Terrestrial politics and body-territory: two concepts to make sense of digital colonialism in Latin America

Researchers have argued that data colonialism is paving the way for a new stage of capitalism, defined as the result of the appropriation and trade of “datafied” human experience (Couldry and Mejias 2019). While we agree that data colonialism normalizes the exploitation of human beings through data, we also contend that the analysis of the materiality of this exploitation should be extended to both bodies and territories. There is a research gap in the literature on territorializing the Internet and rendering its power asymmetries visible. In order to advance in filling this research gap, this article reviews two concepts to make sense of the digital colonialism in Latin America. On the one hand, we discuss Latour’s concept of “terrestrial politics” (2017, 2018; Latour and Weibel 2020. On the other hand, we examine the notion of “cuerpo-territorio” (body-territories) (Cabnal 2010; Colectivo Miradas Critiques 2017) and conduct a critical dialogue between terrestrial politics and body-territory. We argue that the notion of body-territories can contribute to Latour's proposal for a terrestrial politics by rendering visible the power relationships on the territories that sustain our digital society.Estudos têm argumentado que o colonialismo de dados está abrindo caminho para uma nova etapa do capitalismo, definida como o resultado da apropriação e troca da experiência humana “datificada” (Couldry and Mejias 2019). Embora concordemos que o colonialismo digital normaliza a exploração de seres humanos por meio de dados, também defendemos que a análise da materialidade dessa exploração deve ser estendida a corpos e territórios. Há uma lacuna de pesquisa na literatura sobre a territorialização da internet e a visibilidade de suas assimetrias de poder. Para avançar potenciais contribuições teóricas que podem preencher essa lacuna na literatura, este artigo revisa dois conceitos para dar sentido ao colonialismo digital na América Latina. Por um lado, discutimos o conceito de “política terrestre” de Latour (2017, 2018; Latour and Weibel 2020). Por outro lado, examinamos a noção de “cuerpo-territorio” (Cabnal 2010; Colectivo Miradas Critiques 2017). Realizamos um diálogo crítico entre a política terrestre e o corpo-território e defendemos que a noção de corpo-território pode contribuir para a proposta de Latour de uma política terrestre ao tornar visíveis as relações de poder nos territórios que sustentam nossa sociedade digital.Se ha argumentado que el colonialismo de datos está allanando el camino para una nueva etapa del capitalismo, definida como el resultado de la apropiación y el comercio de la experiencia humana “datificada” (Couldry and Mejias 2019). Aunque estamos de acuerdo en que el colonialismo digital normaliza la explotación de los seres humanos a través de los datos, también sostenemos que el análisis de la materialidad de esta explotación debe extenderse tanto a los cuerpos como a los territorios. Existe un vacío de investigación en la literatura sobre la territorialización de internet y la visibilización de sus asimetrías de poder. Para avanzar potenciales contribuciones teóricas que puedan llenar este vacío en la literatura, este artículo revisa dos conceptos para dar sentido al colonialismo digital en América Latina. Por un lado, discutimos el concepto de “política terrestre” de Latour (2017, 2018; Latour and Weibel 2020). Por otro lado, examinamos la noción de cuerpo-territorio (Cabnal 2010; Colectivo Miradas Críticas 2017). Realizamos un diálogo crítico entre la política terrestre y el cuerpo-territorio y argumentamos que la noción de cuerpo-territorio puede contribuir a la propuesta de Latour de una política terrestre al hacer visibles las relaciones de poder en los territorios que sustentan nuestra sociedad digital

