The mammalian gut microbiota harbors a diverse ecosystem where hundreds of bacterial species interact with each other and their host. Given that bacteria use signals to communicate and regulate group ...behaviors (quorum sensing), we asked whether such communication between different commensal species can influence the interactions occurring in this environment. We engineered the enteric bacterium, Escherichia coli, to manipulate the levels of the interspecies quorum sensing signal, autoinducer-2 (AI-2), in the mouse intestine and investigated the effect upon antibiotic-induced gut microbiota dysbiosis. E. coli that increased intestinal AI-2 levels altered the composition of the antibiotic-treated gut microbiota, favoring the expansion of the Firmicutes phylum. This significantly increased the Firmicutes/Bacteroidetes ratio, to oppose the strong effect of the antibiotic, which had almost cleared the Firmicutes. This demonstrates that AI-2 levels influence the abundance of the major phyla of the gut microbiota, the balance of which is known to influence human health.
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•Streptomycin almost clears Firmicutes as Bacteroidetes dominate the gut microbiota•Engineered Escherichia coli manipulate AI-2 levels in the mouse gut•AI-2 produced by E. coli favors the Firmicutes while hindering the Bacteroidetes•AI-2 can shape the microbiota composition under conditions of dysbiosis
The balance between the Bacteroidetes and Firmicutes phyla in the gut bacterial community influences host health. Thompson et al. investigate the impact of the interspecies signal autoinducer-2 on this balance. Despite the streptomycin-induced dominance of the microbiota by the Bacteroidetes, increased AI-2 counteracts antibiotic-induced dysbiosis and favors Firmicutes.
With only 32% of women in the labor market, Guatemala has one of the lowest rates of female labor force participation (FLFP) in the Latin America and Caribbean region and in the world. We explore ...information from different micro data sets, including the most recent population censuses (2002 and 2018) to assess the drivers of recent progress. Between 2002 and 2018, FLFP increased from an average of 26% to 32% nationwide. This increase was partly explained by increases in the school attainment of women, reduction in fertility and the country's structural transformation towards services. However, a large part of the increase remains unexplained. Exploring 2018 data, we show that social norms, attitudes towards women and public policies are important determinants of FLFP. The analysis suggests that, taken together, these factors can all become an important source of increased participation of women in the labor market moving forward
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Foreign firms have a more educated workforce and pay higher wages than domestic firms even after controlling for worker quality, at a given moment in time. This does not imply that foreign ownership ...improves the labor market outcomes of the workers since foreign investment may be guided by unobservable firm and worker characteristics correlated with schooling or wages. This paper asks whether foreign investors acquire firms with high human capital or wages, or whether foreign acquisition improves these outcomes. Using a matched employer–employee data set, I find that foreign acquisitions of domestic firms have small effects on the human capital and on average wages of the acquired firms. Instead, foreign investors “cherry pick” those domestic firms that are already very similar to the group of existing foreign firms.
Natural extracellular matrices (ECM) are currently being studied as an alternative source for organ transplantation or as new solutions to treat kidney injuries, which can evolve to end‐stage renal ...disease, a life devastating condition. This paper provides an overview on the current knowledge in kidney ECM and its usefulness on future investigations. The composition and structure of kidney ECM is herein associated with its intrinsic capacity of remodeling and repair after insult. Moreover, it provides a deeper insight on altered ECM components during disease. The use of decellularized kidney matrices is discussed in the second part of the review, with emphasis on how these matrices contribute to tissue‐specific differentiation of embryonic, pluripotent, and other stem cells. The evolution on the field toward different uses of xenogeneic ECM as a biological scaffold material is discussed, namely the major outcomes on whole kidney recellularization and its in vivo implantation. At last, the recent literature on the use of processed kidney decellularized ECM to produce diverse biomaterial substrates, such as hydrogels, membranes, and bioinks are reviewed, with emphasis on future perspectives of its translation into the clinic.
This review encloses the most recent and relevant research on the kidney extracellular matrix, including whole kidney decellularization and repopulation as an alternative for organ transplantation and the fabrication of biomaterials from kidney decellularized matrices. These include the development of hydrogels, 3D porous scaffolds, bioinks, and membranes as new tissue engineered strategies.
Human working memory capacity develops during childhood and is a strong predictor of future academic performance, in particular, achievements in mathematics and reading. Predicting working memory ...development is important for the early identification of children at risk for poor cognitive and academic development. Here we show that structural and functional magnetic resonance imaging data explain variance in children's working memory capacity 2 years later, which was unique variance in addition to that predicted using cognitive tests. While current working memory capacity correlated with frontoparietal cortical activity, the future capacity could be inferred from structure and activity in basal ganglia and thalamus. This gives a novel insight into the neural mechanisms of childhood development and supports the idea that neuroimaging can have a unique role in predicting children's cognitive development.
