Catalytic cancer therapy targets cancer cells by exploiting the specific characteristics of the tumor microenvironment (TME). TME-based catalytic strategies rely on the use of molecules already ...present in the TME. Amino groups seem to be a suitable target, given the abundance of proteins and peptides in biological environments. Here we show that catalytic CuFe2O4 nanoparticles are able to foster transaminations with different amino acids and pyruvate, another key molecule present in the TME. We observed a significant in cellulo decrease in glutamine and alanine levels up to 48 h after treatment. In addition, we found that di- and tripeptides also undergo catalytic transamination, thereby extending the range of the effects to other molecules such as glutathione disulfide (GSSG). Mechanistic calculations for GSSG transamination revealed the formation of an imine between the oxo group of pyruvate and the free −NH2 group of GSSG. Our results highlight transamination as alternative to the existing toolbox of catalytic therapies.
Studies of complex networks show that nodes with high centrality scores are important to network structure and stability. Following this rationale, centrality measures can be used to (i) identify ...keystone species in ecological networks, a major issue in community ecology, and (ii) differentiate the keystone species concept, e.g. species may play a key role in a network for different topological reasons. In 34 pollination communities we examine the relationship between the generalization level of species (
ND) and two complementary centrality indices: closeness (
CC) and betweenness centrality (
BC).
CC measures the proximity of a species to all other species in the community, while
BC describes the importance of a species as a connector. Most networks had a linear
ND–
CC relationship with a minimum
CC value of 0.41. Hence, species were close to each and will be likely to be rapidly affected by disturbances. Contrarily, in most networks, the
ND–
BC relationships were power-law distributed with exponents larger than one. Only 59% of the species were connectors (
BC
>
0). In particular, there was a connector threshold value of
ND
=
0.46. Species above this threshold represent ∼40%, almost all of which were connectors. These results indicate that in pollination systems the most generalized species are usually network keystone species, playing at least two roles: (i) interact closely with most other species (high
CC) and (ii) connect otherwise unconnected subnetworks (high
BC). We discuss the implications of centrality measures to community-based conservation ecology.
Regulation of adult neural stem cell (NSC) number is critical for lifelong neurogenesis. Here, we identified a post‐transcriptional control mechanism, centered around the microRNA 204 (miR‐204), to ...control the maintenance of quiescent (q)NSCs. miR‐204 regulates a spectrum of transcripts involved in cell cycle regulation, neuronal migration, and differentiation in qNSCs. Importantly, inhibition of miR‐204 function reduced the number of qNSCs in the subependymal zone (SEZ) by inducing pre‐mature activation and differentiation of NSCs without changing their neurogenic potential. Strikingly, we identified the choroid plexus of the mouse lateral ventricle as the major source of miR‐204 that is released into the cerebrospinal fluid to control number of NSCs within the SEZ. Taken together, our results describe a novel mechanism to maintain adult somatic stem cells by a niche‐specific miRNA repressing activation and differentiation of stem cells.
Synopsis
Systemic niche control in adult neurogenesis remains incompletely understood. Here, miR‐204 is shown to be transferred from the choroid plexus to neural stem cells (NSC) to maintain their undifferentiated state, revealing a long‐distance, post‐transcriptional fate control mechanism.
Quiescent NSCs of the subependymal zone exhibit high mRNA, but not protein, levels of neurogenic fate determinants.
Translation of neurogenic mRNAs is controlled by miR‐204.
Choroid plexus epithelium secretes miR‐204 within extracellular vesicles into the cerebrospinal fluid, regulating NSC maintenance.
Neurogenic versus stem cell fate is controlled by long‐distance transfer of secreted miR‐204.
Social and academic interest in animal abuse has recently increased thanks to greater awareness of the importance of biodiversity in promoting sustainability. The redefinition of human-animal ...relationships, in the context of the fight against speciesism and the defense of veganism, has also contributed to this greater attention. Moreover, public awareness of animal rights has strengthened social reactions to violence against animals, though there are still some social sectors that are indifferent to these changes. Thus, better knowledge of the psychological mechanisms underlying reactions to animal abuse could contribute to better informal, social control of such abuse. The main aim of this study is to analyze the relationships between psychopathy, empathy with people, and empathy with nature arising from people's reactions to protected and domestic animal abuse and illegal dumping. Also, as previous studies have shown differences between men and women, both in animal abuse and in personality traits, thus gender is taken into account when analyzing these relationships. A total of 409 people, resident in a highly environmentally protected territory, participated in this study. They were aged between 18 and 82 years old and 49.9% women. Participants were asked about assigned punishments, as well as the probability of intervening personally and/or calling the police, in relation to ten scenarios, based on press releases, describing one of three types of transgression of environmental laws: abuse of protected animals, abuse of domestic animals or illegal dumping. They also responded to Spanish adaptations of the Inventory of Callous Unemotional Traits, the Basic Empathy Scale, the Dispositional Empathy with Nature Scale, and the Social Desirability Scale. Each participant was randomly given ten scenarios corresponding to just one transgression type but all the personality scales. Results show that people's reactions were greater for abuse of domestic than protected animals or for illegal dumping, irrespective of gender. Empathy with nature was related to the reaction against animal abuse more than empathy with people and psychopathy. Results are discussed highlighting the need for future research into similarities and differences between animal abuse and other types of environmental offences, which have many victims but no single being suffering.
