Adsorption and mobility of glyphosate in different soils under no-till and conventional tillage Okada, Elena; Costa, Jose Luis; Bedmar, Francisco Glyphosate (N-(phosphonomethyl) glycine) is a post-emergence, non-selective, foliar herbicide. Around 200 million. liters of this herbicide are applied every year in Argentina, where the main agricultural practice is no-till (NT), accounting for 78.5% of the cultivated land. In this work, we studied the adsorption of glyphosate in different soils under long-term management (more than 16 years) of NT and conventional tillage (CT). Samples were taken from different regions of Argentina corresponding to: Paraná soil (PAR), a silty clay loam soil (< 37% clay), Manfredi (MAN) and Pergamino (PER), both silty loam soils (< 26% clay). We found that the adsorption was very high in all the soils, and it was particularly influenced by the soil clay content and CEC and negatively related to pH and phosphorus. In general, the adsorption coefficient (Kf) was higher in the CT samples. We also studied the vertical transport of glyphosate in undisturbed columns (15 cm long) and compared the effect of NT and CT. Less than 0.24% of the applied pesticide leached in all soils. No significant difference was found between the total amount of leached glyphosate between soils or tillage practice. The highest glyphosate concentration (67.53% of the initially applied doses) was found in the top 5 cm of the columns. The strong retention of glyphosate to the soil matrix, as confirmed by the high Kf values obtained in the isotherm studies, was the dominant factor influencing glyphosate mobility through the soil profile.

Entre lo público y lo privado: Empleadores y trabajadoras domésticas frente al Tribunal del Trabajo Doméstico de la ciudad de Buenos Aires; Between the public and the private worlds: Employers and domestic workers before the Council of Domestic Workin Buenos Aires Pérez, Inés; Canevaro, Santiago El servicio doméstico ocupa un lugar ambiguo entre los mundos público y privado. Desarrollado en el interior de los hogares de los empleadores, da lugar a relaciones en las que lo laboral y lo afectivo están imbricados. Los juicios laborales entre empleadores y trabajadoras domésticas constituyen un escenario privilegiado para observar el solapamiento de estas dimensiones. Si las demandas de las trabajadoras frente a las instituciones de justicia sitúan esta relación en el mundo público, las respuestas de los empleadores muchas veces buscan resituarlas en el orden privado. Por otra parte, en algunos escenarios, las demandas de las trabajadoras son también expresadas en un lenguaje que remite a lo privado. En este artículo analizamos las lógicas de la confl ictividad judicial establecidas en las estrategias de empleadores y trabajadoras frente al Tribunal del Trabajo Doméstico (TTD), un organismo creado en 1956 para atender los confl ictos individuales que derivan de las relaciones de trabajo de este sector en la ciudad de Buenos Aires. Tomamos dos horizontes temporales caracterizados por cambios en la regulación del trabajo, en general, y del servicio doméstico, en particular: el de los primeros años de funcionamiento del TTD y el cambio de siglo.; Domestic service occupies an ambiguous place between the public and private worlds. Performed inside the employers’ homes, it gives place to relationships in which labor and affection are intertwined. The labor lawsuits between employers and domestic workers are a privileged stage to watch the overlap of these dimensions. While the demands of the workers before the institutions of justice put these relationships in the public world, the responses of employers often seek to resituate them in the private domain. Moreover, in some scenarios, the demands of the workers were also expressed in a language that refers to the private sphere. This article analyzes the logics of judicial confl icts in the strategies of employers and workers before the Council of Domestic Work (TTD), an institution created in 1956 to address individual disputes arising from employment relations in this sector in the city of Buenos Aires. We take two time horizons characterized by changes in labor regulation in general terms and, particularly, in domestic service: the early years of the TTD and the turn of the twentieth century.

