Magnetic light and forbidden photochemistry: the case of singlet oxygen

[EN] Most optical processes occurring in nature are based on the well-known selection rules for opticaltransitions between electronic levels of atoms, molecules, and solids. Since in most situations themagnetic component of light has a negligible contribution, the dipolar electric approximation isgenerally assumed. However, this traditional understanding is challenged by nanostructured materials,which interact strongly with light and produce very large enhancements of the magnetic field in theirsurroundings. Here we report on the magnetic response of different metallic nanostructures and theirinfluence on the spectroscopy of molecular oxygen, a paradigmatic example of dipole-forbidden optical transitions in photochemistryA. M. acknowledge support from U. S. National Science Foundation (Grant ECCS-1710697). The authors acknowledge the financial support from the following projects: CTQ2014-61671-EXP, MAT2015-69669-P, and PrometeoII/2017/026. 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MEJORAMIENTO GENÉTICO EN VID DE MESA:EFECTO DE LOS PROGENITORES EN EL AMARRE DE BAYAS

Los centros de mejoramiento genético de la vid en el mundo están localizados en zonas templadas en latitudes mayores de 30 grados en ambos hemisferios, donde las condiciones climáticas son benignas para realizar los cruzamientos (Tabla I). Se conoce que las temperatura entre 15 y 25 o C son las más favorables para tener éxito en las hibridaciones en los frutales (Layne, 1988; Stanley y Linskens, 1974). Además, los procesos de selección normalmente se realizan bajo esas condiciones lo que lleva a que las variedades que se generen estén adaptadas a condiciones de clima templado. Con el fin de generar variedades adaptadas a las condiciones desérticas, se inició un programa de mejoramiento genético en vid, donde una de las primeras fases consistió en evaluar el amarre de bayas en cruzas entre diferentes variedades para evaluar el potencial para obtener progenie. Los cruzamientos se realizaron en el Campo Experimental de la Costa de Hermosillo en las primeras tres semanas de abril del 2009, utilizando las variedades listadas en la Tabla II. Dos días antes de la antesis se llevó a cabo la emasculación y polinización utilizando polen fresco colectado en campos de agricultores cooperantes (Einset y Pratt, 1975)

Adaptación de inteligencia artificial por el modelo de regresión múltiple estocástica para determinar la calidad de la fibra de alpaca (Lama pacos)

The application of artificial intelligence based on the multiple linear regression model with stochastic descending gradient is described in order to determine the quality of the white Huacaya alpaca fibre. In total, 1200 fibres corresponding to six alpaca samples were analysed. The fibres were characterized by optical microscopy and with the optical fibre diameter analyser (OFDA 100) equipment. Fibre diameter, medulla diameter, percentage of medullation by volume, comfort factor, and objectionable fibres were considered as independent variables, and the “Soft” factor was considered as a response variable. This last variable resulting from the difference in the comfort factor and objectionable fibres served to give a logical order to the data matrix and obtain an accurate prediction model. The average values were 26.80 ± 6.95 for the fibre diameter, 14.10 ± 5.92 for the medulla diameter, 24.75 ± 13.20 µm for the percentage of medullation by volume and 71.56 ± 13.04% for the comfort factor. The machine learning multiple linear regression modelling fitted a small sample size with high precision, showing minimal errors, and optimized with the stochastic gradient descent algorithm predicted a Soft factor very close to the observed Soft factor. It is concluded that the multiple linear regression technique with the stochastic approach satisfies the prediction of the new factor called "soft" and that it represents the appropriate modelling for the prediction of fibre quality in the textile industry.Se describe la aplicación de inteligencia artificial basada en el modelo de regresión lineal múltiple con gradiente descendiente estocástica con la finalidad de determinar la calidad de la fibra de alpaca Huacaya de color blanco. Se analizaron 1200 fibras correspondientes a seis muestras de alpaca. Las fibras se caracterizaron mediante microscopía óptica y con el equipo analizador óptico de diámetro de fibra (OFDA 100). Se consideraron como variables independientes al diámetro de fibra, diámetro de médula, porcentaje de medulación por volumen, factor de confort, fibras objetables y como variable de respuesta al factor “Soft”. Esta última variable resultante de la diferencia del factor de confort y fibras objetables sirvió para darle un ordenamiento lógico a la matriz de datos y obtener un modelo de predicción preciso. Los valores promedio fueron 26.80±6.95 para el diámetro de fibra, 14.10±5.92 en diámetro de medula, 24.75±13.20 μm para el porcentaje de medulación por volumen y 71.56± 13.04% para el factor de confort. El modelamiento de regresión lineal múltiple de machine learning se adaptó con gran precisión a un tamaño muestral pequeño, mostrando errores mínimos, y optimizado con el algoritmo de gradiente descendiente estocástico predijo un factor Soft muy cercano al factor Soft observado. Se concluye que la técnica de regresión lineal múltiple con el enfoque estocástico satisface la predicción del nuevo factor denominado “soft” y que representa el modelamiento adecuado para la predicción de calidad de fibras en la industria textil

