Role of retinal pigment epithelium-derived exosomes and autophagy in new blood vessel formation

Autophagy and exosome secretion play important roles in a variety of physiological and disease states, including the development of age‐related macular degeneration. Previous studies have demonstrated that these cellular mechanisms share common pathways of activation. Low oxidative damage in ARPE‐19 cells, alters both autophagy and exosome biogenesis. Moreover, oxidative stress modifies the protein and genetic cargo of exosomes, possibly affecting the fate of surrounding cells. In order to understand the connection between these two mechanisms and their impact on angiogenesis, stressed ARPE‐19 cells were treated with a siRNA‐targeting Atg7, a key protein for the formation of autophagosomes. Subsequently, we observed the formation of multivesicular bodies and the release of exosomes. Released exosomes contained VEGFR2 as part of their cargo. This receptor for VEGF—which is critical for the development of new blood vessels—was higher in exosome populations released from stressed ARPE‐19. While stressed exosomes enhanced tube formation, exosomes became ineffective after silencing VEGFR2 in ARPE‐19 cells and were, consequently, unable to influence angiogenesis. Moreover, vessel sprouting in the presence of stressed exosomes seems to follow a VEGF‐independent pathway. We propose that abnormal vessel growth correlates with VEGFR2‐expressing exosomes release from stressed ARPE‐19 cells, and is directly linked to autophagy

No radiographic sacroiliitis progression was observed in patients with early spondyloarthritis at 6 years: results of the Esperanza multicentric prospective cohort

Objective: To estimate the 6-year radiographic progression of sacroiliitis in patients with early spondyloarthritis (SpA). Patients and methods: Sacroiliac joint (SIJ) radiographs (baseline and 6 years) of 94 patients with recent-onset SpA from the Esperanza cohort were scored, blindly and in a random order, by nine readers. The modified New York criteria were used to define the presence of sacroiliitis. As the gold standard for radiographic (r) sacroiliitis, the categorical opinion of at least five readers was used. Progression was defined as the shift from non-radiographic (nr) to r-sacroiliitis. Results: In the 94 SIJ radiographs (baseline and 6 years), 78/94 (83%) pairs of radiographs had not changed from baseline to 6 years. Sacroiliitis was present in 20 patients at baseline (21.3%) and in 18 (19.2%) patients at 6 years; 11 patients had sacroiliitis at both the baseline and final visits; 9 patients changed from baseline r-sacroiliitis to nr-sacroiliitis at 6 years, and 7 changed from baseline nr-sacroiliitis to r-sacroiliitis at 6 years. The mean continuous change score (range: -8 to +8) was 2.80 at baseline and 2.55 at 6 years (mean net progression of -0.25). The reliability of the readers was fair (mean inter-reader kappa of 0.375 (0.146-0.652) and mean agreement of 73.7% (58.7-90%)). Conclusion: In the early SpA Esperanza cohort, progression from nr-axSpA to r-axSpA over 6 years was not observed, although the SIJ radiographs scoring has limitations to detect low levels of radiographic progression

Do native brown trout and non-native brook trout interact reproductively?

Reproductive interactions between native and non-native species of fish have received little attention compared to other types of interactions such as predation or competition for food and habitat. We studied the reproductive interactions between non-native brook trout (Salvelinus fontinalis) and native brown trout (Salmo trutta) in a Pyrenees Mountain stream (SW France). We found evidence of significant interspecific interactions owing to consistent spatial and temporal overlap in redd localizations and spawning periods. We observed mixed spawning groups composed of the two species, interspecific subordinate males, and presence of natural hybrids (tiger trout). These reproductive interactions could be detrimental to the reproduction success of both species. Our study shows that non-native species might have detrimental effects on native species via subtle hybridization behavior

Programa piloto de uso del portafolio como herramienta docente en el Grado de Biología

Memoria final del proyecto de Innovación educativa "Programa piloto de uso del portafolio como herramienta docente en el Grado de Biología

Environmental design solutions for existing concrete flat roofs in low-cost housing to improve passive cooling in western Mexico

The development of real estate in Mexico has largely ruled out the comfort of users that focused on economic matters and made it difficult to make substantial progress in adopting measures to improve indoor environmental quality. Current research projects in Mexico found that roof construction in low-cost housing struggles to meet the requirements of the indoor climate. Passive cooling strategies are techniques to control heat gain and heat dissipation in buildings to maximise the comfort and health of building users while minimising energy use. Passive cooling systems recognize climate conditions and utilise renewable sources of energy such as the sun and wind to provide cooling and ventilation. Therefore, this study aims to develop a green and sustainable solution for existing concrete flat roofs with no major interventions and investments to save energy. The design of a passive device was tested to assess its effectiveness to protect flat roofs from shortwave radiation and to allow for heat dissipation in Mexican buildings. The study used a quantitative approach based on experiments and simulation tests to evaluate design efficiency. The results showed that a perforated device with an opening percentage of 88% and a cavity of 0.05m between the roof and the device provided effective protection. Also, the device with blinds of 45° showed lower operative temperatures within a range of mean values between 0.8°C and 0.9°C compared to a roof with a full shade cover in the hot and humid season. However, the perforated device with blinds of 90° in black colour delivered the best performance compared to other models and recorded a mean value of 1.13°C in the hot sub-humid season. The results revealed the efficiency of the proposed device that can be observed within different geometric configurations, surface properties as well as the use of the nocturnal radiative cooling potential in blocking solar radiation in Mexican buildings

