soil microbial activity analyzes. We found that the same soil type under different land uses harbor similar (but not equal) bacterial communities and the differences were controlled by many microbial taxa. No differences regarding diversity and richness between natural areas and areas under anthropogenic disturbance were detected. However, the measures of microbial activity did not converge with the 16S rRNA data supporting the idea that the coupling between functioning and composition of bacterial communities is not necessarily correlated. 相似文献
5.
Zaida Araujo Francesca Giampietro María de los Angeles Bochichio Andrea Palacios Jenifer Dinis Jaime Isern Jacobus Henry de Waard Elsa Rada Rafael Borges Carlos Fernández de Larrea Angel Villasmil Magnolia Vanegas Jose Antonio Enciso-Moreno Manuel Alfonso Patarroyo 《Memórias do Instituto Oswaldo Cruz》2013,108(2):131-139
The goal of this study was to demonstrate the usefulness of an enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of pulmonary tuberculosis (PTB) and extrapulmonary TB (EPTB). This assay used 20 amino acid-long, non-overlapped synthetic peptides that spanned the complete Mycobacterium tuberculosis ESAT-6 and Ag85A sequences. The validation cohort consisted of 1,102 individuals who were grouped into the following five diagnostic groups: 455 patients with PTB, 60 patients with EPTB, 40 individuals with non-EPTB, 33 individuals with leprosy and 514 healthy controls. For the PTB group, two ESAT-6 peptides (12033 and 12034) had the highest sensitivity levels of 96.9% and 96.2%, respectively, and an Ag85A-peptide (29878) was the most specific (97.4%) in the PTB groups. For the EPTB group, two Ag85A peptides (11005 and 11006) were observed to have a sensitivity of 98.3% and an Ag85A-peptide (29878) was also the most specific (96.4%). When combinations of peptides were used, such as 12033 and 12034 or 11005 and 11006, 99.5% and 100% sensitivities in the PTB and EPTB groups were observed, respectively. In conclusion, for a cohort that consists entirely of individuals from Venezuela, a multi-antigen immunoassay using highly sensitive ESAT-6 and Ag85A peptides alone and in combination could be used to more rapidly diagnose PTB and EPTB infection. 相似文献
6.
7.
Juan L. Fuentes Volker A. R. Huss Zaida Montero Rafael Torronteras María Cuaresma Inés Garbayo Carlos Vílchez 《Journal of applied phycology》2016,28(6):3269-3279
The genus Coccomyxa comprises green microalgae, which can be found worldwide in remarkably versatile aquatic and terrestrial ecosystems including symbiotic associations with a number of different hosts. In this study, we describe a new species, Coccomyxa onubensis, based on 18S and ITS ribosomal DNA (rDNA) sequence data. Coccomyxa onubensis was isolated from acidic water, and its ability to adapt to a wide range of acidic and alkaline pH values and to high salinity was analyzed. The long-term adaptation capacity of the microalga to such extreme conditions was evaluated by performing continuous repeated batches at selected salt concentrations and pH values. Adapted cultures of C. onubensis were found to yield high biomass productivities from pH 2.5 to 9, with maximum yields at acidic pH between 2.5 and 4.5. Moreover, C. onubensis was also found to adapt to salinities as high as 0.5 M NaCl, reaching biomass productivities that were similar to those of control cultures. Ultrastructural analysis by transmission electron microscopy of C. onubensis cells adapted to high salinity showed a robust response to hyperosmotic shock. Thus, C. onubensis was found to be acidotolerant and halotolerant. High biomass productivity over a wide range of pH and salinities denotes C. onubensis as an interesting candidate for various biotechnological applications including outdoor biomass production. 相似文献
8.