Galectin-3 Deletion Reduces LPS and Acute Colitis-Induced Pro-Inflammatory Microglial Activation in the Ventral Mesencephalon

Parkinson’s disease is a highly prevalent neurological disorder for which there is currently no cure. Therefore, the knowledge of risk factors as well as the development of new putative molecular targets is mandatory. In this sense, peripheral inflammation, especially the originated in the colon, is emerging as a predisposing factor for suffering this disease. We have largely studied the pleiotropic roles of galectin-3 in driving microglia-associated immune responses. However, studies aimed at elucidating the role of galectin-3 in peripheral inflammation in terms of microglia polarization are lacking. To achieve this, we have evaluated the effect of galectin-3 deletion in two different models of acute peripheral inflammation: intraperitoneal injection of lipopolysaccharide or gut inflammation induced by oral administration of dextran sodium sulfate. We found that under peripheral inflammation the number of microglial cells and the expression levels of pro-inflammatory mediators take place specifically in the dopaminergic system, thus supporting causative links between Parkinson’s disease and peripheral inflammation. Absence of galectin-3 highly reduced neuroinflammation in both models, suggesting an important central regulatory role of galectin-3 in driving microglial activation provoked by the peripheral inflammation. Thus, modulation of galectin-3 function emerges as a promising strategy to minimize undesired microglia polarization states.This work was supported by grants from the Spanish Ministerio de Ciencia, Innovación y Universidades (RTI 2018-098830-B-I00), from the Consejería de Economía y Conocimiento of Junta de Andalucía (P18-RT-1372 and US-1264806). MJP, MDVC and PGM were supported by a grant from the Junta de Andalucía (CTS 5884) and AEC by an associated post-doctoral grant

Cranial and extracranial giant cell arteritis do not exhibit differences in the IL6 -174 G/C gene polymorphism

Since interleukin-6 (IL-6) is a pivotal proinflammatory cytokine implicated in the pathogenesis of giant cell arteritis (GCA), we aimed to determine the potential association of the functional IL6 -174 G/C polymorphism with GCA as well as if the single base change variation at the promoter region in the human IL-6 gene may account for differences in the clinical spectrum of GCA between cranial and extracranial large vessel vasculitis (LVV)-GCA

Cranial and extracranial large-vessel giant cell arteritis share a genetic pattern of interferon-gamma pathway

OBJECTIVES: Two main different clinical phenotypes of giant cell arteritis (GCA) have been described, the classic cranial pattern and the extracranial large-vessel (LV) pattern. Since interferon gamma (IFNG) has shown to be a pivotal cytokine in the pathophysiology of GCA, our aim was to evaluate for the first time the influence of IFNG and IFNG receptor 1 (IFNGR1) polymorphisms in the different clinical phenotypes of GCA. METHODS: Two IFNG polymorphisms (rs2069718 G/A and rs1861493 A/G) and one polymorphism in IFNGR1 (rs1327474 G/A) were genotyped in 191 patients with biopsy-proven cranial GCA, 109 with extracranial LV-GCA and 490 healthy controls. A comparative study was conducted between patients with cranial and extracranial LV-GCA. RESULTS: No significant differences in genotype, allele, and haplotype frequencies of IFNG polymorphisms were found between GCA patients with the classic cranial pattern and the extracranial LV-GCA pattern. Similar results were found for genotype and allele frequencies of IFNGR1 polymorphism. It was also the case when patients with extracranial LV-GCA were compared with healthy controls. CONCLUSIONS: Our results show that IFNG and IFNGR1 polymorphisms do not influence the clinical phenotype of expression of GCA. Classic cranial GCA and extracranial LV-GCA seem to share a genetic pattern of IFNG pathway

The presence of both HLA-DRB1[*]04:01 and HLA-B[*]15:01 increases the susceptibility to cranial and extracranial giant cell arteritis.