Consumo de alcohol y su relación con la autopercepción adolescente; Alcohol consumption and its relationship with the adolescent self-perception Calero, Alejandra Daniela; Schmidt, Vanina Ines; Bugallo, Lucía Resumen. a) Fundamentación. El consumo de alcohol en la adolescencia representa un problema de salud pública prioritario dada su prevalencia en este grupo etario. Asimismo, las autopercepciones han mostrado tener una gran importancia para el desarrollo adolescente. b) Objetivos. Estudiar la relación entre la cantidad y frecuencia de consumo de alcohol y los dominios del autoconcepto y la autoestima durante la adolescencia. c) Metodología. Participaron 397 adolescentes escolarizados de la Ciudad Autónoma de Buenos Aires, quienes respondieron el Cuestionario Consumo –Frecuencia- CEEA (consumo episódico excesivo de alcohol) y el Perfil de Autopercepción. d) Resultados. Los adolescentes que indicaron un mejor autoconcepto en atractivo amoroso consumen más cantidad de alcohol y con más frecuencia. Se encontraron diferencias en los resultados en función del grado de escolaridad de los adolescentes y también en función del sexo. Asimismo, se hallaron diferencias en distintos dominios del autoconcepto entre abstinentes y consumidores moderados con CEEA. e) Conclusión. Las conclusiones derivadas del presente estudio podrían interpretarse considerando el estereotipo adolescente imperante, y la naturalización y tolerancia social respecto del consumo, todos aspectos del contexto social en el que los adolescentes se desarrollan y construyen el concepto de sí.

REGISTRO DE NIDIFICACIÓN DEL MACÁ GRIS (Tachybaptus dominicus) EN SANTA FE, ARGENTINA Lorenzón, Rodrigo Ezequiel; Antoniazzi, C.E.; Beltzer, A. El Macá Gris (Tachybaptus dominicus) se distribuye desde el sur de Estados Unidos y las Antillas Mayores hasta el centro-norte de Argentina y sur de Uruguay. En Argentina es considerado escaso o raro por la mayoría de los autores . En Argentina, el área reproductiva del Macá Gris es poco conocida debido a la escasa evidencia documentada en los trabajos que mencionan su presencia. La especie nidificaría en las provincias del norte: Jujuy, Salta, Tucumán, Formosa y Chaco, la Mesopotamia: Corrientes, Entre Ríos y Misiones, y recientemente fue hallado nidificando en provincia de Buenos Aires. En Santa Fe cuenta con escasas observaciones y su estatus es desconocido. En esta nota presentamos algunas observaciones de una pareja de Macá Gris que nidificó en la localidad de Monte Vera, provincia de Santa Fe.

Communication: Isotopic effects on tunneling motions in the water trimer Videla, Pablo Ernesto; Rossky, Peter J.; Laria, Daniel Hector We present results of ring polymer molecular dynamics simulations that shed light on the effects of nuclear quantum fluctuations on tunneling motions in cyclic [H2O]3 and [D2O]3, at the representative temperature of T = 75 K. In particular, we focus attention on free energies associated with two key isomerization processes: The first one corresponds to flipping transitions of dangling OH bonds, between up and down positions with respect to the O-O-O plane of the cluster; the second involves the interchange between connecting and dangling hydrogen bond character of the H-atoms in a tagged water molecule. Zero point energy and tunneling effects lead to sensible reductions of the free energy barriers. Due to the lighter nature of the H nuclei, these modifications are more marked in [H2O]3 than in [D2O]3. Estimates of the characteristic time scales describing the flipping transitions are consistent with those predicted based on standard transition-state-approximation arguments.

Home at last: The enigmatic genera Eriachaenium and Adenocaulon (Compositae, Mutisioideae, Mutisieae, Adenocaulinae) Funk, Vicki A.; Pasini, Eduardo; Bonifacino, J. Mauricio; Katinas, Liliana The genera Eriachaenium and Adenocaulon (Compositae) have distinct but complex histories and both have been placed in a number of tribes across the family. For the first time the two genera are included in a molecular study and the results show that they are best placed in the tribe Mutisieae s.s. and are the only genera in the re-instated subtribe Adenocaulinae. When described, this subtribe contained only Adenocaulon and was found in the Inuleae. The study also confirms one of the conclusions of a recent morphological study that Eriachaenium and Adenocaulon are sister taxa. Past difficulties in tribal assignment are attributed to the distinct and unusual morphology of each genus. Both genera and the subtribe are described and a key to separate the genera is provided.