Artificial endosperm of Cleopatra tangerine zygotic embryos: a model for somatic embryo encapsulation 总被引:1,自引:0,他引:1
Nieves Nadina Lorenzo Jose C. Blanco Maria de los A. González Justo Peralta Hipólito Hernández Martha Santos Ramón Concepción Oscar Borroto Carlos G. Borroto Eduviges Tapia Raúl Martinez Marcos E. Fundora Zaida González Alfredo 《Plant Cell, Tissue and Organ Culture》1998,54(2):77-83
Synthetic seed technology may be of value in breeding programs and allow the propagation of many elite genotype-derived plants
in a short time. In this work, a range of artificial endosperm treatments of Cleopatra tangerine zygotic embryos were evaluated
for suitability for encapsulation of somatic embryos. Different complexing ions in the form of alginate capsules, zeolite
as an ion exchanger and the relationship between capsule-nutrient gel on germination of zygotic embryos, were evaluated. Artificial
endosperm assays showed that abscisic acid (1 μM) and mannitol (0.25 M) delayed germination and conversion of zygotic embryos,
whereas amino acid supplements (proline, glutamic acid and arginine) accelerated the conversion process. An artificial endosperm
was used to encapsulate somatic and zygotic embryos. After encapsulation, zygotic embryos germinated after four days of culture
while somatic embryos germinated asynchronously after 20 days. Somatic embryo-derived plantlets showed greater vigour than
zygotic embryo-derived plantlets. Results showed that this artificial endosperm is adequate for Cleopatra tangerine somatic
embryo germination and conversion into plants.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
9.
Zaida Agüera Xandra Romero Jon Arcelus Isabel Sánchez Nadine Riesco Susana Jiménez-Murcia Jana González-Gómez Roser Granero Nuria Custal Monica Montserrat-Gil de Bernabé Salomé Tárrega Rosa M. Ba?os Cristina Botella Rafael de la Torre José C. Fernández-García José M. Fernández-Real Gema Frühbeck Javier Gómez-Ambrosi Francisco J. Tinahones Ana B. Crujeiras Felipe F. Casanueva José M. Menchón Fernando Fernández-Aranda 《PloS one》2015,10(11)
The restoration of body composition (BC) parameters is considered to be one of the most important goals in the treatment of patients with anorexia nervosa (AN). However, little is known about differences between AN diagnostic subtypes [restricting (AN-R) and binge/purging (AN-BP)] and weekly changes in BC during refeeding treatment. Therefore, the main objectives of our study were twofold: 1) to assess the changes in BC throughout nutritional treatment in an AN sample and 2) to analyze predictors of BC changes during treatment, as well as predictors of treatment outcome. The whole sample comprised 261 participants [118 adult females with AN (70 AN-R vs. 48 AN-BP), and 143 healthy controls]. BC was measured weekly during 15 weeks of day-hospital treatment using bioelectrical impedance analysis (BIA). Assessment measures also included the Eating Disorders Inventory-2, as well as a number of other clinical indices. Overall, the results showed that AN-R and AN-BP patients statistically differed in all BC measures at admission. However, no significant time×group interaction was found for almost all BC parameters. Significant time×group interactions were only found for basal metabolic rate (p = .041) and body mass index (BMI) (p = .035). Multiple regression models showed that the best predictors of pre-post changes in BC parameters (namely fat-free mass, muscular mass, total body water and BMI) were the baseline values of BC parameters. Stepwise predictive logistic regressions showed that only BMI and age were significantly associated with outcome, but not with the percentage of body fat. In conclusion, these data suggest that although AN patients tended to restore all BC parameters during nutritional treatment, only AN-BP patients obtained the same fat mass values as healthy controls. Put succinctly, the best predictors of changes in BC were baseline BC values, which did not, however, seem to influence treatment outcome. 相似文献
10.
Carolina I. Cura Tomas Duffy Raúl H. Lucero Margarita Bisio Julie Péneau Matilde Jimenez-Coello Eva Calabuig María J. Gimenez Edward Valencia Ayala Sonia A. Kjos José Santalla Susan M. Mahaney Nelly M. Cayo Claudia Nagel Laura Barcán Edith S. Málaga Machaca Karla Y. Acosta Viana Laurent Brutus Susana B. Ocampo Christine Aznar Cesar A. Cuba Cuba Ricardo E. Gürtler Janine M. Ramsey Isabela Ribeiro John L. VandeBerg Zaida E. Yadon Antonio Osuna Alejandro G. Schijman 《PLoS neglected tropical diseases》2015,9(5)