Documenting adaptations to an evidence-based intervention in 58 resource-variable pediatric oncology hospitals across implementation phases.

Background: Adaptation of evidence-based interventions (EBIs) often occurs when implemented in new local contexts and settings. It is unclear, however, during which phase of implementation adaptations are most frequently made and how these changes may impact the fidelity, effectiveness, and sustainability of the EBI. Pediatric Early Warning Systems (PEWS) are EBIs for early identification of deterioration in hospitalized children with cancer.

Connecting Clinical Capacity and Intervention Sustainability in Resource-Variable Pediatric Oncology Centers in Latin America.

Clinical capacity for sustainability, or the clinical resources needed to sustain an evidence-based practice, represent proximal determinants that contribute to intervention sustainment. We examine the relationship between clinical capacity for sustainability and sustainment of PEWS, an evidence-based intervention to improve outcomes for pediatric oncology patients in resource-variable hospitals. We conducted a cross-sectional survey among Latin American pediatric oncology centers participating in Proyecto Escala de Valoración de Alerta Temprana (EVAT), an improvement collaborative to implement Pediatric Early Warning Systems (PEWS).

Effect of paediatric early warning systems (PEWS) implementation on clinical deterioration event mortality among children with cancer in resource-limited hospitals in Latin America: a prospective, multicentre cohort study.

Background: Paediatric early warning systems (PEWS) aid in the early identification of clinical deterioration events in children admitted to hospital. We aimed to investigate the effect of PEWS implementation on mortality due to clinical deterioration in children with cancer in 32 resource-limited hospitals across Latin America.

Methods: Proyecto Escala de Valoración de Alerta Temprana (Proyecto EVAT) is a quality improvement collaborative to implement PEWS in hospitals providing childhood cancer care.

Impact of hospital characteristics on implementation of a Pediatric Early Warning System in resource-limited cancer hospitals.

Background: Pediatric Early Warning Systems (PEWS) aid in identification of deterioration in hospitalized children with cancer but are underutilized in resource-limited settings. Proyecto EVAT is a multicenter quality improvement (QI) collaborative in Latin America to implement PEWS. This study investigates the relationship between hospital characteristics and time required for PEWS implementation.

Clinical and organizational risk factors for mortality during deterioration events among pediatric oncology patients in Latin America: A multicenter prospective cohort.

Background: Hospitalized pediatric hematology-oncology (PHO) patients have frequent clinical deterioration events (CDE) requiring intensive care unit (ICU) admission, particularly in resource-limited settings. The objective of this study was to describe CDEs in hospitalized PHO patients in Latin America and to identify event-level and center-level risk factors for mortality.

Methods: In 2017, the authors implemented a prospective registry of CDEs, defined as unplanned transfers to a higher level of care, use of ICU-level interventions on the floor, or nonpalliative floor deaths, in 16 PHO centers in 10 countries.

Global Retinoblastoma Presentation and Analysis by National Income Level.

Importance: Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale.

Identification of Tyrosine and Nitrotyrosine with a Mixed-Mode Solid-Phase Extraction Cleanup Followed by Liquid Chromatography-Electrospray Time-of-Flight Mass Spectrometry in Plants.

In higher plants, there is a growing interest in the study of protein tyrosine nitration (NOTyr) as well as the identification of in vivo nitrated proteins. Different methods have been developed for identifying nitrotyrosine in biological samples. However, these analyses are difficult because tyrosine nitration is a very low-abundance posttranslational protein modification (PTM) and the lack of efficient enrichment methods for detection.

Nitro-linolenic acid is a nitric oxide donor.

Nitro-fatty acids (NO2-FAs), which are the result of the interaction between reactive nitrogen species (RNS) and non-saturated fatty acids, constitute a new research area in plant systems, and their study has significantly increased. Very recently, the endogenous presence of nitro-linolenic acid (NO2-Ln) has been reported in the model plant Arabidopsis thaliana. In this regard, the signaling role of this molecule has been shown to be key in setting up a defense mechanism by inducing the chaperone network in plants.

Quantification and Localization of S-Nitrosothiols (SNOs) in Higher Plants.

S-nitrosothiols (SNOs) are a family of molecules produced by the reaction of nitric oxide (NO) with -SH thiol groups present in the cysteine residues of proteins and peptides caused by a posttranslational modification (PTM) known as S-nitrosylation (strictly speaking S-nitrosation) that can affect the cellular function of proteins. These molecules are a relatively more stable form of NO and consequently can act as a major intracellular NO reservoir and, in some cases, as a long-distance NO signal. Additionally, SNOs can be transferred between small peptides and protein thiol groups through S-transnitrosylation mechanisms.