Biomaterials as Tendon and Ligament Substitutes: Current Developments

Tendon and ligament have specialized dynamic microenvironment characterized by a complex hierarchical extracellular matrix essential for tissue functionality, and responsible to be an instructive niche for resident cells. Among musculoskeletal diseases, tendon/ligament injuries often result in pain, substantial tissue morbidity, and disability, affecting athletes, active working people and elder population. This represents not only a major healthcare problem but it implies considerable social and economic hurdles. Current treatments are based on the replacement and/or augmentation of the damaged tissue with severe associated limitations. Thus, it is evident the clinical challenge and emergent need to recreate native tissue features and regenerate damaged tissues. In this context, the design and development of anisotropic bioengineered systems with potential to recapitulate the hierarchical architecture and organization of tendons and ligaments from nano to macro scale will be discussed in this chapter. Special attention will be given to the state-of-the-art fabrication techniques, namely spinning and electrochemical alignment techniques to address the demanding requirements for tendon substitutes, particularly concerning the importance of biomechanical and structural cues of these tissues. Moreover, the poor innate regeneration ability related to the low cellularity and vascularization of tendons and ligaments also anticipates the importance of cell based strategies, particularly on the stem cells role for the success of tissue engineered therapies. In summary, this chapter provides a general overview on tendon and ligaments physiology and current conventional treatments for injuries caused by trauma and/or disease. Moreover, this chapter presents tissue engineering approaches as an alternative to overcome the limitations of current therapies, focusing on the discussion about scaffolds design for tissue substitutes to meet the regenerative medicine challenges towards the functional restoration of damaged or degenerated tendon and ligament tissues.Portuguese Foundation for Science and Technology for the post-doctoral grant (SFRH/BPD/111729/2015) and for the projects Recognize (UTAP-ICDT/CTM-BIO/0023/2014) and POC I-01-0145-FEDER-007

Cryopreservation of cell laden natural origin hydrogels for cartilage regeneration strategies

Statement of Purpose: An increase of scientific published literature and clinical experience supports the requirement of providing products like cultured cells and tissues to the market. One of the main prospects of cartilage tissue engineering is the possibility of developing custom-made regenerative medicine solutions on an individual patient basis. The efficient preservation and storage procedure will provide products available as needed which could be adapted to an autologous immediate solution. Thus, the aim of this study was to examine the effects of the cryopreservation on the chondrogenic differentiation characteristics of human mesenchymal stem cells isolated from adipose tissue (hASCs). Furthermore, we also propose to determine hASCs-hydrogel stability and confirm the potential of these bioengineered constructs to be applied in cartilage regeneration. The results obtained show that the hydrogels withstand the cryopreservation process maintaining their structural integrity, with good cell content after cryopreservation. Thus, cell encapsulation systems of natural based hydrogels may be an interesting approach for the long term preservation of cartilage tissue engineered products. Methods: The κ-carrageenan (κCR) hydrogels were produced using an ionotropic gelation method. Then, stem cells, namely human adipose derived stem cells (hASCs), were encapsulated in κCR discs (5 mm dia. x 3 mm height) at a density of 5x106 cell/cm3 and cultured for 21 days in standard basal (BM) or chondrogenic media (ChM). The cell hydrogels were cryopreserved in liquid nitrogen for up to 30 days. The overall morphology of κCR discs with encapsulated hASCs was observed under light microscope. hASCs viability and proliferation rate was determined by double stand DNA quantification. Additionally, chondrogenic differentiation of hASCs encapsulated in the hydrogels is being characterized by histological staining for selective cartilage staining and real time PCR analysis (Sox9, aggrecan, and collagen: type I, type II and type X). DMA analysis allowed determining the mechanical properties of κ-carrageenan hydrogels, namely storage (elastic) and loss (viscous) while immersed in wet state at 24 °C and throughout a physiological relevant range of frequencies. The described characterization assays were performed both before (BC) and after cryopreservation/freezing (AC) time points. Results: The cell morphology, distribution and appearance of the hydrogels are clearly observed from the microscopic light images (Figure 1A). It is possible to observe the smooth and homogeneous surface, the well defined and stable shape before and after the freezing process. Encapsulated hASCs were able to maintain cellular content, despite an expected decrease observed upon cryopreservation (Figure 1B), which is associated to a recovery time after thawing. The microscopic images and biological evaluation of κCR hydrogel revealed that the cryopreservation process did not change the cellular morphology; the surface and integrity of the hydrogel disc and enables maintenance of hASCs after exposure to low temperatures environments. Figure 1. (A) Representative optical micrographs of hASCs encapsulated in κCR hydrogels and cultured in ChM and BM before and after cryopreservation and (B) cell proliferation results, based on the quantification of dsDNA content. Scale bar represent 100 μm. Conclusions: The results obtained so far indicated the feasibility of hASCs-κCR system in cartilage tissue engineering regeneration strategies due to its ability to support hASCs viability before and after cryopreservation. Ongoing studies on the assessment of chondrogenic features of these cryopreserved systems will provide information on the effect of cryopreservation indicative of a stable chondrocyte phenotype. In summary, this study provided information on the potential of ASCs-hydrogel constructs for a long term storage and ready to use bioengineered tissue substitutes for cartilage regeneration strategies. References: (Popa EG. Biomacromolecules 2011;12:3952-3961