Microglia and astrocyte activation in the frontal cortex of rats with experimental autoimmune encephalomyelitis Chanaday Ricagni, Natalí Luján; Roth, German Alfredo Experimental autoimmune encephalomyelitis (EAE) is a widely used animal model for the human disease multiple sclerosis (MS), a demyelinating and neurodegenerative pathology of the central nervous system. Both diseases share physiopathological and clinical characteristics, mainly associated with a neuroinflammatory process that leads to a set of motor, sensory, and cognitive symptoms. In MS, gray matter atrophy is related to the emergence of cognitive deficits and contributes to clinical progression. In particular, injury and dysfunction in certain areas of the frontal cortex (FrCx) have been related to the development of cognitive impairments with high incidence, like central fatigue and executive dysfunction. In the present work we show the presence of region-specific microglia and astrocyte activation in the FrCx, during the first hours of acute EAE onset. It is accompanied by the production of the pro-inflammatory cytokines IL-6 and TNF-α, in the absence of detectable leukocyte infiltration. These findings expand previous studies showing presynaptic neural dysfunction occurring at the FrCx and might contribute to the understanding of the mechanisms involved in the genesis and prevalence of common MS symptoms.

Synergism in the desorption of polycyclic aromatic hydrocarbons from soil models by mixed surfactant solutions Sales, Pablo Sebastián; Fernández, Mariana Adela This study investigates the effect of a mixed surfactant system on the desorption of polycyclic aromatic hydrocarbons (PAHs) from soil model systems. The interaction of a non-ionic surfactant, Tween 80, and an anionic one, sodium laurate, forming mixed micelles, produces several beneficial effects, including reduction of adsorption onto solid of the non-ionic surfactant, decrease in the precipitation of the fatty acid salt, and synergism to solubilize PAHs from solids compared with individual surfactants.

Dark-soliton collisions in a toroidal Bose-Einstein condensate Jezek, Dora Marta; Capuzzi, Pablo; Cataldo, Horacio Maximo We study the dynamics of two gray solitons in a Bose-Einstein condensate confined by a toroidal trap with a tight confinement in the radial direction. Gross-Pitaevskii simulations show that solitons can be long-living objects passing through many collisional processes. We have observed quite different behaviors depending on the soliton velocity. Very slow solitons, obtained by perturbing the stationary solitonic profile, move with a constant angular velocity until they collide elastically and move in the opposite direction without showing any sign of lowering their energy. In this case the density notches are always well separated and the fronts are sharp and straight. Faster solitons present vortices around the notches, which play a central role during the collisions. We have found that in these processes the solitons lose energy, as the outgoing velocity turns out to be larger than the incoming one. To study the dynamics, we model the gray soliton state with a free parameter that is related to the soliton velocity. We further analyze the energy, soliton velocity, and turning points in terms of such a free parameter, finding that the main features are in accordance with the infinite one-dimensional system.

Independent Evolution of Suction Feeding in Neobatrachia: Feeding Mechanisms in Two Species of Telmatobius (Anura:Telmatobiidae) Barrionuevo, Jose Sebastian The most common feeding mechanism among aquatic vertebrates as fishes, turtles, and salamanders is inertial suction. However, among the more than 6,400 species of anurans, suction feeding occurs only in pipids. Pipidae is a small basal lineage relative to Neobatrachia, an enormous clade that contains about 96% of extant anurans. The Andean neobatrachian frogs of the genus Telmatobius include strictly aquatic and semiaquatic species. Diet analyses indicate that some species of Telmatobius feed on strictly aquatic prey, but until now their feeding mechanisms have been unknown. Herein, the feeding mechanisms in two species of Telmatobius, that represent the two predominant modes of life in the genus, are explored. The semiaquatic T. oxycephalus and the fully aquatic T. rubigo are studied using high-speed cinematography and standard anatomical techniques to provide a qualitative approach to feeding behavior and a detailed morphological description of the mouth, tongue, hyoid and related muscles. T. oxycephalus uses similar mechanisms of aquatic prey capture as do the vast majority of anurans that are capable of forage in water, whereas the fully aquatic T. rubigo is an inertial suction feeder. This is the first report of an objective record of this unique feeding behavior in a Neobatrachian. Several morphological characters seem to be related with this function and are convergent with those of pipids.

