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141.
Devy Widjaja Alessandro Montalto Elke Vlemincx Daniele Marinazzo Sabine Van Huffel Luca Faes 《PloS one》2015,10(6)
An analysis of cardiorespiratory dynamics during mental arithmetic, which induces stress, and sustained attention was conducted using information theory. The information storage and internal information of heart rate variability (HRV) were determined respectively as the self-entropy of the tachogram, and the self-entropy of the tachogram conditioned to the knowledge of respiration. The information transfer and cross information from respiration to HRV were assessed as the transfer and cross-entropy, both measures of cardiorespiratory coupling. These information-theoretic measures identified significant nonlinearities in the cardiorespiratory time series. Additionally, it was shown that, although mental stress is related to a reduction in vagal activity, no difference in cardiorespiratory coupling was found when several mental states (rest, mental stress, sustained attention) are compared. However, the self-entropy of HRV conditioned to respiration was very informative to study the predictability of RR interval series during mental tasks, and showed higher predictability during mental arithmetic compared to sustained attention or rest. 相似文献
142.
Chiara Barbieri Paul Heggarty Daniele Yang Yao Gianmarco Ferri Sara De Fanti Stefania Sarno Graziella Ciani Alessio Boattini Donata Luiselli Davide Pettener 《American journal of physical anthropology》2014,155(4):600-609
The Yanesha are a Peruvian population who inhabit an environment transitional between the Andes and Amazonia. They present cultural traits characteristic of both regions, including in the language they speak: Yanesha belongs to the Arawak language family (which very likely originated in the Amazon/Orinoco lowlands), but has been strongly influenced by Quechua, the most widespread language family of the Andes. Given their location and cultural make‐up, the Yanesha make for an ideal case study for investigating language and population dynamics across the Andes‐Amazonia divide. In this study, we analyze data from high and mid‐altitude Yanesha villages, both Y chromosome (17 STRs and 16 SNPs diagnostic for assigning haplogroups) and mtDNA data (control region sequences and 3 SNPs and one INDEL diagnostic for assigning haplogroups). We uncover sex‐biased genetic trends that probably arose in different stages: first, a male‐biased gene flow from Andean regions, genetically consistent with highland Quechua‐speakers and probably dating back to Inca expansion; and second, traces of European contact consistent with Y chromosome lineages from Italy and Tyrol, in line with historically documented migrations. Most research in the history, archaeology and linguistics of South America has long been characterized by perceptions of a sharp divide between the Andes and Amazonia; our results serve as a clear case‐study confirming demographic flows across that ‘divide’. Am J Phys Anthropol 155:600–609, 2014. © 2014 The Authors. American journal of physical Anthropology published by Wiley Periodocals, Inc. 相似文献
143.
144.
Sandra Urbanelli Daniele Porretta Valentina Mastrantonio Romeo Bellini Giuseppe Pieraccini Riccardo Romoli Graziano Crasta Giuseppe Nascetti 《Evolution; international journal of organic evolution》2014,68(10):3030-3038
Natural selection can act against maladaptive hybridization between co‐occurring divergent populations leading to evolution of reproductive isolation among them. A critical unanswered question about this process that provides a basis for the theory of speciation by reinforcement, is whether natural selection can cause hybridization rates to evolve to zero. Here, we investigated this issue in two sibling mosquitoes species, Aedes mariae and Aedes zammitii, that show postmating reproductive isolation (F1 males sterile) and partial premating isolation (different height of mating swarms) that could be reinforced by natural selection against hybridization. In 1986, we created an artificial sympatric area between the two species and sampled about 20,000 individuals over the following 25 years. Between 1986 and 2011, the composition of mating swarms and the hybridization rate between the two species were investigated across time in the sympatric area. Our results showed that A. mariae and A. zammitii have not completed reproductive isolation since their first contact in the artificial sympatric area. We have discussed the relative role of factors such as time of contact, gene flow, strength of natural selection, and biological mechanisms causing prezygotic isolation to explain the observed results. 相似文献
145.
Daniele Silvestro Georg Zizka Katharina Schulte 《Evolution; international journal of organic evolution》2014,68(1):163-175
The evolution of key innovations, novel traits that promote diversification, is often seen as major driver for the unequal distribution of species richness within the tree of life. In this study, we aim to determine the factors underlying the extraordinary radiation of the subfamily Bromelioideae, one of the most diverse clades among the neotropical plant family Bromeliaceae. Based on an extended molecular phylogenetic data set, we examine the effect of two putative key innovations, that is, the Crassulacean acid metabolism (CAM) and the water‐impounding tank, on speciation and extinction rates. To this aim, we develop a novel Bayesian implementation of the phylogenetic comparative method, binary state speciation and extinction, which enables hypotheses testing by Bayes factors and accommodates the uncertainty on model selection by Bayesian model averaging. Both CAM and tank habit were found to correlate with increased net diversification, thus fulfilling the criteria for key innovations. Our analyses further revealed that CAM photosynthesis is correlated with a twofold increase in speciation rate, whereas the evolution of the tank had primarily an effect on extinction rates that were found five times lower in tank‐forming lineages compared to tank‐less clades. These differences are discussed in the light of biogeography, ecology, and past climate change. 相似文献
146.
