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The article presents an overview of some theoretical discussions related to the way in which public state television faces digital convergence. From the perspective of the Political Economy of Communication (PEC), the work takes up some classic and current problems of the PEC agenda, such as communicational concentration, the platform economy and the democratization of communication. With these tools, it seeks to carry out a situated analysis of the possibilities of development of public television in the face of convergence, in peripheral contexts. [ABSTRACT FROM AUTHOR]

This article analyzes how the ownership structure and the alliances between the agents producing serialized fiction for television are linked to the themes and narratives addressed by this type of cultural product. From the political economy of communication and cultural studies, the paper examines the predominant themes in the 100 most watched premiere fictions on open television in Argentina during the decade between 2011 and 2020. It is concluded that there is a wide predominance of universal themes with nonstructural local references, over purely local ones. [ABSTRACT FROM AUTHOR]

This work presents a state of the art with the main theoretical discussions regarding the distribution of audiovisual content on the internet from peripheral contexts. The text covers the main problems of the digital economy, in particular the situation of high concentration and dominance of few global agents that design and conduct the online content distribution processes. The main argument is illustrated from El Marginal, a public funded TV series, distributed globally through Netflix, which implied the subordination of the public service function to a commercial logic. [ABSTRACT FROM AUTHOR]

This article aims to study how the ownership structure of the media system and the role of the State are linked to the deterioration of journalistic work and the exercise of freedom of speech. From the Political Economy of Journalism and the discussions on the right to information, a comparative study is proposed to contrast the situation in Brazil, Argentina and Chile between 2016 and 2018. It is concluded that the high concentration in the three media systems, along with the retraction of the State as regulator and content producer, deepen a crisis that threatens journalistic activity. [ABSTRACT FROM AUTHOR]

Aims: Breast cancer is the most frequently diagnosed and leading cause of cancer death among women worldwide. It was classified within molecular intrinsic subtypes: luminal A, luminal B, human epidermal growth factor receptor 2‐enriched and basal‐like. Epinephrine and norepinephrine, released during stress, bind to adrenoceptors. α2‐adrenoceptors are encoded by the ADRA2A, ADRA2B and ADRA2C genes and β2 by ADRB2. Methods: We compiled several publicly available Affymetrix gene expression datasets, obtaining a large cohort of 1924 patients with distant metastasis‐free survival (DMFS) data and evaluated the association between adrenoceptor expression, clinicopathological markers and outcome. Results: ADRA2A high expressing tumours also expressed hormone receptors and presented diminished tumour size, grade and not compromised lymph nodes. ADRB2 high expression was found in smaller, low grade, oestrogen receptor‐positive tumours. Both were significantly associated with the absence of metastasis. High expression of ADRA2C was positively associated with increased tumour size and metastatic relapse. We observed a significant increase in DMFS of patients with high ADRA2A (hazard ratio 0.54, 95% CI 0.45–0.65, P <.001) and ADRB2 (0.77, 0.64–0.93, P =.006) expression and a decrease with ADRA2C high expression (1.45, 1.16–1.81, P =.001). For patients with luminal tumours, ADRA2A was the only factor that retained its significance as an independent predictor of DMFS while ADRA2C expression was an independent predictor for worse prognosis in basal‐like tumours. Conclusions: We herein provide new insight for a potential role of ADRA2A and ADRA2C in breast cancer. In low‐ and medium‐income countries, their incorporation to routine immunohistochemistry analysis of biopsies or tumour samples, could provide additional low‐cost prognostic factors. [ABSTRACT FROM AUTHOR]