Development of new chitosan/carrageenan nanoparticles for drug delivery applications

The use of polymeric nanoparticles, especially those composed of natural polymers, has become a very interesting approach in drug delivery., mainly because of the advantages offered by their small dimensions. The aim of this work was to develop a novel formulation of nanoparticles comprised of two natural marine-derived polymers, namely chitosan and carrageenan, and to evaluate their potential for the association and controlled release of macromolecules. Nanoparticles were obtained in a hydrophilic environment, under very mild conditions, avoiding the use of organic solvents or other aggressive technologies for their preparation. The developed nanocarriers presented sizes within 350-650 run and positive zeta potentials of 50-60 mV. Polymeric interactions between nanoparticles' components were evaluated by Fourier transform infrared spectroscopy. Using ovalbumin as model protein, nanoparticles evidenced loading capacity varying from 4% to 17%, and demonstrated excellent capacity to provide a controlled release for up to 3 weeks. Furthermore, nanoparticles have demonstrated to exhibit a noncytotoxic behavior in biological in vitro tests performed using L929 fibroblasts, which is critical regarding the biocompatibility of those carriers. In summary, the developed chitosan-carrageenan nanoparticles have shown promising properties to be used as carriers of therapeutic macromolecules, with potential application not only strictly in drug delivery, but also in broader areas, such as tissue engineering and regenerative medicine. (C) 2009 Wiley Periodicals, Inc. J Biomed Mater Res 92A: 1265-1272, 2010Contract grant sponsor: Portuguese Foundation for Science and Technology (FCT) (POCTI/FEDER programmes)Contract grant sponsor: European Union STREP Project HIPPOCRATES; contract grant number: NMP3-CT-2003505758Contract grant sponsor: European NoE EXPERTISSUES; contract grant number: NMP3-CT-2004-50028

Hemoglobinopatias no Distrito Federal, Brasil

Em uma amostra de 3137 pessoas, residentes no Distrito Federal, foram detectadas as seguintes hemoglobinas: em 3009(95,92%) HbAA; em 91 (2,90%) HbAS; em 20(0,64%) HbAC; em 8 (0,26%) talassemia beta minor; em 5(0,16%) HbAJ alfa; em 3 (0,09%) HbAM e em 1 (0,03%) talassemia major associada com HbAS. A HbAS têm as seguintes freqüências, quanto ao grupo racial: branco - 1,84%; mulato claro 2,55%; mulato médio-3,68%; mulato escuro - 6,80%; negro -10,43% e mestiço de índio -3,85%.The hemoglobins of 3137 persons from the Federal District, Brazil was studied. The identified types of hemoglobins were: HbAA (3009 - 95,92%); HbAS (91 - 2,90%); HbAC (20 - 0,64%) beta thalassemia minor (8 - 0,26%); HbAJ alpha (5 - 0,16%); HbAM (3 - 0,09%) and beta thalassemia major/HbS (1 - 0,03%). The frequencies of sickle cell trait (HbAS) of each racial class were: white (1,84%); light mulatto (2,55%); medium mulatto (3,68%); dark mulatto(6,80%), negro (10,43%)and indian mestizo (3,85%)

Novel genipin cross-linked chitosan-silk fibroin sponges for cartilage engineering strategies