Theoretical insights into the regioselectivity of a Pictet-Spengler reaction: transition state structures leading to salsolinol and isosalsolinol

The mechanism of the cyclization step of the Pictet-Spengler reaction between acetaldehyde and dopamine to give salsolinol and isosalsolinol was studied computationally, using density functional theory. The preferential formation in acidic media of salsolinol, the product of para-cyclization, and the requirement of a neutral pH for the formation of the ortho-cyclized isosalsolinol are explained in terms of 2 different mechanistic routes with an iminium ion or a phenolate-iminium zwitterion as starting reactants.FONDECYT 1112127

Editing melon eIF4E associates with virus resistance and male sterility

The cap-binding protein eIF4E, through its interaction with eIF4G, constitutes the core of the eIF4F complex, which plays a key role in the circularization of mRNAs and their subsequent cap-dependent translation. In addition to its fundamental role in mRNA translation initiation, other functions have been described or suggested for eIF4E, including acting as a proviral factor and participating in sexual development. We used CRISPR/Cas9 genome editing to generate melon eif4e knockout mutant lines. Editing worked efficiently in melon, as we obtained transformed plants with a single-nucleotide deletion in homozygosis in the first eIF4E exon already in a T0 generation. Edited and non-transgenic plants of a segregating F2 generation were inoculated with Moroccan watermelon mosaic virus (MWMV); homozygous mutant plants showed virus resistance, while heterozygous and non-mutant plants were infected, in agreement with our previous results with plants silenced in eIF4E. Interestingly, all homozygous edited plants of the T0 and F2 generations showed a male sterility phenotype, while crossing with wild-type plants restored fertility, displaying a perfect correlation between the segregation of the male sterility phenotype and the segregation of the eif4e mutation. Morphological comparative analysis of melon male flowers along consecutive developmental stages showed postmeiotic abnormal development for both microsporocytes and tapetum, with clear differences in the timing of tapetum degradation in the mutant versus wild-type. An RNA-Seq analysis identified critical genes in pollen development that were down-regulated in flowers of eif4e/eif4e plants, and suggested that eIF4E-specific mRNA translation initiation is a limiting factor for male gametes formation in melonThis work was supported by grants AGL2015-65838 and PLEC2021-007715 from Ministerio de Ciencia e Innovacion (Spain) and 2I16SA000057 of the RIS3Mur program from Consejería de empleo, universidades y empresa (Region de Murcia, Spain) and 20800/PI/18 from Fundacion Seneca, Murcia. GSP was supported by grant BES-2016-077826 (Ministerio de Ciencia e Innovacion; Spain

Monitoring the Extent of Contamination from Acid Mine Drainage in the Iberian Pyrite Belt (SW Spain) Using Hyperspectral Imagery

Monitoring mine waste from sulfide deposits by hyperspectral remote sensing can be used to predict surface water quality by quantitatively estimating acid drainage and metal contamination on a yearly basis. In addition, analysis of the mineralogy of surface crusts rich in soluble salts can provide a record of annual humidity and temperature. In fact, temporal monitoring of salt efflorescence from mine wastes at a mine site in the Iberian Pyrite Belt (Huelva, Spain) has been achieved using hyperspectral airborne Hymap data. Furthermore, climate variability estimates are possible based on oxidation stages derived from well-known sequences of minerals, by tracing sulfide oxidation intensity using archive spectral libraries. Thus, airborne and spaceborne hyperspectral remote sensing data can be used to provide a short-term record of climate change, and represent a useful set of tools for assessing environmental geoindicators in semi-arid areas. Spectral and geomorphological indicators can be monitored on a regular basis through image processing, supported by field and laboratory spectral data. In fact, hyperspectral image analysis is one of the methods selected by the Joint Research Centre of the European Community (Ispra, Italy) to study abandoned mine sites, in order to assess the enforcement of the European Mine Waste Directive (2006/21/EC of the European Parliament and of the Council 15 March 2006) on the management of waste from extractive industries (Official Journal of the European Union, 11 April 2006). The pyrite belt in Andalucia has been selected as one of the core mission test sites for the PECOMINES II program (Cracow, November 2005), using imaging spectroscopy; and this technique is expected to be implemented as a monitoring tool by the Environmental Net of Andalucía (REDIAM, Junta de Andalucía, Spain)