Interplay of space radiation and microgravity in DNA damage and DNA damage response

In space, multiple unique environmental factors, particularly microgravity and space radiation, pose constant threat to the DNA integrity of living organisms. Specifically, space radiation can cause damage to DNA directly, through the interaction of charged particles with the DNA molecules themselves, or indirectly through the production of free radicals. Although organisms have evolved strategies on Earth to confront such damage, space environmental conditions, especially microgravity, can impact DNA repair resulting in accumulation of severe DNA lesions. Ultimately these lesions, namely double strand breaks, chromosome aberrations, micronucleus formation, or mutations, can increase the risk for adverse health effects, such as cancer. How spaceflight factors affect DNA damage and the DNA damage response has been investigated since the early days of the human space program. Over the years, these experiments have been conducted either in space or using ground-based analogs. This review summarizes the evidence for DNA damage induction by space radiation and/or microgravity as well as spaceflight-related impacts on the DNA damage response. The review also discusses the conflicting results from studies aimed at addressing the question of potential synergies between microgravity and radiation with regard to DNA damage and cellular repair processes. We conclude that further experiments need to be performed in the true space environment in order to address this critical question.publishe

La sociopoética de la identidad como nuevo método de educación literaria a través de los cuentos populares: los hermanos Grimm

Este trabajo supone una reflexión de los aprendizajes realizados durante el Máster de Profesorado de Educación Secundaria y Bachillerato en la especialidad de Lengua Castellana y Literatura, así como una breve síntesis explicativa del proyecto de innovación que realicé durante el Prácticum III. Dicho proyecto se centra en tres cuentos de los hermanos Grimm para trabajar la identidad literaria y la autobiografía con los adolescentes

Protein profiling and classification of commercial quinoa grains by MALDI-TOF-MS and chemometrics

Quinoa is an Andean grain that is attracting attention worldwide as a high-quality protein-rich food. Nowadays, quinoa foodstuffs are susceptible to adulteration with cheaper cereals. Therefore, there is a need to develop novel methodologies for protein characterization of quinoa. Here, we first developed a matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) method to obtain characteristic mass spectra of protein extracts from 4 different commercial quinoa grains, which group different varieties marketed as black, red, white (from Peru) and royal (white from Bolivia). Then, data preprocessing and peak detection with MALDIquant allowed detecting 47 proteins (being 30 tentatively identified), the intensities of which were considered as fingerprints for multivariate data analysis. Finally, classification by partial least squares discriminant analysis (PLS-DA) was excellent, and 34 out of the 47 proteins were critical for differentiation, confirming the potential of the methodology to obtain a reliable classification of quinoa grains based on protein fingerprinting

In vitro antitumor and hypotensive activity of peptides from olive seeds

Peptides with molecular weights below 3 kDa from the hydrolysis of olive seed proteins with Thermolysin (OS-3 kDa) have demonstrated a high in vitro hypotensive effect. This fraction has been further fractionated by semipreparative RP-HPLC to obtain 8 fractions. ACE inhibitor capacity of fractions was evaluated observing the highest capacity in fraction F5. Peptides in fraction F5 were identified by RP-HPLC- and HILIC-ESI-Q-ToF and cytotoxic effect was assessed in different cell lines. Peptide LLPSY, present in this faction, was synthesized and characterized. Despite antihypertensive capacity was not as high as in fraction F5, a significant anti-proliferative capacity on two different cancer cell lines was observed. Additional studies to assess antitumor activity confirmed that this peptide showed capability to increase the adhesion capacity of tumor cells, to decrease the migration capacity of cancer cells, and to arrest cell cycle on S phase

Classification of quinoa varieties based on protein fingerprinting by capillary electrophoresis with ultraviolet absorption diode array detection and advanced chemometrics

Quinoa (Chenopodium quinoa Willd.) is an andean grain with exceptional nutritional properties that has been progressively introduced in western countries as a protein-rich super food with a broad amino acid spectrum. Quinoa is consumed as whole grain, but it is also milled to produce high-value flour, which is susceptible to adulteration. Therefore, there is a growing interest in developing novel analytical methods to get further information about quinoa at the chemical level. In this study, we developed a rapid and simple capillary electrophoresis-ultraviolet absorption diode array detection (CE-UV-DAD) method to obtain characteristic multiwavelength electrophoretic profiles of soluble protein extracts from different quinoa grain varieties. Then, advanced chemometric methods (i.e. multivariate curve resolution alternating least squares, MCR-ALS, followed by principal component analysis, PCA, and partial least squares discriminant analysis, PLS-DA) were applied to deconvolute the components present in the electropherograms and classify the quinoa varieties according to their differential protein composition

A Proteomics Data Mining Strategy for the Identification of Quinoa Grain Proteins with Potential Immunonutritional Bioactivities