Purpose: Globally breast cancer accounts for 24.5% in incidence and 15.5% in cancer deaths in women. The triple-negative subtype lacks any specific therapy and is treated with chemotherapy, resulting in significant side-effects. We aimed to investigate if the dose of chemotherapeutic drugs could be diminished by co-administering it with the β2-agonist salbutamol. Methods: Cell proliferation was measured by thymidine incorporation; gene expression, by real-time PCR and protein phosphorylation by WB. Apoptosis was assessed by acridine orange / ethidium bromide and TUNEL tests. Public patient databases were consulted. Cells were inoculated to nude mice and their growth assessed. Results: The β2-agonist salbutamol synergizes in MDA-MB-231 cells in vitro with paclitaxel and doxorubicin on cell proliferation through ADRB2 receptors, while the β-blocker propranolol does not. The expression of this receptor was assessed in patient databases and other cell lines. Triple negative samples had the lowest expression. Salbutamol and paclitaxel decreased MDA-MB-231 cell proliferation while their combination further inhibited it. The pathways involved were analyzed. When these cells were inoculated to nude mice, paclitaxel and salbutamol inhibited tumor growth. The combined effect was significantly greater. Paclitaxel increased the expression of MDR1 while salbutamol partially reversed this increase. Conclusion: While the effect of salbutamol was mainly on cell proliferation, suboptimal concentrations of paclitaxel provoked a very important enhancement of apoptosis. The latter enhanced transporter proteins as MDR1, whose expression were diminished by salbutamol. The expression of ADRB2 should be assessed in the biopsy or tumor to eventually select patients that could benefit from salbutamol repurposing. [ABSTRACT FROM AUTHOR]

Breast cancer is the most frequent malignancy among women worldwide. We have described the expression of α 2 -adrenoceptors in breast cancer cell lines, associated with increased cell proliferation and tumor growth. A mitogenic autocrine/paracrine loop of prolactin (Prl) has been described in breast cancer cells. We hypothesized that the α 2 -adrenergic enhancement of proliferation could be mediated, at least in part, by this Prl loop. In both T47D and MCF-7 cell lines, the incubation with the α 2 -adrenergic agonist dexmedetomidine significantly increased Prl release into the culture medium (measured by the Nb2 bioassay), this effect being reversed by the α 2 -adrenergic antagonist rauwolscine. No change in Prl receptors (PrlR) was observed by RT-qPCR in these cell lines. In IBH-6 cells a decrease in Prl secretion was observed at the lower dexmedetomidine concentration. The signaling pathways involved in ovine Prl (oPrl) and dexmedetomidine action were also assessed. Both compounds significantly activated STAT5 and ERK in all three cell lines. In T47D and MCF-7 cell lines also AKT was activated by both Prl and dexmedetomidine. We therefore describe the STAT5 phosphorylation by an α 2 -adrenergic agonist, dexmedetomidine. In T47D cells, the α 2 -adrenergic stimulation of cell proliferation is probably mediated, at least in part, by the Prl autocrine/paracrine loop, because this effect is abrogated by the specific PrlR antagonist Δ1–9-G129R-hPrl. The implication of Prl loop describes a novel mechanism of action of this GPCR. [ABSTRACT FROM AUTHOR]

The relation between intellectuals and the elaboration of public policies present multiple nuances and it can be dealt with different approaches within social sciences. In this text, we specifically analyze the interventions of these actors in academic meetings and discussions organized by the argentine government towards a law which will regulate media and telecommunications in a unifying way. In the process, we will show cuts in subject matters and stages for the debate, exclusions and the sense of experts' contributions at a moment marked by new and controversial policies in the country. [ABSTRACT FROM AUTHOR]

Abstract: The antiestrogenic activity of three natural salpichrolides A, G and B (1, 3 and 4) and of five synthetic analogs containing an aromatic D ring and a simplified side chain (5–9), was evaluated on MCF-7 cells. The 2,3-ene-1-keto steroids 8 and 9 were obtained from 3β-acetoxy-17(13→18)-abeo-5αH-pregna-13,15,17-trien-20-one, the key step for these syntheses being a Wharton carbonyl rearrangement of a 1,2-epoxy-3-keto steroid to the allylic alcohol using hydrazine hydrate. The antiestrogenic activity was evaluated by performing dose–response experiments in ER(+) MCF-7 breast cancer cells. Dose-dependent proliferation was quantified via [3H]-thymidine incorporation after 3 days treatment. Salpichrolides A, G and B and analogs 5, 8 and 9 were active as antiestrogens with compound 9 being the most active of the synthetic analogs. Compounds 5 and 9 were also evaluated against the ER(−) cell line MDA-MB-231 and shown to be inactive. [Copyright &y& Elsevier]

