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Tumor angiogenesis isrequired for tumor development and growth, and is regulatedby several factors including ROS. [H.sub.2][O.sub.2] is a ROS with an important role in cell signaling, but how [H.sub.2][O.sub.2] regulates tumor angiogenesis isstill poorly understood. We have xenografted tumor cells with altered levels of [H.sub.2][O.sub.2] by catalase overexpression into zebrafish embryos to study redox-induced tumor neovascularization. We found that vascular recruitment and invasion were impaired if catalase was overex-pressed. In addition, the overexpression of catalase altered the transcriptional levels of several angiogenesis-related factors in tumor cells, including TIMP-3 and THBS1. These two anti-angiogenic factors were found to be [H.sub.2][O.sub.2]-regulated by two different mechanisms: TIMP-3 expression in a cell-autonomous manner; and, THBS1 expression that was non-cell-autonomous. Our work shows that intracellular [H.sub.2][O.sub.2] regulates the expression of angiogenic factors and the formation of a vessel network. Understanding the molecular mechanisms that govern this multifunctional effectof[H.sub.2][O.sub.2] on tumor angiogenesis could beimportant for the development of more efficient anti-angiogenic therapies. Key words: hydrogen peroxide, zebrafish, tumor angiogenesis, catalase, TIMP-3, THBS1. Resume : L'angiogenese tumorale est necessaire au developpement et a la croissance des tumeurs et elle est regulee par plusieurs facteurs dont les derives reactifs d'oxygene (DRO). Le peroxyde d'hydrogene ([H.sub.2][O.sub.2]) est un DRO qui joue un role important dans la signalisation cellulaire, mais on comprend encore mal comment le [H.sub.2][O.sub.2] regule l'angiogenese tumorale. Les auteurs ont effectue des xenogreffes de cellules tumorales dont les niveaux de [H.sub.2][O.sub.2] sont modifies par la surexpression de la catalase dans des embryons de poisson-zebre afin d'etudier la neovascularisation tumorale induite par la redox. Ils ont trouve que le recrutement et l'invasion par les vaisseaux etaient attenues par la surexpression de la catalase. De plus, la surexpression de la catalase modifiait les niveaux de transcription de plusieurs facteurs relies a l'angiogenese dans les cellules tumorales dont TIMP-3 et THBS1. Il est apparu que ces deux facteurs anti-angiogeniques etaient regules par le [H.sub.2][O.sub.2] au moyen de deux mecanismes differents : l'expression de TIMP-3 est autonome a la cellule alors que l'expression de THBS1 est non-autonome. Le travail des auteurs montre que le [H.sub.2][O.sub.2] intracellulaire regule l'expression de facteurs angiogeniques et la formation d'un reseau vasculaire. La comprehension des mecanismes moleculaires qui gouvernent cet effet multifonctionnel du [H.sub.2][O.sub.2] sur l'angiogenese tumorale pourrait etre importante au developpement de nouvelles therapies anti-angiogeniques plus efficaces. [Traduit par la Redaction] Mots-cles : peroxyde d'hydrogene, poisson-zebre, angiogenese tumorale, catalase, TIMP-3, THBS1., Introduction Tumors originate from cellular masses with unchecked growth. As cells multiply, both the oxygen and nutrient supplies needed for cell survival and proliferation become limiting, leading to equilibrium between [...]

In the present study, the rheological and baking properties of blends containing bread wheat flour and durum wheat semolina were analyzed. Two bread wheat varieties (Almansor, Pirana), three durum wheat varieties (Celta, Hélvio, Marialva) and two replacement levels (25 and 60%) were used to determine differences in dough behaviour and bread properties. These varieties showed difference in their properties, once they have different allelic composition for the most determinant loci to quality (Glu-1 in bread wheat and Glu-3 in durum wheat). The addition of durum wheat semolina to Almansor flour had a deleterious effect on the main all quality parameters. The dough stability and loaf volume of Pirana flour (weak bread wheat) could be improved when blends were made with Hélvio's semolina. The replacement level of durum wheat in both types of blends increased alveograph P/L and yellowish crumb colour but decreased alveograph deformation energy W and loaf volume of blends with Almansor. This study showed the possibility of making bread with acceptable characteristics using mixtures of bread and durum wheats, although, can cause lower bread volume. [ABSTRACT FROM AUTHOR]

Bread wheat ( Triticum aestivum ) is a major crop worldwide, and it is highly susceptible to heat. In this work, grain production and composition were evaluated in Portuguese T. aestivum germplasm (landraces and commercial varieties), which was subjected to heat after anthesis (grain filling stage). Heat increased the test weight (TW) in Nabão, Grécia and Restauração, indicating an improved flour-yield potential. Mocho de Espiga Branca (MEB) and Transmontano (T94) showed higher thousand-kernel weight (TKW). Gentil Rosso presented increased soluble sugars, which are yeast substrates in the bread-making process. Ardila stood out for its protein increase under heat. Overall SDS was unaffected by higher temperature, but increased in T94, indicating a better dough elasticity for bread-making purposes. Under heat, lipid content was maintained in most genotypes, being endogenous fatty acids (FAs) key players in fresh bread quality. Lipid unsaturation, evaluated through the double bond index (DBI), also remained unaffected in most genotypes, suggesting a lower flour susceptibility to lipoperoxidation. In Grécia, heat promoted a higher abundance of monounsaturated oleic (C18:1) and polyunsaturated linoleic (C18:2) acids, which are essential fatty acids in the human diet. This work highlighted a great variability in most parameters both under control conditions or in response to heat during grain filling. Cluster analysis of traits revealed a lower susceptibility to heat during grain filling in Ardila, Restauração, and Ruivo, in contrast to MEQ, which seems to be more differentially affected at this stage. Characterization and identification of more favorable features under adverse environments may be relevant for agronomic, industrial, or breeding purposes, in view of a better crop adaptation to changing climate and an improved crop sustainability in agricultural systems more prone to heat stress.

Ribosomal Protein SA (RPSA), a component of the 40S ribosomal subunit, was identified as a H2O2 target in HeLa cells [1]. In order to analyze the intracellular localization of RPSA in different redox states we overexpressed wild-type RPSA (RPSAwt) or RPSA containing two cysteine to serine residue substitutions at positions 148 and 163 (RPSAmut) in HeLa cells. The transfected cells were exposed to H2O2 or N-acetylcysteine (NAC) and RPSA subcellular localization was assessed by immunofluorescence in permeabilized cells. In addition, co-immunofluorescence for RPSA and Ribosomal Protein S6 (RPS6) was performed in cells overexpressing RPSAwt or RPSAmut. Finally, the ribosomal expression of endogenous RPSA in the presence or absence of H2O2 was analyzed by Western blot. The data presented in this work is related to the research article entitled "Hydrogen peroxide regulates cell adhesion through the redox sensor RPSA" [1].