Objectives: To determine if patients with the predominant extracranial large-vessel-vasculitis (LVV) pattern of giant cell arteritis (GCA) have a distinctive HLA-B association, different from that reported in biopsy-proven cranial GCA patients. In a further step we assessed if the combination of HLA-B and HLA-DRB1 alleles confers an increased risk for GCA susceptibility, either for the cranial and extracranial LVV phenotypes. Methods: A total of 184 patients with biopsy-proven cranial GCA, 105 with LVV-GCA and 486 healthy controls were included in our study. We compared HLA-B phenotype frequencies between the three groups. Results: HLA-B*15 phenotype was significantly increased in patients with classic cranial GCA compared to controls (14.7% versus 5.8%, respectively; p<0.01; OR [95% CI] =2.81 [1.54-5.11]). It was mainly due to the HLA-B*15:01 allele (12.5% versus 4.0%, respectively; p<0.01; OR [95% CI] =3.51 [1.77-6.99]) and remained statistically significant after Bonferroni correction. Similar HLA-B*15 association was observed in patients with the LVV-GCA (11.4% versus 5.8%, p=0.04, OR [95% CI] =2.11 [1.04-4.30]). This association was also mainly due to the HLA-B*15:01 allele (10.5% versus 4.0%, respectively; p=0.0054; OR [95% CI] =2.88 [1.19-6.59]). Noteworthy, the presence of HLA-B*15:01 together with HLA-DRB1*04:01 led to an increased risk of developing both cranial and extracranial LVV-GCA. Conclusions: Susceptibility to GCA is strongly related to the HLA region, regardless of the clinical phenotype of expression of the disease.This work was partially supported by RETICS Programs, RD08/0075 (RIER), RD12/0009/0013 and RD16/0012 from ‘‘Instituto de Salud Carlos III’’ (ISCIII) (Spain). However, this research did not receive any specific grant from funding agencies in the commercial or not-for-profit sectors

Use of glucocorticoids megadoses in SARS-CoV-2 infection in a spanish registry: SEMI-COVID-19

Objective To describe the impact of different doses of corticosteroids on the evolution of patients with COVID-19 pneumonia, based on the potential benefit of the non-genomic mechanism of these drugs at higher doses. Methods Observational study using data collected from the SEMI-COVID-19 Registry. We evaluated the epidemiological, radiological and analytical scenario between patients treated with megadoses therapy of corticosteroids vs low-dose of corticosteroids and the development of complications. The primary endpoint was all-cause in-hospital mortality according to use of corticosteroids megadoses. Results Of a total of 14,921 patients, corticosteroids were used in 5,262 (35.3%). Of them, 2,216 (46%) specifically received megadoses. Age was a factor that differed between those who received megadoses therapy versus those who did not in a significant manner (69 years [IQR 59-79] vs 73 years [IQR 61-83]; p < .001). Radiological and analytical findings showed a higher use of megadoses therapy among patients with an interstitial infiltrate and elevated inflammatory markers associated with COVID-19. In the univariate study it appears that steroid use is associated with increased mortality (OR 2.07 95% CI 1.91-2.24 p < .001) and megadose use with increased survival (OR 0.84 95% CI 0.75-0.96, p 0.011), but when adjusting for possible confounding factors, it is observed that the use of megadoses is also associated with higher mortality (OR 1.54, 95% CI 1.32-1.80; p < .001). There is no difference between megadoses and low-dose (p.298). Although, there are differences in the use of megadoses versus low-dose in terms of complications, mainly infectious, with fewer pneumonias and sepsis in the megadoses group (OR 0.82 95% CI 0.71-0.95; p < .001 and OR 0.80 95% CI 0.65-0.97; p < .001) respectively. Conclusion There is no difference in mortality with megadoses versus low-dose, but there is a lower incidence of infectious complications with glucocorticoid megadoses