Daniele Amadio Filomena Fezza Giuseppina Catanzaro Ottaviano Incani Guus van Zadelhoff Alessandro Finazzi Agrò Mauro Maccarrone 《Biochimie》2010
The biological activity of endocannabinoids like anandamide (AEA) and 2-arachidonoylglycerol (2-AG) is subjected in vivo to a “metabolic control”, exerted mainly by catabolic enzymes. AEA is inactivated by fatty acid amide hydrolase (FAAH), that is inhibited competitively by hydroxyanandamides (HAEAs) generated from AEA by lipoxygenase activity. Among these derivatives, 15-HAEA has been shown to be an effective (Ki ∼0.6 μM) FAAH inhibitor, that blocks also type-1 cannabinoid receptor (CB1R) but not other components of the “endocannabinoid system (ECS)”, like the AEA transporter (AMT) or CB2R. Here, we extended the study of the effect of 15-HAEA on the AEA synthetase (NAPE-PLD) and the AEA-binding vanilloid receptor (TRPV1), showing that 15-HAEA activates the former (up to ∼140% of controls) and inhibits the latter protein (down to ∼70%). We also show that 15-HAEA halves the synthesis of 2-AG and almost doubles the transport of this compound across the membrane. In addition, we synthesized methyl and acetyl derivatives of 15-HAEA (15-MeOAEA and 15-AcOAEA, respectively), in order to check their ability to modulate FAAH and the other ECS elements. In fact, methylation and acetylation are common biochemical reactions in the cellular environment. We show that 15-MeOAEA, unlike 15-AcOAEA, is still a powerful competitive inhibitor of FAAH (Ki ∼0.7 μM), and that both derivatives have negligible interactions with the other proteins of ECS. Therefore, 15-MeOAEA is a FAAH inhibitor more selective than 15-HAEA. Further molecular dynamics analysis gave clues to the molecular requirements for the interaction of 15-HAEA and 15-MeOAEA with FAAH. 相似文献
147.
148.
Ivana Caputo Maria Vittoria Barone Marilena Lepretti Stefania Martucciello Ivan Nista Riccardo Troncone Salvatore Auricchio Daniele Sblattero Carla Esposito 《生物化学与生物物理学报:疾病的分子基础》2010,1802(9):717-727
Celiac disease is characterized by the secretion of IgA-class autoantibodies that target tissue transglutaminase (tTG). It is now recognized that anti-tTG antibodies are functional and not mere bystanders in the pathogenesis of celiac disease. Here we report that interaction between anti-tTG antibodies and extracellular membrane-bound tTG inhibits peptide 31–43 (but not peptide 57–68) uptake by cells, thereby impairing the ability of p31–43 to drive Caco-2 cells into S-phase. This effect did not involve tTG catalytic activity. Because anti-tTG antibodies interfered with epidermal growth factor endocytosis, we assume that they exert their effect by reducing peptide 31–43 endocytosis. Our results suggest that cell-surface tTG plays a hitherto unknown role in the regulation of gliadin peptide uptake and endocytosis. 相似文献
149.
Daniele Balducci Ilaria Lazzari Magda Monari Fabio Piccinelli Gianni Porzi 《Amino acids》2010,38(3):829-837
A new and convenient stereocontrolled synthesis of the optically pure (S)-α-methyl,α-amino acids 6(a–d) that exploits the chiral synthon 1,4-N,N-[(S)-1-phenylethyl]-piperazine-2,5-dione (1) is described. The (S)-1-phenylethyl group, bonded to each of the N-atoms of the 2,5-diketopiperazine, acts as a chiral inductor in the first alkylation, while the steric hindrance appears
to be the determining factor of stereocontrol in third and forth alkylation. 相似文献
150.
Valentina Alessandria Paola Dolci Kalliopi Rantsiou Daniele Pattono Alessandra Dalmasso Tiziana Civera Luca Cocolin 《World journal of microbiology & biotechnology》2010,26(12):2211-2221
The present study aimed to evaluate the dominant microbial community naturally present in the Planalto de Bolona cheese, produced in the Cape Verde Islands. Samples of milk, curd and cheese from two different producers were examined through
culture-dependent and independent-methods. Traditional plating and genetic identification of lactic acid bacteria (LAB) and
yeast isolates were carried out. Moreover, DNA and RNA extracted directly from samples were subjected to Polymerase Chain
Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE). Concerning the LAB population, a total of 278 isolates were identified:
Lactococcus lactis subsp. lactis and Enterococcus faecium represented the most isolated species. Regarding yeasts, the analysis of isolates throughout the manufacturing period showed
a consistent presence of the genus Candida. Divergences in species detection between culture-dependent and culture-independent methods were observed, as well as between
DNA and RNA analysis. PCR-DGGE underlined high heterogeneity among bacterial species while yeast microbiota was dominated
by Aureobasidium pullulans at DNA level. The obtained results represent a first approach in the understanding of the Planalto de Bolona cheese microbial ecology and consequently may constitute a first step towards the full comprehension of the microbiota of
this artisanal cheese produced in unusual environmental conditions in the Cape Verde Islands. 相似文献