The remarkable differences that have been detected by metagenomics in the genomes of strains of the same bacterial species are difficult to reconcile with the widely accepted paradigm that periodic ...selection within bacterial populations will regularly purge genomic diversity by clonal replacement. We have found that many of the genes that differ between strains affect regions that are potential phage recognition targets. We therefore propose the constant-diversity dynamics model, in which the diversity of prokaryotic populations is preserved by phage predation. We provide supporting evidence for this model from metagenomics, mathematical analysis and computer simulations. Periodic selection and phage predation dynamics are not mutually exclusive; we compare their predictions to shed light on the ecological circumstances under which each type of dynamics could predominate.
A total of 38 phenolic compounds in the solid/liquid extracts of five Lamiaceae spices, rosemary, oregano, sage, basil, and thyme, were identified in the present study using LC-ESI-MS/MS. These ...compounds were distributed in four major categories, namely, hydroxycinnamic acid derivatives, hydroxybenzoic acid derivatives, flavonoids, and phenolic terpenes. Among them, the category of flavonoids was the largest, with 17 compounds. Identification of the phenolic compounds was carried out by comparing retention times and mass spectra with those of authentic standards. If standards were unavailable, phenolic compounds were identified on the basis of accurate mass of pseudomolecular M − H− ions and tandem mass spectrometry (MS/MS) data. The results of accurate mass measurements fit well with the elemental composition of the compounds. The diagnostic fragmentation patterns of the compounds during collision-induced dissociation (CID) elucidated the structural information of the compounds analyzed.
Infants are able to entertain hypotheses about complex events and to modify them rationally when faced with inconsistent evidence. These capacities suggest that infants can use elementary logical ...representations to frame and prune hypotheses. By presenting scenes containing ambiguities about the identity of an object, here we show that 12- and 19-month-old infants look longer at outcomes that are inconsistent with a logical inference necessary to resolve such ambiguities. At the moment of a potential deduction, infants' pupils dilated, and their eyes moved toward the ambiguous object when inferences could be computed, in contrast to transparent scenes not requiring inferences to identify the object. These oculomotor markers resembled those of adults inspecting similar scenes, suggesting that intuitive and stable logical structures involved in the interpretation of dynamic scenes may be part of the fabric of the human mind.
•Indicators of soil quality index (SQI) were selected by Network analysis (NTA).•SQI from NTA were compare with those obtained by principal component analysis (PCA).•NTA generated SQIs that reflected ...more accurately the different soil uses.•Agricultural soils quality was deteriorated by the loss of organic matter.
There is an urgent need to conserve and improve the quality of agricultural soils in the coming decades. Decision tools capable of providing reliable information about soil quality are needed, and soil quality index (SQI) is one of the most used. Principal component analysis (PCA) is the common methodology to calculate it, however in some cases fails to differentiate soil quality properly. Therefore, the aim of this work is to assess a SQI through a different methodology as network analysis (NTA) and compare it with PCA, assuming that soil uses affect soil qualities differently. From soils with different uses (rainfed, olive grove and forest) network analysis and principal component analysis have been used to select a minimum dataset (MDS) to generate SQI from 36 physical, chemical and biological soil variables. Using NTA, geometric mean of the enzyme activities (GMEAN), bulk density (BD) and phosphatase activity (phos) where selected as indicators, while PCA selected total organic carbon (TOC), free Fe oxides (FeF), crystalline Mn oxides (MnX), pH, electrical conductivity (EC) and percentage of coarse sand (CS). Four SQI were calculated from each MDS through linear and non-linear scoring equations and by additive integration and weights. The SQI generated by NTA were more useful than those generated by PCA, as in addition to having fewer indicators they were able to better differentiate the uses in the study. This greater resolution capacity of the NTA would be the consequence of a better selection of indicators using this method than using PCA.
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