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1.
Adriana R. Aguilar-Melo Sophie Calmé Braulio Pinacho-Guendulain Sandra E. Smith-Aguilar Gabriel Ramos-Fernández 《American journal of primatology》2020,82(1):e23077
Some social species exhibit high levels of fission–fusion dynamics (FFD) that improve foraging efficiency. In this study, we shed light on the way that FFD allows animal groups to cope with fluctuations in fruit availability. We explore the relative contribution of fruit availability and social factors like sex in determining association and proximity patterns in spider monkeys. We tested the influence of fruit availability and social factors on the association and proximity patterns using three-year data from a group of spider monkeys in the Yucatan Peninsula of Mexico. We identified subgroup members and estimated their Interindividual distances through instantaneous scan sampling. We evaluated fruit availability by monitoring the phenology of the 10 most important food tree species for spider monkeys in the study site. Social network analyses allowed us to evaluate association and proximity patterns in subgroups. We showed that association patterns vary between seasons, respond to changes in fruit availability, and are influenced by the sex of individuals, likely reflecting biological and behavioral differences between sexes and the interplay between ecological and social factors. In contrast, proximity patterns were minimally affected by changes in fruit availability, suggesting that social factors are more important than food availability in determining cohesion within subgroups. 相似文献
2.
Katherina Walz Devon Cohen Paul M. Neilsen Joseph Foster II. Francesco Brancati Korcan Demir Richard Fisher Michelle Moffat Nienke E. Verbeek Kathrine Bjørgo Adriana Lo Castro Paolo Curatolo Giuseppe Novelli Clemer Abad Cao Lei Lily Zhang Oscar Diaz-Horta Juan I. Young David F. Callen Mustafa Tekin 《Human genetics》2015,134(2):181-190
3.
Camila Simioni Vanzin Caroline Paula Mescka Bruna Donida Tatiane Grazieli Hammerschimidt Graziela S. Ribas Janaína Kolling Emilene B. Scherer Laura Vilarinho Célia Nogueira Adriana Simon Coitinho Moacir Wajner Angela T. S. Wyse Carmen Regla Vargas 《Cellular and molecular neurobiology》2015,35(6):899-911
4.
Xinzhu Deng David Michaelson Jason Tchieu Jin Cheng Diana Rothenstein Regina Feldman Sang-gyu Lee John Fuller Adriana Haimovitz-Friedman Lorenz Studer Simon Powell Zvi Fuks E. Jane Albert Hubbard Richard Kolesnick 《PloS one》2015,10(6)
Mammalian NOTCH1-4 receptors are all associated with human malignancy, although exact roles remain enigmatic. Here we employ glp-1(ar202), a temperature-sensitive gain-of-function C. elegans NOTCH mutant, to delineate NOTCH-driven tumor responses to radiotherapy. At ≤20°C, glp-1(ar202) is wild-type, whereas at 25°C it forms a germline stem cell⁄progenitor cell tumor reminiscent of human cancer. We identify a NOTCH tumor phenotype in which all tumor cells traffic rapidly to G2⁄M post-irradiation, attempt to repair DNA strand breaks exclusively via homology-driven repair, and when this fails die by mitotic death. Homology-driven repair inactivation is dramatically radiosensitizing. We show that these concepts translate directly to human cancer models. 相似文献
5.
Adriana Calderaro Giovanna Piccolo Chiara Gorrini Sara Montecchini Sabina Rossi Maria Cristina Medici Carlo Chezzi Georges Snounou 《PloS one》2012,7(10)
It has been proposed that ovale malaria in humans is caused by two closely related but distinct species of malaria parasites: P. ovale curtisi and P. ovale wallikeri. We have extended and optimized a Real-time PCR assay targeting the parasite’s small subunit ribosomal RNA (ssrRNA) gene to detect both these species. When the assay was applied to 31 archival blood samples from patients diagnosed with P. ovale, it was found that the infection in 20 was due to P. ovale curtisi and in the remaining 11 to P. ovale wallikeri. Thus, this assay provides a useful tool that can be applied to epidemiological investigations of the two newly recognized distinct P. ovale species, that might reveal if these species also differ in their clinical manifestation, drugs susceptibility and relapse periodicity. The results presented confirm that P. ovale wallikeri is not confined to Southeast Asia, since the majority of the patients analyzed in this study had acquired their P. ovale infection in African countries, mostly situated in West Africa. 相似文献
6.