The β-blocker propranolol (PROP) has been proposed as a repurposed treatment for breast cancer. The similarity of action between β-agonists and antagonists found on breast cells encouraged us to compare PROP and isoproterenol (ISO, agonist) signaling pathways on a human breast cell line. Cell proliferation was measured by cell counting and DNA-synthesis. Cell adhesion was measured counting the cells that remained adhered to the plastic after different treatments. Changes in actin cytoskeleton were observed by fluorescence staining and Western Blot. ISO and PROP caused a diminution of cell proliferation and an increase of cell adhesion, reverted by the pure β-antagonist ICI-118551. ISO and PROP induced a reorganization of actin cytoskeleton increasing F-actin, p-COFILIN and p-LIMK. While ISO elicited a marked enhancement of cAMP concentrations and an increase of vasodilator-stimulated phosphoprotein (VASP) and cAMP response element-binding protein (CREB) phosphorylation, PROP did not. Clathrin-mediated endocytosis inhibition or β-arrestin1 dominant-negative mutant abrogated PROP-induced cell adhesion and COFILIN phosphorylation. The fact that PROP has been proposed as an adjuvant drug for breast cancer makes it necessary to determine the specific action of PROP in breast models. These results provide an explanation for the discrepancies observed between experimental results and clinical evidence. [ABSTRACT FROM AUTHOR]

Our paper analyzes the public media policies developed in Argentina since December 2015, in a context characterized by regulatory changes around the expanded audiovisual sector and by an intervention in the management of Public TV, which affected the institutional structure of the oldest television station in the country and canceled the renovation in the last decade in the framework of which there was a growth of audiences and a renewal of the aesthetics of this screen. To do so, we take into account the changes that occurred in three variables: institutional architecture, financing and channel programming policies. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the effect of repeated traffic with a light-weight tractor on the physical/mechanical properties of an Aridisol soil from eastern Almería (Spain). The soil has been used for almond (Prunus amigdalus L.) production for the past 29 years. A light modal tractor (≈15 kN overall load) and different traffic frequencies or treatments; namely, 0 (control, no traffic), and 1, 5, 7, and 10 passes, respectively, were used. The following variables were measured: cone Index (CI); bulk density (BD); total soil porosity (TSP); water infiltration into soil (I), and ruth depth (RD). The results showed that, only treatments 7 and 10 led to significant increases in CI and BD throughout the soil profile (0-450 mm). Changes in TSP in those treatments were consistent with changes in soil bulk density. No significant differences in RD were found when the tractor passed 1 or 5 times. All traffic treatments resulted in significant compaction in the topsoil layer (0-150 mm) and soil physical conditions that would be regarded as unsuitable for establishment of most arable crops. [ABSTRACT FROM AUTHOR]

In this work, we quantified the effects of harvest traffic having different tyre ground pressures and axle loads on soil properties and maize (Zea Mays L.) yields. The treatments consisted of a control plot with no traffic (T1), a combine harvester with low tyre ground pressure (T2) and the same harvest traffic with high tyre ground pressure (T3). Cone index (CI), soil water content (SWC), rut depth (RD), root dry matter per plant (RDM) and maize yields (MY) were measured at seven places in relation to the tracks, namely: centre of the tracks (0), and at 70, 140 and 210 cm on either side of them. For three growing seasons, the results showed that in the topsoil (0 to 20 cm), CI values produced by treatment T3 were > 2.7 MPa and between 3.4 to 4.25 MPa in the subsoil (20 to 60 cm). Also, when the soil was trafficked by tyres with infaltion pressures of 120 to 240 kPa, the CI increased in the topsoil and subsoil, but differences in rut depth (RD) at the surface did not extend into the subsoil in terms of CI. The greatest differences in RDM were found in the third growing season. The minimum MY of 4.7 Mg ha-1 was observed in 2016 (third growing season) in the centre line of the tyre tracks after one pass of combine harvester with high tyre ground pressure. Yield increased with distance from the track centres reaching 5.10 Mg ha-1 at 210 cm on either side of them. The main conclusions were that one pass of the combine harvesters with total weight load between 16.67 and 21.10 Mg was sufficient to increase the CI in both the topsoil and subsoil layers while maize yields were significantly reduced by all compaction in the combine harvesters tracks, as well as all positions alongside them. [ABSTRACT FROM AUTHOR]