The positive interaction of materials with tissues is an important step in regenerative medicine strategies. Hydrogels that are obtained from polysaccharides and proteins are expected to mimic the natural cartilage environment and thus provide an optimum milleu for tissue growth and regeneration. In this work, novel hydrogels composed of blends of chitosan and Bombyx mori silk fibroin were cross-linked with genipin (G) and were freeze dried to obtain chitosan/silk (CSG) sponges. CSG sponges possess stable and ordered structures because of protein conformational changes from R-helix/random-coil to -sheet structure, distinct surface morphologies, and pH/ swelling dependence at pH 3, 7.4, and 9. We investigated the cytotoxicity of CSG sponge extracts by using L929 fibroblast-like cells. Furthermore, we cultured ATDC5 cells onto the sponges to evaluate the CSG sponges’ potential in cartilage repair strategies. These novel sponges promoted adhesion, proliferation, and matrix production of chondrocyte-like cells. Sponges’ intrinsic properties and biological results suggest that CSG sponges may be potential candidates for cartilage tissue engineering (TE) strategies.S.S.S. and M.T.R. thank the Portuguese Foundation for Science and Technology (FCT) for Ph.D. scholarships (SFRH/BD/8658/2002 and SFRH/BD/30745/2006, respectively). A.F.M.P. thanks the FCT and FEDER for a grant (POCI/FIS/61621/2004). This work was partially supported by the European-Union-funded STREP project HIPPOCRATES (NMP3-CT-2003-505758) and was carried out under the scope of the European NoE EXPERTISSUES (NMP3-CT-2004-500283). We also acknowledge Adriano Pedro for his contribution to the micro-CT analysis

Previous exercise training increases levels of PPAR-α in long-term post-myocardial infarction in rats, which is correlated with better inflammatory response

OBJECTIVE: Exercise is a protective factor for cardiovascular morbidity and mortality, with unclear mechanisms. Changing the myocardial metabolism causes harmful consequences for heart function and exercise contributes to metabolic adjustment modulation. Peroxisome proliferator-activated receptors (PPARs) are also myocardium metabolism regulators capable of decreasing the inflammatory response. We hypothesized that PPAR-α is involved in the beneficial effects of previous exercise on myocardial infarction (MI) and cardiac function, changing the expression of metabolic and inflammatory response regulators and reducing myocardial apoptosis, which partially explains the better outcome. METHODS AND RESULTS: Exercised rats engaged in swimming sessions for 60 min/day, 5 days/week, for 8 weeks. Both the exercised rats and sedentary rats were randomized to MI surgery and followed for 1 week (EI1 or SI1) or 4 weeks (EI4 or SI4) of healing or to sham groups. Echocardiography was employed to detect left ventricular function and the infarct size. Additionally, the TUNEL technique was used to assess apoptosis and immunohistochemistry was used to quantitatively analyze the PPAR-α, TNF-α and NF-κB antigens in the infarcted and non-infarcted myocardium. MI-related mortality was higher in SI4 than in EI4 (25% vs 12%), without a difference in MI size. SI4 exhibited a lower shortening fraction than EI4 did (24% vs 35%) and a higher apoptosis/area rate (3.97±0.61 vs 1.90±1.82) in infarcted areas (both p=0.001). Immunohistochemistry also revealed higher TNF-α levels in SI1 than in EI1 (9.59 vs 4.09,

T-box transcription factor Brachyury is associated with prostate cancer progression and aggressiveness