Imran Haq James?A. Irving Sarah?V. Faull Jennifer?A. Dickens Adriana Ordó?ez Didier Belorgey Bibek Gooptu David?A. Lomas 《Bioscience reports》2013,33(3)
The common severe Z mutation (E342K) of α1-antitrypsin forms intracellular polymers that are associated with liver cirrhosis. The native fold of this protein is well-established and models have been proposed from crystallographic and biophysical data for the stable inter-molecular configuration that terminates the polymerization pathway. Despite these molecular ‘snapshots’, the details of the transition between monomer and polymer remain only partially understood. We surveyed the RCL (reactive centre loop) of α1-antitrypsin to identify sites important for progression, through intermediate states, to polymer. Mutations at P14P12 and P4, but not P10P8 or P2P1′, resulted in a decrease in detectable polymer in a cell model that recapitulates the intracellular polymerization of the Z variant, consistent with polymerization from a near-native conformation. We have developed a FRET (Förster resonance energy transfer)-based assay to monitor polymerization in small sample volumes. An in vitro assessment revealed the position-specific effects on the unimolecular and multimolecular phases of polymerization: the P14P12 region self-inserts early during activation, while the interaction between P6P4 and β-sheet A presents a kinetic barrier late in the polymerization pathway. Correspondingly, mutations at P6P4, but not P14P12, yield an increase in the overall apparent activation energy of association from ~360 to 550 kJ mol−1. 相似文献
7.
Harold Prada Laura Ávila Roberto Sierra Adriana Bernal Silvia Restrepo 《Revista iberoamericana de micología》2009,26(3):198-201
Endophytic fungi produce a great variety of secondary metabolites both in vivo and in vitro. In this study, we characterized the ability of a sterile-mycelium endophytic fungus isolated from Espeletia sp. to control the growth of Phytophthora infestans in Petri dishes. Sequence from the ITS regions (internal transcribed spacer) of the endophyte showed 94% similarity to Diaporthe phaseolorum's. The antagonistic interaction between Diaporthe sp. and P. infestans was evaluated in three different culture media. Diaporthe sp. showed an antagonistic effect towards P. infestans, with some variation depending on which medium was used. In an attempt to identify possible genes involved in this antagonism, we detected a gene from the endophyte encoding an amylase, which was differentially expressed during this biotic interaction. 相似文献
8.
Jovani Catalán-Dibene Suzanne M. Johnson Ricardo Eaton Adriana L. Romero-Olivares Raúl C. Baptista-Rosas Demosthenes Pappagianis Meritxell Riquelme 《Fungal biology》2014,118(3):330-339
Coccidioidomycosis (Valley Fever) represents a serious threat to inhabitants of endemic areas of North America. Despite successful clinical isolations of the fungal etiological agent, Coccidioides spp., the screening of environmental samples has had low effectiveness, mainly because of the poor characterization of Coccidioides ecological niche. We explored Valle de las Palmas, Baja California, Mexico, a highly endemic area near the U.S.–Mexico border, where we previously detected Coccidioides via culture-independent molecular methods. By testing the serum from 40-trapped rodents with ELISA, we detected antibodies against Coccidioides in two species: Peromyscus maniculatus and Neotoma lepida. This study comprises the first report of wild rodent serum tested for coccidioidal antibodies, and sets the basis to analyze this pathogen in its natural environment and explore its potential ecological niche. 相似文献
9.
Fernanda Veruska Narciso José A. Barela Stefane A. Aguiar Adriana N. S. Carvalho Sergio Tufik Marco Túlio de Mello 《PloS one》2016,11(4)
The purpose of the study was to investigate the effects of shift work on the psychomotor and postural performance of night workers. The study included 20 polysomnography technicians working schedule of 12-h night shift by 36-h off. On the first day of protocol, the body mass and height were measured, and an actigraph was placed on the wrist of each participant. On the second day of protocol, sleepiness by Karolinska Sleepiness Scale, postural control by force platform (30 seconds) and psychomotor performance by Psychomotor Vigilance Task (10 minutes) were measured before and after 12-h night work. Results showed that after 12-h night work, sleepiness increased by 59% (p<0.001), postural control variables increased by 9% (p = 0.048), and 14% (p = 0.006). Mean reaction time, and the number of lapses of attention increased by 13% (p = 0.006) and 425% (p = 0.015), respectively, but the mean reciprocal reaction time decreased by 7%. In addition, there were correlations between sleepiness and postural control variables with opened eyes (r = 0.616, 95% confidence interval [CI] = 0.361–0.815; r = 0.538; 95% CI = 0.280–0.748) and closed eyes (r = 0.557; 95% CI = 0.304–0.764, r = 0497; 95% CI = 0.325–0.715) and a pronounced effect of sleepiness on postural sway (R2 = 0.393; 95% CI = 0.001–0.03). Therefore, 12-h night work system and sleepiness showed a negative impact in postural and psychomotor vigilance performance of night workers. As unexpected, the force platform was feasibility to detect sleepiness in this population, underscoring the possibility of using this method in the workplace to prevent occupational injuries and accidents. 相似文献
10.