Acquired TERT promoter mutations activate TERT expression in mantle cell lymphoma Panero, Julieta; Alves Paiva, Raquel; Roisman, Alejandro; Santana Lemos, Barbara; Falcao, Roberto P.; Oliveira, Gustavo; Martins, Diego; Stanganelli, Carmen Graciela; Slavutsky, Irma Rosa; Calado, Rodrigo Mantle cell lymphoma (MCL) is an aggressive lymphoid neoplasm with poor prognosis. Acquired telomerasereverse transcriptase gene promoter (TERTp) mutations are among the most frequent somatic non-codingmutations in cancers. In this study, the prevalence of TERTp mutations in 24 MCL and 21 other lymphoidneoplasias (oLN) was investigated. Eight MCL samples (33%) carried TERTp mutations, two homozygous andsix heterozygous (seven C228T and one C250T), which directly correlated with higher TERT transcription,mitochondrial DNA copy number, and IGHV mutational status in MCL neoplastic cells. TERTp mutations werenot found in oLN. TERTp mutations correlated with more lymphoma proliferation and tumor burden, assuggested by the higher number of lymphoma cells circulating in peripheral blood, and tended to associatewith longer MCL telomeres, especially in homozygous mutants, although not statistically significant.Telomere-biology genes were overexpressed in MCL cells in comparison to healthy lymphocytes, but werenot influenced by mutation status. The findings described for the first time that acquired TERTp mutationsare common in MCL but not in other lymphoid neoplasms. It was also demonstrated that TERTp mutationsassociated with higher TERT mRNA expression in MCL cells in vivo and higher tumor burden, suggestingthese mutations as a driver event in MCL development and progression.

Soluble RANKL production by leukemic cells in a case of chronic lymphocytic leukemia with bone destruction Borge, Mercedes; Delpino, María Victoria; Podaza, Enrique Arturo; Stanganelli, Carmen Graciela; Palau Nagore, Maria Virginia; Roisman, Alejandro; Slavutsky, Irma Rosa; Palacios, Maria F.; Ledesma, Ignacio; Arra, Antonio; Diaz, Alicia; Giordano, Mirta Nilda; Gamberale, Romina; Bezares, Raimundo F. Receptor Activator for Nuclear Factor j B Ligand(RANKL) is a member of the TNF-a superfamily normallyproduced by osteoblasts and stromal cells, whichactivates its receptor RANK present on osteoclasts andosteoclast precursors, thus favoring their differentiationand activity. An aberrant expression of RANKL was previouslyreported in a proportion of B cell malignanciessuch as Chronic lymphocytic leukemia (CLL), multiplemyeloma (MM) and follicular lymphoma

Physiological and genetic differences amongst Rhodococcus species for using glycerol as a source for growth and triacylglycerol production Herrero, Ornella Marisa; Moncalián, Gabriel; Alvarez, Hector Manuel We analysed the ability of five different rhodococcal species to grow and produce triacylglycerols (TAGs) from glycerol, the main byproduct of biodiesel production. Rhodococcus fascians and Rhodococcus erythropolis grew fast on glycerol, whereas Rhodococcus opacus and Rhodococcus jostii exhibited a prolonged lag phase of several days before growing. Rhodococcus equi only exhibited poor growth on glycerol. R. erythropolis DSMZ 43060 and R. fascians F7 produced 3.9–4.3 g cell biomass l− 1 and 28.4–44.6 % cellular dry weight (CDW) of TAGs after 6 days of incubation; whereas R. opacus PD630 and R. jostii RHA1 produced 2.5–3.8 g cell biomass l− 1 and 28.3–38.4 % CDW of TAGs after 17 days of growth on glycerol. Genomic analyses revealed two different sets of genes for glycerol uptake and degradation (here named clusters 1 and 2) amongst rhodococci. Those species that possessed cluster 1 (glpFK1D1) (R. fascians and R. erythropolis) exhibited fast growth and lipid accumulation, whereas those that possessed cluster 2 (glpK2D2) (R. opacus, R. jostii and R. equi) exhibited delayed growth and lipid accumulation during cultivation on glycerol. Three glycerol-negative strains were complemented for their ability to grow and produce TAGs by heterologous expression of glpK2 from R. opacus PD630. In addition, we significantly reduced the extension of the lag phase and improved glycerol assimilation and oil production of R. opacus PD630 when expressing glpK1D1 from R. fascians. The results demonstrated that rhodococci are a flexible and amenable biological system for further biotechnological applications based on the reutilization of glycerol.