Purpose: Successful therapy of patients with prostate cancer is highly dependent on reliable diagnostic and prognostic biomarkers. Brachyury is considered a negative prognostic factor in colon and lung cancer; however, there are no reports on Brachyury’s expression in prostate cancer. Experimental Design: In this study, we aimed to assess the impact of Brachyury expression in prostate tumorigenesis using a large series of human prostate samples comprising benign tissue, prostate intraepithelial neoplasia (PIN) lesions, localized tumor, and metastatic tissues. The results obtained were compared with what can be inferred from the Oncomine database. In addition, multiple in vitro models of prostate cancer were used to dissect the biologic role of Brachyury in prostate cancer progression. Results: We found that Brachyury is significantly overexpressed in prostate cancer and metastatic tumors when compared with normal tissues, both at protein and at mRNA levels. Brachyury expression in the cytoplasm correlates with highly aggressive tumors, whereas the presence of Brachyury in the nucleus is correlated with tumor invasion. We found that Brachyury-positive cells present higher viability, proliferation, migration, and invasion rates than Brachyury-negative cells. Microarray analysis further showed that genes co-expressed with Brachyury are clustered in oncogenic-related pathways, namely cell motility, cellcycle regulation, and cell metabolism. Conclusions: Collectively, the present study suggests that Brachyury plays an important role in prostate cancer aggressiveness and points, for the first time, to Brachyury as a significant predictor of poor prostate cancer prognosis. Our work paves the way for future studies assessing Brachyury as a possible prostate cancer therapeutic target.This study was supported by the ICVS internal research funds of participating authors and by the FCT project, ref. PTDC/SAU-MET113415/2009. F. Pinto and N. Pertega-Gomes received fellowships from the FCT, ref. SFRH/BD/81369/2011 and SFRH/BD/61027/2009, respectively. R. P. Andrade was funded by Ciencia2007 Program Contract and Programa Operacional Regional do Norte (ON. 2) - NORTE-07-0124-FEDER-000017

Long noncoding intronic RNAs are differentially expressed in primary and metastatic pancreatic cancer

<p>Abstract</p> <p>Background</p> <p>Pancreatic ductal adenocarcinoma (PDAC) is known by its aggressiveness and lack of effective therapeutic options. Thus, improvement in current knowledge of molecular changes associated with pancreatic cancer is urgently needed to explore novel venues of diagnostics and treatment of this dismal disease. While there is mounting evidence that long noncoding RNAs (lncRNAs) transcribed from intronic and intergenic regions of the human genome may play different roles in the regulation of gene expression in normal and cancer cells, their expression pattern and biological relevance in pancreatic cancer is currently unknown. In the present work we investigated the relative abundance of a collection of lncRNAs in patients' pancreatic tissue samples aiming at identifying gene expression profiles correlated to pancreatic cancer and metastasis.</p> <p>Methods</p> <p>Custom 3,355-element spotted cDNA microarray interrogating protein-coding genes and putative lncRNA were used to obtain expression profiles from 38 clinical samples of tumor and non-tumor pancreatic tissues. Bioinformatics analyses were performed to characterize structure and conservation of lncRNAs expressed in pancreatic tissues, as well as to identify expression signatures correlated to tissue histology. Strand-specific reverse transcription followed by PCR and qRT-PCR were employed to determine strandedness of lncRNAs and to validate microarray results, respectively.</p> <p>Results</p> <p>We show that subsets of intronic/intergenic lncRNAs are expressed across tumor and non-tumor pancreatic tissue samples. Enrichment of promoter-associated chromatin marks and over-representation of conserved DNA elements and stable secondary structure predictions suggest that these transcripts are generated from independent transcriptional units and that at least a fraction is under evolutionary selection, and thus potentially functional.</p> <p>Statistically significant expression signatures comprising protein-coding mRNAs and lncRNAs that correlate to PDAC or to pancreatic cancer metastasis were identified. Interestingly, <it>loci </it>harboring intronic lncRNAs differentially expressed in PDAC metastases were enriched in genes associated to the MAPK pathway. Orientation-specific RT-PCR documented that intronic transcripts are expressed in sense, antisense or both orientations relative to protein-coding mRNAs. Differential expression of a subset of intronic lncRNAs (<it>PPP3CB</it>, <it>MAP3K14 </it>and <it>DAPK1 loci</it>) in metastatic samples was confirmed by Real-Time PCR.</p> <p>Conclusion</p> <p>Our findings reveal sets of intronic lncRNAs expressed in pancreatic tissues whose abundance is correlated to PDAC or metastasis, thus pointing to the potential relevance of this class of transcripts in biological processes related to malignant transformation and metastasis in pancreatic cancer.</p