A dual system formed by the ARC and NR molybdoenzymes mediates nitrite-dependent NO production in Chlamydomonas.

Nitric oxide (NO) is a relevant signal molecule involved in many plant processes. However, the mechanisms and proteins responsible for its synthesis are scarcely known. In most photosynthetic organisms NO synthases have not been identified, and Nitrate Reductase (NR) has been proposed as the main enzymatic NO source, a process that in vitro is also catalysed by other molybdoenzymes.

Dual regulation of cytosolic ascorbate peroxidase (APX) by tyrosine nitration and S-nitrosylation.

Post-translational modifications (PTMs) mediated by nitric oxide (NO)-derived molecules have become a new area of research, as they can modulate the function of target proteins. Proteomic data have shown that ascorbate peroxidase (APX) is one of the potential targets of PTMs mediated by NO-derived molecules. Using recombinant pea cytosolic APX, the impact of peroxynitrite (ONOO-) and S-nitrosoglutathione (GSNO), which are known to mediate protein nitration and S-nitrosylation processes, respectively, was analysed.

Vinyl sulfone silica: application of an open preactivated support to the study of transnitrosylation of plant proteins by S-nitrosoglutathione.

Background: S-nitrosylaton is implicated in the regulation of numerous signaling pathways with a diversity of regulatory roles. The high lability of the S-NO bond makes the study of proteins regulated by S-nitrosylation/denitrosylation a challenging task and most studies have focused on already S-nitrosylated proteins. We hypothesize that: i) S-nitrosoglutathione (GSNO) transnitrosylation is a feasible mechanism to account for the physiological S-nitrosylation of rather electropositive sulfur atoms from proteins, ii) affinity chromatography is a suitable approach to isolate proteins that are prone to undergo S-transnitrosylation and iii) vinyl sulfone silica is a suitable chromatographic bead.

Tyrosine nitration provokes inhibition of sunflower carbonic anhydrase (β-CA) activity under high temperature stress.

Protein tyrosine nitration is a post-translational modification (PTM) mediated by reactive nitrogen species (RNS) and it is a new area of research in higher plants. Previously, it was demonstrated that the exposition of sunflower (Helianthus annuus L.) seedlings to high temperature (HT) caused both oxidative and nitrosative stress.

Determination of nitrotyrosine in Arabidopsis thaliana cell cultures with a mixed-mode solid-phase extraction cleanup followed by liquid chromatography time-of-flight mass spectrometry.

In this work, a method for the determination of trace nitrotyrosine (NO(2)Tyr) and tyrosine (Tyr) in Arabidopsis thaliana cell cultures is proposed. Due to the complexity of the resulting extracts after protein precipitation and enzymatic digestion and the strong electrospray signal suppression displayed in the detection of both Tyr and NO(2)Tyr from raw A. thaliana cell culture extracts, a straightforward sample cleanup step was proposed.

High temperature triggers the metabolism of S-nitrosothiols in sunflower mediating a process of nitrosative stress which provokes the inhibition of ferredoxin-NADP reductase by tyrosine nitration.

High temperature (HT) is considered a major abiotic stress that negatively affects both vegetative and reproductive growth. Whereas the metabolism of reactive oxygen species (ROS) is well established under HT, less is known about the metabolism of reactive nitrogen species (RNS). In sunflower (Helianthus annuus L.

Functional analysis of superoxide dismutases (SODs) in sunflower under biotic and abiotic stress conditions. Identification of two new genes of mitochondrial Mn-SOD.

Superoxide dismutases (SODs) are a family of metalloenzymes that catalyse the disproportionation of superoxide radicals into hydrogen peroxide and oxygen. In sunflower (Helianthus annuus L.) seedlings, two new Mn-SOD isozymes, designated as I and II, were identified.

Mechanical wounding induces a nitrosative stress by down-regulation of GSNO reductase and an increase in S-nitrosothiols in sunflower (Helianthus annuus) seedlings.

Nitric oxide (NO) and related molecules such as peroxynitrite, S-nitrosoglutathione (GSNO), and nitrotyrosine, among others, are involved in physiological processes as well in the mechanisms of response to stress conditions. In sunflower seedlings exposed to five different adverse environmental conditions (low temperature, mechanical wounding, high light intensity, continuous light, and continuous darkness), key components of the metabolism of reactive nitrogen species (RNS) and reactive oxygen species (ROS), including the enzyme activities L-arginine-dependent nitric oxide synthase (NOS), S-nitrosogluthathione reductase (GSNOR), nitrate reductase (NR), catalase, and superoxide dismutase, the content of lipid hydroperoxide, hydrogen peroxide, S-nitrosothiols (SNOs), the cellular level of NO, GSNO, and GSNOR, and protein tyrosine nitration [nitrotyrosine (NO(2)-Tyr)] were analysed. Among the stress conditions studied, mechanical wounding was the only one that caused a down-regulation of NOS and GSNOR activities, which in turn provoked an accumulation of SNOs.