We contribute to the technology, skills, and jobs debate by exploiting a novel dataset for Chilean firms between 2007 and 2013, with information on the firms' adoption of complex software used in ...client management, production, or administration and business software packages. Instrumental variables estimates show that, in the medium-run, adoption of this complex software reallocates employment away from professional and technical workers, toward administrative and unskilled workers (production and services). Adoption also increases the use of routine and manual tasks and reduces that of abstract tasks within firms. The contrast between ours and previous findings shows that labour market impacts of technology adoption hinge on the type of technology and its complementarity with the skills content of occupations.
This paper revisits the question of how trade affects labor market outcomes in a developing country setting. We explore the fact that plants face varying degrees of exposure to the enforcement of ...labor market regulations, and rely on Brazil's currency crisis in 1999 as an exogenous source of variation in access to foreign markets. Using administrative data on employers and their employees, and on the enforcement of labor regulations at the city level over Brazil's crisis period, we document that the way a currency shock affects employment depends on the stringency of de facto labor market regulations. In particular, we show for Brazil, a country with strict de jure labor regulation, that after a depreciation, plants facing stricter enforcement of the labor law increase employment by less than plants facing looser enforcement. These findings are consistent with the hypothesis that, in the context of strict de jure labor market regulations, increased enforcement limits the plant-level productivity gains associated with a more global market. Therefore, increasing the flexibility of de jure regulations may allow for broader access to the gains from trade.
Several episodes of market-oriented reforms in developing countries have been accompanied by a significant rise in work outside of the formal economy. This paper investigates whether the impact of ...trade on formal employment is mediated by the strength of labour regulations. We rely on data from the Brazilian Census that provides information on workers' demographics and employment, including job formality status. Our estimation strategy exploits quasi-exogenous changes in industry-level real exchange rates to explore the likelihood of informality across employers exposed to varying degrees of de facto labour regulations. We further utilize two key features of Brazilian labour institutions - budgetary decisions about the availability of resources occur at the federal level, while decisions about where to inspect occur at the local level - to instrument for labour enforcement. Our results suggest that strict labour regulations may lead to a precarization of employment, rather than offering protection for workers.
Soybean is an economically important plant, and its production is affected in soils with high salinity levels. It is important to understand the adaptive mechanisms through which plants overcome this ...kind of stress and to identify potential genes for improving abiotic stress tolerance. RNA-Seq data of two
Glycine max
cultivars, a drought-sensitive (C08) and a tolerant (Conquista), subjected to different periods of salt stress were analyzed. The transcript expression profile was obtained using a transcriptogram approach, comparing both cultivars and different times of treatment. After 4 h of salt stress, Conquista cultivar had 1400 differentially expressed genes, 647 induced and 753 repressed. Comparative expression revealed that 719 genes share the same pattern of induction or repression between both cultivars. Among them, 393 genes were up- and 326 down-regulated. Salt stress also modified the expression of 54 isoforms of miRNAs in Conquista, by the maturation of 39 different pre-miRNAs. The predicted targets for 12 of those mature miRNAs also have matches with 15 differentially expressed genes from our analyses. We found genes involved in important pathways related to stress adaptation. Genes from both ABA and BR signaling pathways were modulated, with possible crosstalk between them, and with a likely post-transcriptional regulation by miRNAs. Genes related to ethylene biosynthesis, DNA repair, and plastid translation process were those that could be regulated by miRNA.
Aim
Herein we propose creating a bilayer tubular kidney in‐vitro model. It is hypothesized that membranes composed of decellularized porcine kidney extracellular matrix are valid substitutes of the ...tubular basement membrane by mimicking the physiological relevance of the in vivo environment and disease phenotypes.
Methods
Extracellular matrix was obtained from decellularized porcine kidneys. After processing by lyophilization and milling, it was dissolved in an organic solvent and blended with poly(caprolactone). Porous membranes were obtained by electrospinning and seeded with human primary renal progenitor cells to evaluate phenotypic alterations. To create a bilayer model of the in vivo tubule, the same cells were differentiated into epithelial tubular cells and co‐cultured with endothelial cells in opposite sites.
Results
Our results demonstrate increasing metabolic activity, proliferation and total protein content of renal progenitors over time. We confirmed the expression of several genes encoding epithelial transport proteins and we could also detect tubular‐specific proteins by immunofluorescence stainings. Functional and transport assays were performed trough the bilayer by quantifying both human serum albumin uptake and inulin leakage. Furthermore, we validated the chemical modulation of nephrotoxicity on this epithelium‐endothelium model by cisplatin exposure.
Conclusion
The use of decellularized matrices in combination with primary renal cells was shown to be a valuable tool for modelling renal function and disease in vitro. We successfully validated our hypothesis by replicating the physiological conditions of an in vitro tubular bilayer model. The developed system may contribute significantly for the future investigation of advanced therapies for kidney diseases.
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