Human Microbiota of the Argentine Population- A pilot study Carbonetto, María Belén; Fabbro Frías, Mónica Carolina; Sciara, Mariela Ines; Serevalle, Analia; Mejico, Guadalupe; Revale, Santiago; Romero, Soledad; Brun, Bianca; Fay, Marcelo; Fay, Fabian; Vazquez, Martin Pablo The human microbiota is the collection of microorganisms living in or on the human body. An imbalance or dysbiosis in these microbial communities can be associated with a wide variety of human diseases (Petersen and Round, 2014; Pham and Lawley, 2014; Zaura et al., 2014). Moreover, when the microbiota of the same body sites is compared between different healthy individuals, specific microbial community features are apparent (Li et al., 2012; Yatsunenko et al., 2012; Oh et al., 2014; Relman, 2015). In addition, specific selective pressures are found at distinct body sites leading to different patterns in microbial community structure and composition (Costello et al., 2009; Consortium, 2012b; Zhou et al., 2013). Because of these natural variations, a comprehensive characterization of the healthy microbiota is critical for predicting alterations related to diseases. This characterization should be based on a broad healthy population over time, geography, and culture (Yatsunenko et al., 2012; Shetty et al., 2013; Leung et al., 2015; Ross et al., 2015). The study of healthy individuals representing different ages, cultural traditions, and ethnic origins will enable to understand how the associated microbiota varies between populations and respond to different lifestyles. It is important to address these natural variations in order to later detect variations related to disease.

Taxonomy of the Phyllotis osilae species group in Argentina; the status of the “Rata de los nogales” (Phyllotis nogalaris Thomas, 1921; Rodentia: Cricetidae) Jayat, Jorge Pablo; Ortiz, Pablo Edmundo; Gonzalez, Francisco Rodrigo; D'elía, Guillermo The taxonomic status of populations of the genus Phyllotis from northwestern Argentina (NWA) has undergone recent changes, with the addition of two species (P. alisosiensis and P. anitae) to the traditionally recognized forms (P. caprinus, P. xanthopygus, and P. osilae). Three of these species (P. anitae, P. osilae, and P. alisosiensis) were included within the Phyllotis osilae species group. Most authors recognized three subspecies of P. osilae for NWA: P. osilae osilae, P. o. nogalaris, and P. o. tucumanus. Morphological, morphometric, and molecular studies based on recently collected specimens suggest that current classification does not reflect the diversity of this group in NWA, revealing the need of some taxonomic reallocations and new distributional delimitations. Here we propose that P. nogalaris must be recognized as a valid species and the restriction of P. osilae to southern Peru and central Bolivia. Following our results, we expect an outstanding improvement in the taxonomic knowledge of the Phyllotis osilae species group in the coming years.

Action of fosetyl‐al and metalaxyl against Phytophthora austrocedri Silva, Patricia Valeria; Vélez, María Laura; Hernández Otaño, D.; Nuñez, C.; Greslebin, Alina Gabriela Fosetyl‐Al and metalaxyl, the most commonly used systemic fungicides against Phytophthora, were evaluated for their efficacy to control Phytophthora austrocedri, the pathogen that causes a serious disease at the Austrocedrus chilensis forests in Patagonia. The effect of the chemicals on pathogen development in vitro and in planta was analysed. Both chemicals were shown to protect plants from the pathogen. In vitro assays showed that asexual reproduction was sensitive to both chemicals. However, mycelial growth and sexual reproduction, which were clearly sensitive to metalaxyl, were sensitive only to high concentrations of fosetyl‐Al. Fosetyl‐Al and metalaxyl had almost the same efficacy when applied preventively by soil drench to seedlings. This difference between in vitro and in planta results can be attributed to the dual action of fosetyl‐Al, not only inhibiting the pathogen but also stimulating host defence. In adult trees, preventive and curative treatments were tested, but only the fosetyl‐Al preventive treatment was effective in the assayed conditions. Interestingly, seedlings pretreated with both fungicides were less susceptible to the effectors secreted by the pathogen. Our results indicate that fosetyl‐Al and metalaxyl provide some resistance to the plant besides the fungistatic direct action on the pathogen. Further studies to elucidate a possible resistance‐inducing activity of these chemicals and the mechanisms involved are underway.

Melatonin-Induced Oncostasis, Mechanisms and Clinical Relevance Cardinali, Daniel Pedro; Escames, Germaine; Acuña Castroviejo, Darío; Ortiz, Francisco; Fernández Gil, Beatriz; Guerra Librero, Ana; García López, Sergio; Shen, Ying; Florido, Javier Melatonin is a natural substance ubiquitously distributed and present in almost all living species, from unicellular organisms to humans. Melatonin is synthesized not only in the pineal gland but also in most tissues in the body where it may have a cytoprotective function via paracrine or autocrine effects. Melatonin is effective in suppressing neoplastic growth in a variety of tumors. The mechanisms involved include antiproliferative effects via modulation of cell cycle, ability to induce apoptosis in cancer cells, anti-angiogenic and antimetastatic effects, anti-estrogenic activity, the capacity to decrease telomerase activity, immune modulation, and direct and indirect antioxidant effects. Besides these oncostatic properties, melatonin deserves to be considered in the treatment of cancer for two other reasons. First, because its hypnotic-chronobiotic properties, melatonin use that can allow the clinician to effectively address sleep disturbances, a major co-morbidity in cancer. Second, because melatonin’s anxiolytic and antidepressant effects, it has a possible application in two other major co-morbidities seen in cancer patients, i.e. depression and anxiety. This report summarizes the possible mechanisms involved in melatonin oncostasis and reviews what is known about the clinical application of melatonin as an adjuvant therapy in cancer patients.