Mitochondrial 1-Cys-peroxiredoxin/thioredoxin system protects manganese-containing superoxide dismutase (Mn-SOD) against inactivation by peroxynitrite in Saccharomyces cerevisiae.

Peroxynitrite is a reactive nitrogen species that can mediate protein tyrosine nitration, inactivating many proteins. We show that yeast mitochondrial peroxiredoxin (Prx1p), which belongs to the group 1-Cys-Prx, has thioredoxin-dependent peroxynitrite reductase activity. This activity was characterised in vitro with the recombinant mitochondrial Prx1p, the thioredoxin reductase Trr2p and the thioredoxin Trx3p, using a generator of peroxynitrite (SIN-1).

Protein targets of tyrosine nitration in sunflower (Helianthus annuus L.) hypocotyls.

Tyrosine nitration is recognized as an important post-translational protein modification in animal cells that can be used as an indicator of a nitrosative process. However, in plant systems, there is scant information on proteins that undergo this process. In sunflower hypocotyls, the content of tyrosine nitration (NO(2)-Tyr) and the identification of nitrated proteins were studied by high-performance liquid chromatography with tandem mass spectrometry (LC-MS/MS) and proteomic approaches, respectively.

Involvement of reactive nitrogen and oxygen species (RNS and ROS) in sunflower-mildew interaction.

Nitric oxide (.NO) has been shown to participate in plant response against pathogen infection; however, less is known of the participation of other NO-derived molecules designated as reactive nitrogen species (RNS). Using two sunflower (Helianthus annuus L.

Metabolism of reactive nitrogen species in pea plants under abiotic stress conditions.

Nitric oxide (*NO) is a key signaling molecule in different physiological processes of animals and plants. However, little is known about the metabolism of endogenous *NO and other reactive nitrogen species (RNS) in plants under abiotic stress conditions. Using pea plants exposed to six different abiotic stress conditions (high light intensity, low and high temperature, continuous light, continuous dark and mechanical wounding), several key components of the metabolism of RNS including the content of *NO, S-nitrosothiols (RSNOs) and nitrite plus nitrate, the enzyme activities of l-arginine-dependent nitric oxide synthase (NOS) and S-nitrosogluthathione reductase (GSNOR), and the profile of protein tyrosine nitration (NO(2)-Tyr) were analyzed in leaves.

Localization of S-nitrosothiols and assay of nitric oxide synthase and S-nitrosoglutathione reductase activity in plants.

The study of the metabolism of nitric oxide and other reactive nitrogen species (RNS) in plants has been the subject of intensive work in the last decade due to the relevance of these molecules in the physiology and biochemistry of plants. However, there are still many methodological limitations in the specific and accurate determination and localization of RNS. This chapter describes several biochemical and cellular methods demonstrated to be useful for this purpose in different plant tissues.

Nitrosative stress in plants.

Nitrosative stress has become a usual term in the physiology of nitric oxide in mammalian systems. However, in plants there is much less information on this type of stress. Using olive leaves as experimental model, the effect of salinity on the potential induction of nitrosative stress was studied.

The dehydrogenase-mediated recycling of NADPH is a key antioxidant system against salt-induced oxidative stress in olive plants.

NADPH is an important molecule in the redox balance of the cell. In this paper, using olive tissue cultures as a model of the function of the NADPH-generating dehydrogenases in the mechanism of oxidative stress induced by severe salinity conditions was studied. When olive (Olea europaea) plants were grown with 200 mM NaCl, a 40% reduction in leaf fresh weight was produced.

The expression of different superoxide dismutase forms is cell-type dependent in olive (Olea europaea L.) leaves.

Superoxide dismutase (SOD) is a key antioxidant enzyme present in prokaryotic and eukaryotic cells as a first line of defense against the accumulation of superoxide radicals. In olive leaves, the SOD enzymatic system was characterized and was found to be comprised of three isozymes, an Mn-SOD, an Fe-SOD and a CuZn-SOD. Transcript expression analysis of whole leaves showed that the three isozymes represented 82, 17 and 0.