Treatment of retinoblastoma -a pediatric cancer of the developing retina- might benefit from strategies to inhibit the blood-retinal barrier (BRB). The potent anticancer agent topotecan is a substrate of efflux transporters BCRP and P-gp, which are expressed at the BRB to restrict vitreous and retinal distribution of xenobiotics. In this work we have studied vitreous and retinal distribution, tumor accumulation and antitumor activity of topotecan, using pantoprazole as inhibitor of BCRP and P-gp. We used rabbit and mouse eyes as BRB models and patient-derived xenografts as retinoblastoma models. To validate the rabbit BRB model we stained BCRP and P-gp in the retinal vessels. Using intravitreous microdialysis we showed that the penetration of the rabbit vitreous by lactone topotecan increased significantly upon concomitant administration of pantoprazole (P = 0.0285). Pantoprazole also increased topotecan penetration of the mouse vitreous, measured as the vitreous-to-plasma topotecan concentration ratio at the steady state (P = 0.0246). Pantoprazole increased topotecan antitumor efficacy and intracellular penetration in retinoblastoma in vitro , but did not enhance intratumor drug distribution and survival in mice bearing the intraocular human tumor HSJD-RBT-2. Anatomical differences with the clinical setting likely limited our in vivo study, since xenografts were poorly vascularized masses that loaded most of the vitreous compartment. We conclude that pharmacological modulation of the BRB is feasible, enhances anticancer drug distribution into the vitreous and might have clinical implications in retinoblastoma. Chemical compounds included in this manuscript Topotecan (PubChem CID: 60700) Pantoprazole sodium (PubChem CID: 15008962) [ABSTRACT FROM AUTHOR]

Understanding the mechanisms that govern normal mammary gland development is crucial to the comprehension of breast cancer etiology. β-adrenergic receptors (β-AR) are targets of endogenous catecholamines such as epinephrine that have gained importance in the context of cancer biology. Differences in β-AR expression levels may be responsible for the effects of epinephrine on tumor vs non-tumorigenic breast cell lines, the latter expressing higher levels of β-AR. To study regulation of the breast cell phenotype by β-AR, we over-expressed β-AR in MCF-7 breast cancer cells and knocked-down the receptor in non-tumorigenic MCF-10A breast cells. In MCF-10A cells having knocked-down β-AR, epinephrine increased cell proliferation and migration, similar to the response by tumor cells. In contrast, in MCF-7 cells overexpressing the β-AR, epinephrine decreased cell proliferation and migration and increased adhesion, mimicking the response of the non-tumorigenic MCF-10A cells, thus underscoring that β-AR expression level is a key player in cell behavior. β-adrenergic stimulation with isoproterenol induced differentiation of breast cells growing in 3-dimension cell culture, and also the branching of murine mammary epithelium in vivo. Branching induced by isoproterenol was abolished in fulvestrant or tamoxifen-treated mice, demonstrating that the effect of β-adrenergic stimulation on branching is dependent on the estrogen receptor (ER). An ER-independent effect of isoproterenol on lumen architecture was nonetheless found. Isoproterenol significantly increased the expression of ERα, Ephrine-B1 and fibroblast growth factors in the mammary glands of mice, and in MCF-10A cells. In a poorly differentiated murine ductal carcinoma, isoproterenol also decreased tumor growth and induced tumor differentiation. This study highlights that catecholamines, through β-AR activation, seem to be involved in mammary gland development, inducing mature duct formation. Additionally, this differentiating effect could be resourceful in a breast tumor context. [ABSTRACT FROM AUTHOR]