Thalidomide analogues: Tumor necrosis factor-alpha inhibitors and their evaluation as anti-inflammatory agents Casal, Juan José; Bollini, Mariela; Lombardo, Maria Elisa; Bruno, Ana María A series of related thalidomide derivatives (2-9) were synthesized by microwave irradiation and evaluated for anti-inflammatory activity. Such activity was assessed in vivo and ex vivo. Compounds 2, 8 and 9 showed the highest levels of inhibition of TNF-α production. On rat paw edema and hyperalgesia assays, compound 9, (1,4-phthalazinedione) demonstrated the highest in vivo anti-inflammatory activity. Thus, compound 9 can be considered as a promising compound to be subjected to further modification to obtain new agents for the treatment of inflammatory diseases.

The AIMSS Project, III : the stellar populations of compact stellar systems Janz, Joachin; Norris, Mark A.; Forbes, Duncan A.; Huxor, Avon; Romanowsky, Aaron; Frank, Matthias; Escudero, Carlos Gabriel; Faifer, Favio Raúl; Forte, Juan Carlos; Kannappan, Sheila J.; Maraston, Claudia; Brodie, Jean; Strader, Jay; Thompson, Bradley In recent years, a growing zoo of compact stellar systems (CSSs) have been found whose physical properties (mass, size, velocity dispersion) place them between classical globular clusters (GCs) and true galaxies, leading to debates about their nature. Here we present results using a so far underutilized discriminant, their stellar population properties. Based on new spectroscopy from 8-10m telescopes, we derive ages, metallicities, and [α/Fe] of 29 CSSs. These range from GCs with sizes of merely a few parsec to compact ellipticals (cEs) larger than M32. Together with a literature compilation, this provides a panoramic view of the stellar population characteristics of early-type systems. We find that the CSSs are predominantly more metal rich than typical galaxies at the same stellar mass. At high mass, the cEs depart from the mass-metallicity relation of massive early-type galaxies, which forms a continuous sequence with dwarf galaxies. At lower mass, the metallicity distribution of ultracompact dwarfs (UCDs) changes at a few times 10^7 M⊙, which roughly coincides with the mass where luminosity function arguments previously suggested the GC population ends. The highest metallicities in CSSs are paralleled only by those of dwarf galaxy nuclei and the central parts of massive early types. These findings can be interpreted as CSSs previously being more massive and undergoing tidal interactions to obtain their current mass and compact size. Such an interpretation is supported by CSSs with direct evidence for tidal stripping, and by an examination of the CSS internal escape velocities.

Hydroxylation and translational adaptation to stress: some answers lie beyond the STOP codon Katz, Maximiliano Javier; Gándara, Lautaro; de Lella Ezcurra, Ana Laura; Wappner, Pablo Regulation of protein synthesis contributes to maintenance of homeostasis and adaptation to environmental changes. mRNA translation is controlled at various levels including initiation, elongation and termination, through post-transcriptional/translational modifications of components of the protein synthesis machinery. Recently, protein and RNA hydroxylation have emerged as important enzymatic modifications of tRNAs, elongation and termination factors, as well as ribosomal proteins. These modifications enable a correct STOP codon recognition, ensuring translational fidelity. Recent studies are starting to show that STOP codon read-through is related to the ability of the cell to cope with different types of stress, such as oxidative and chemical insults, while correlations between defects in hydroxylation of protein synthesis components and STOP codon read-through are beginning to emerge. In this review we will discuss our current knowledge of protein synthesis regulation through hydroxylation of components of the translation machinery, with special focus on STOP codon recognition. We speculate on the possibility that programmed STOP codon read-through, modulated by hydroxylation of components of the protein synthesis machinery, is part of a concerted cellular response to stress.