The dynamics and determinants of specific systemic and mucosal antibody responses to SARS-CoV-2 in three adult cohorts in the Ecuadorian Andes: a study protocol.

Introduction: There are limited longitudinal data on the systemic and mucosal antibody responses to SARS-CoV-2 from Latin America, a region severely affected by COVID-19, and where vaccine strategies have been implemented during the evolving pandemic.

Objective: To evaluate determinants of seroprevalence and changes in levels of anti-SARS-CoV-2 antibodies longitudinally in adults with different levels of exposure to SARS-CoV-2 (defined as low, medium, and high based on presumed occupational risk), in two Andean cities in Ecuador.

Methods: Longitudinal cohort study of 1,000 adults aged 18 years and older with questionnaire data and sample collection done at 0, 3, 6, and 12 months during the period 2020-2023.

A systemic framework of energy efficiency in schools: experiences from six European countries.

Schools are complex physical and social institutions within national education systems. They account for significant energy consumption and like other buildings can demonstrate inefficient patterns of energy use. Poor energy performance of educational facilities is an intricate issue driven by complex causality of interconnected and dynamic factors.

Behavioural intention of hand hygiene compliance in an average Ecuadorian hospital.

Objective: This study aimed to characterize hand hygiene behavioural intention by hospital services clusters in a medium-sized hospital in an Ecuadorian city.

Methods: This is a cross-sectional study based on the World Health Organization Hand Hygiene Knowledge Questionnaire for Health-Care Workers. The responses on hand hygiene behavioural intention for the Five Moments for hand hygiene according to the World Health Organization were recorded in three categories: before patient contact, before and after sterile technique and management of body fluids, and after contact with the environment of the patient.

Prospective study of factors associated with asthma attack recurrence (ATTACK) in children from three Ecuadorian cities during COVID-19: a study protocol.

Introduction: Asthma is a growing health problem in children in marginalised urban settings in low-income and middle-income countries. Asthma attacks are an important cause of emergency care attendance and long-term morbidity. We designed a prospective study, the Asthma Attacks study, to identify factors associated with recurrence of asthma attacks (or exacerbations) among children and adolescents attending emergency care in three Ecuadorian cities.

Medical specialist distributions in Ecuador: a geographical and temporal analysis of data from 2000 to 2017.

Background: Knowledge of medical specialists' numbers and geographical distribution are essential for planning health services and health workforce supply. However, although the distribution of physicians is a significant concern for society and policymakers in Ecuador, no studies have evaluated the distribution of specialists in the country. This study aimed to explore the geographical and temporal distribution of medical specialists in Ecuador over 18 years from 2000 to 2017 and analyse its implications for health planning and medical training.

Health workers' perspectives on asthma care coordination between primary and specialised healthcare in the COVID-19 pandemic: a protocol for a qualitative study in Ecuador and Brazil.

Introduction: Asthma is a common long-term disorder and strategies to improve asthma control are still a challenge. Integrated delivery of health systems is critical for effective asthma care: there is limited information on experiences of care coordination for asthma from Latin America, especially on perspectives of health personnel and in the context of the COVID-19 pandemic.

Methods And Analysis: This protocol details a qualitative approach to analyse health workers' perspectives of healthcare coordination for asthma control during COVID-19 pandemic in Ecuador and Brazil, at primary and specialised levels, through in-depth semistructured interviews using a video communications platform.

The surface topography of silicone breast implants mediates the foreign body response in mice, rabbits and humans.

Silicone is widely used in chronic implants and is generally perceived to be safe. However, textured breast implants have been associated with immune-related complications, including malignancies. Here, by examining for up to one year the foreign body response and capsular fibrosis triggered by miniaturized or full-scale clinically approved breast implants with different surface topography (average roughness, 0-90 μm) placed in the mammary fat pads of mice or rabbits, respectively, we show that surface topography mediates immune responses to the implants.