Quinoa proteins are attracting global interest for their wide amino acid profile and as a promising source for the development of biomedical treatments, including those against immunemediated diseases. However, information about the bioactivity of quinoa proteins is scarce. In this study, a quinoa grain proteome map obtained by label-free mass spectrometry-based shotgun proteomics was investigated for the identification of quinoa grain proteins with potential immunonutritional bioactivities, including those related to cancer. After carefully examining the sequence similarities of the 1211 identified quinoa grain proteins against already described bioactive proteins from other plant organisms, 71, 48, and 3 of them were classified as antimicrobial peptides (AMPs), oxidative stress induced peptides (OSIPs), and serine-type protease inhibitors (STPIs), respectively, suggesting their potential as immunomodulatory, anti-inflammatory, and anticancer agents. In addition, data interpretation using Venn diagrams, heat maps, and scatterplots revealed proteome similarities and differences with respect to the AMPs, OSIPs, and STPIs, and the most relevant bioactive proteins in the predominant commercial quinoa grains (i.e., black, red, white (from Peru), and royal (white from Bolivia)). The presented proteomics data mining strategy allows easy screening for potentially relevant quinoa grain proteins and commercial classes for immunonutrition, as a basis for future bioactivity testing

A modified and automated version of the 'Fluorimetric Detection of Alkaline DNA Unwinding' method to quantify formation and repair of DNA strand breaks

<p>Abstract</p> <p>Background</p> <p>Formation and repair of DNA single-strand breaks are important parameters in the assessment of DNA damage and repair occurring in live cells. The 'Fluorimetric Detection of Alkaline DNA Unwinding (FADU)' method [Birnboim HC, Jevcak JJ. Cancer Res (1981) 41:1889–1892] is a sensitive procedure to quantify DNA strand breaks, yet it is very tedious to perform.</p> <p>Results</p> <p>In order (i) to render the FADU assay more convenient and robust, (ii) to increase throughput, and (iii) to reduce the number of cells needed, we have established a modified assay version that is largely automated and is based on the use of a liquid handling device. The assay is operated in a 96-well format, thus greatly increasing throughput. The number of cells required has been reduced to less than 10,000 per data point. The threshold for detection of X-ray-induced DNA strand breaks is 0.13 Gy. The total assay time required for a typical experiment to assess DNA strand break repair is 4–5 hours.</p> <p>Conclusion</p> <p>We have established a robust and convenient method measuring of formation and repair of DNA single-strand breaks in live cells. While the sensitivity of our method is comparable to current assays, throughput is massively increased while operator time is decreased.</p

DNA hydroxymethylation levels are altered in blood cells from Down syndrome persons enrolled in the MARK-AGE project

Down syndrome (DS) is caused by the presence of part or an entire extra copy of chromosome 21, a phenomenon that can cause a wide spectrum of clinically defined phenotypes of the disease. Most of the clinical signs of DS are typical of the ageing process including dysregulation of immune system. Beyond the causative genetic defect, DS persons display epigenetic alterations, particularly aberrant DNA methylation patterns that can contribute to the heterogeneity of the disease. In the present work we investigated the levels of 5-hydroxymethylcytosine (5hmC) and of the TET dioxygenase enzymes, which are involved in DNA demethylation processes and are often deregulated in pathological conditions as well as in ageing. Analyses were carried out on peripheral blood mononuclear cells of DS volunteers enrolled in the context of the MARK-AGE study, a large-scale cross-sectional population study with subjects representing the general population in eight European countries. We observed a decrease of 5hmC, TET1 and other components of the DNA methylation/demethylation machinery in DS subjects, indicating that aberrant DNA methylation patterns in DS, which may have consequences on the transcriptional status of immune cells, may be due to a global disturbance of methylation control in DS

Analysis of serum transthyretin by on-line immunoaffinity solid-phase extraction capillary electrophoresis mass spectrometry using magnetic beads

In this paper, an on-line immunoaffinity solid-phase extraction capillary electrophoresis mass spectrometry (IA-SPE-CE-MS) method using magnetic beads (MBs) is described for the analysis of serum transthyretin (TTR), which is a protein related to different types of amyloidosis. First, purification of TTR from serum was investigated by off-line immunoprecipitation and CE-MS. The suitability of three Protein A (ProA) MBs (Protein A Ultrarapid AgaroseTM (UAPA), Dynabeads® Protein A (DyPA) and SiMAG-Protein A (SiPA)) and AffiAmino Ultrarapid AgaroseTM (UAAF) MBs to prepare an IA sorbent with a polyclonal antibody (Ab) against TTR, was studied. In all cases results were repeatable and it was possible the identification and the quantitation of the relative abundance of the 6 most abundant TTR proteoforms. Although recoveries were the best with UAPA MBs, UAAF MBs were preferred for on-line immunopurification because Ab was not eluted from the MBs. Under the optimised conditions with standards in IA-SPE-CE-MS, microcartridge lifetime (>20 analyses/day) and repeatability (2.9 and 4.3 % RSD for migration times and peak areas) were good, the method was linear between 5- 25 µg·mL-1 and limit of detection (LOD) was around 1 µg·mL-1 (25 times lower than by CE-MS, 25 µg·mL-1). A simple off-line sample pretreatment based on precipitation of the most abundant proteins with 5% (v/v) of phenol was necessary to clean-up serum samples. The potential of the on-line method to screen for familial amyloidotic polyneuropathy type I (FAP-I), which is the most common hereditary systemic amyloidosis, was demonstrated analysing serum samples from healthy controls and FAP-I patients