The advent of organic farming models: analysis of the current situation and perspectives in Brazil.

This text analyses the development of organic farming in Brazil. It shows the great variability of social models of organic production recognised by Brazilian Law: organic, agroecological, ecological or biodynamic agriculture, permaculture etc.. It depicts how the political and social concerns in the spheres of family farming and environment caused the reorganisation of production systems, in the agricultural practices and n the new relationships with the market and with natural resources. Based on interviews with farmers and stakeholders involved in the development of various organic systems, we qualified the related models of production as well as the related social and cultural values. We also present some aspects of the historical roots of this agroecological movement and the way family farmers adapt to the new challenges of ecological production

Generation of a human iPS cell line from a patient with retinitis pigmentosa due to EYS mutation

Retinitis pigmentosa (RP) is an inherited retinal degenerative disease. Mutations in EYS have been associated with autosomal recessive RP. The human iPS cell line, CABi002-A, derived from peripheral blood mononuclear cells from a patient carrying a heterozygous double mutation in EYS gene was generated by non-integrative reprogramming technology, using hOCT3/4, hSOX2, hc-MYC and hKLF4 reprogramming factors. Pluripotency and differentiation capacity were assessed by immunocytochemistry and RT-PCR. This iPSC line can be further differentiated towards the affected cells to understand the pathophysiology of the disease and test new therapeutic strategies.Cellex FoundationFundación Progreso y Salu

Taming Cell-to-Cell Heterogeneity in Acute Myeloid Leukaemia With Machine Learning.

Acute Myeloid Leukaemia (AML) is a phenotypically and genetically heterogenous blood cancer characterised by very poor prognosis, with disease relapse being the primary cause of treatment failure. AML heterogeneity arise from different genetic and non-genetic sources, including its proposed hierarchical structure, with leukemic stem cells (LSCs) and progenitors giving origin to a variety of more mature leukemic subsets. Recent advances in single-cell molecular and phenotypic profiling have highlighted the intra and inter-patient heterogeneous nature of AML, which has so far limited the success of cell-based immunotherapy approaches against single targets. Machine Learning (ML) can be uniquely used to find non-trivial patterns from high-dimensional datasets and identify rare sub-populations. Here we review some recent ML tools that applied to single-cell data could help disentangle cell heterogeneity in AML by identifying distinct core molecular signatures of leukemic cell subsets. We discuss the advantages and limitations of unsupervised and supervised ML approaches to cluster and classify cell populations in AML, for the identification of biomarkers and the design of personalised therapies

The Role of SepF in Cell Division and Diazotrophic Growth in the Multicellular Cyanobacterium Anabaena sp. Strain PCC 7120

The cyanobacterium Anabaena forms filaments of cells that grow by intercalary cell division producing adjoined daughter cells connected by septal junction protein complexes that provide filament cohesion and intercellular communication, representing a genuine case of bacterial multicellularity. In spite of their diderm character, cyanobacterial genomes encode homologs of SepF, a protein normally found in Gram-positive bacteria. In Anabaena, SepF is an essential protein that localized to the cell division ring and the intercellular septa. Overexpression of sepF had detrimental effects on growth, provoking conspicuous alterations in cell morphology that resemble the phenotype of mutants impaired in cell division, and altered the localization of the division-ring. SepF interacted with FtsZ and with the essential FtsZ tether ZipN. Whereas SepF from unicellular bacteria generally induces the bundling of FtsZ filaments, Anabaena SepF inhibited FtsZ bundling, reducing the thickness of the toroidal aggregates formed by FtsZ alone and eventually preventing FtsZ polymerization. Thus, in Anabaena SepF appears to have an essential role in cell division by limiting the polymerization of FtsZ to allow the correct formation and localization of the Z-ring. Expression of sepF is downregulated during heterocyst differentiation, likely contributing to the inhibition of Z-ring formation in heterocysts. Finally, the localization of SepF in intercellular septa and its interaction with the septal-junction related proteins SepJ and SepI suggest a role of SepF in the formation or stability of the septal complexes that mediate cell-cell adhesion and communication, processes that are key for the multicellular behavior of Anabaena.Ministerio de Ciencia e Innovación PID2020-118595GB-10

Synthesis and characterization of polymeric nanoparticles and their application in anticancer therapy

Motivation: Traditional and current chemotherapy used to treat cancer disease has always been characterized by the high prevalence of side effects. In order to avoid them, nanotechnology has raised as an acceptable solution to this problem by selectively targeting anticancer drugs to the tumoral cells. Within this project to antitumoral agents, tannic acid and amitriptyline, have been encapsulated in polymeric nanoparticles to allow their targeted delivery. Amitriptyline is a tricyclic antidepressant whose antitumoral activity against lung cancer was recently described [1], and this agent could be a good approach for treating other tumoral diseases.Methods: Tannic acid nanoparticles (TA) were synthetized according to a method previously described by our group [2], and PLGA-amitriptyline nanoparticles (PLGAMI) by emulsion solvent evaporation method. The so-obtained nanoparticles were characterized by dynamic light scattering (DLS), scanning electron microscopy (SEM) and FTIR spectroscopy.Results: Both nanoparticles, TA and PLGAMI, are small and spherical. TA nanoparticles showed a mean diameter of 60 nm (SEM), a hydrodynamic diameter of 500 nm and a zeta potential of -22 mV (DLS). PLGAMI nanoparticles showed a mean diameter of 25 nm, a hydrodynamic diameter of 110 nm and a zeta potential of -8 mV. The presence of the antitumoral agents in nanoparticles was confirmed by FTIR spectroscopy, and the entrapment efficiency determined by colorimetric methods, using an UV-Vis spectroscope.Conclusions: We have synthetized two polymeric nanoparticles bearing antitumoral agents as cargo. Our data confirm that these nanoparticles are suitable for continuing with the in-vitro assays, where we will compare the pro-apoptotic effect of both nanoparticles in cell cultures (H460 tumor cell line)

Diet quality, food groups and nutrients associated with the gut microbiota in a nonwestern population

Diet plays an important role in shaping gut microbiota. However, much remains to be learned regarding this association. We analyzed dietary intake and gut microbiota in a community-dwelling cohort of 441 Colombians. Diet quality, intake of food groups and nutrient consumption were paired with microbial diversity and composition using linear regressions, Procrustes analyses and a random-forest machine-learning algorithm. Analyses were adjusted for potential confounders, including the five cities from where the participants originated, sex (male, female), age group (18-40 and 41-62 years), BMI (lean, overweight, obese) and socioeconomic status. Microbial diversity was higher in individuals with increased intake of nutrients obtained from plant-food sources, whereas the intake of food groups and nutrients correlated with microbiota structure. Random-forest regressions identified microbial communities associated with different diet components. Two remarkable results confirmed previous expectations regarding the link between diet and microbiota: communities composed of short-chain fatty acid (SCFA) producers were more prevalent in the microbiota of individuals consuming diets rich in fiber and plant-food sources, such as fruits, vegetables and beans. In contrast, an inflammatory microbiota composed of bile-tolerant and putrefactive microorganisms along with opportunistic pathogens thrived in individuals consuming diets enriched in animal-food sources and of low quality, i.e., enriched in ultraprocessed foods and depleted in dietary fiber. This study expands our understanding of the relationship between dietary intake and gut microbiota. We provide evidence that diet is strongly associated with the gut microbial community and highlight generalizable connections between them