Age-dependent seroprevalence of dengue and chikungunya: inference from a cross-sectional analysis in Esmeraldas Province in coastal Ecuador.

Objectives: There are few population-based estimates for prevalence of past exposure to dengue and chikungunya viruses despite common epidemiological features. Here, we have developed a novel statistical method to study patterns of age-dependent prevalence of immunity in a population following exposures to two viruses which share similar epidemiological features including mode of transmission and induction of long-lasting immunity. This statistical technique accounted for sociodemographic characteristics associated with individuals and households.

Uremic toxins promote accumulation of oxidized protein and increased sensitivity to hydrogen peroxide in endothelial cells by impairing the autophagic flux.

Chronic kidney disease (CKD) is associated with high mortality rates, mainly due to cardiovascular diseases (CVD). Uremia has been considered a relevant risk factor for CVD in CKD patients, since uremic toxins (UTs) promote systemic and vascular inflammation, oxidative stress and senescence. Here, we demonstrate that uremic toxins indoxyl sulfate (IxS), p-cresyl sulfate (pCS) and indole acetic acid (IAA) are incorporated by human endothelial cells and inhibit the autophagic flux, demonstrated by cellular p62 accumulation.

Biochemistry of Peroxynitrite and Protein Tyrosine Nitration.

Peroxynitrite is a short-lived and reactive biological oxidant formed from the diffusion-controlled reaction of the free radicals superoxide (O) and nitric oxide (NO). In this review, we first analyze the biochemical evidence for the formation of peroxynitrite in vivo and the reactions that lead to it. Then, we describe the principal reactions that peroxynitrite undergoes with biological targets and provide kinetic and mechanistic details.

Insulin-dependent metabolic and inotropic responses in the heart are modulated by hydrogen peroxide from NADPH-oxidase isoforms NOX2 and NOX4.

Rationale: Hydrogen peroxide (HO) is a stable reactive oxygen species (ROS) that has long been implicated in insulin signal transduction in adipocytes. However, HO's role in mediating insulin's effects on the heart are unknown.

Objective: We investigated the role of HO in activating insulin-dependent changes in cardiac myocyte metabolic and inotropic pathways.

Multicystic seminal vesicle with ipsilateral renal agenesis: two cases of Zinner syndrome.

The association of ipsilateral renal agenesis and cystic seminal vesicle is a rare congenital syndrome described by Zinner in 1914. The cases of two patients with this syndrome are presented, one of them associated with infertility, the other with cryptorchidism and testicular pain. A brief review of the literature is undertaken, regarding the main clinical and imaging implications, and the developmental anomalies that are involved in this unusual congenital anomaly are analyzed.

Spontaneous intramural esophageal dissection: an unusual onset of eosinophilic esophagitis.

A 35-year-old man, with a history of rhinitis, eczema and a dubious achalasia was admitted due to chest pain and sialorrhea. Upper endoscopy showed a little hole and a narrowing of the distal esophagus. A CT-scan with oral contrast exposed a discontinuity of the lumen of the middle third of the esophagus and a dissection of submucosal space 16 cm long.

Nitric oxide diffusion to red blood cells limits extracellular, but not intraphagosomal, peroxynitrite formation by macrophages.

Macrophage-derived nitric oxide ((•)NO) participates in cytotoxic mechanisms against diverse microorganisms and tumor cells. These effects can be mediated by (•)NO itself or (•)NO-derived species such as peroxynitrite formed by its diffusion-controlled reaction with NADPH oxidase-derived superoxide radical anion (O(2)(•-)). In vivo, the facile extracellular diffusion of (•)NO as well as different competing consumption routes limit its bioavailability for the reaction with O(2)(•-) and, hence, peroxynitrite formation.

Cassava starch films containing acetylated starch nanoparticles as reinforcement: Physical and mechanical characterization.

This paper reports the use of acetylated starch nanoparticles (NPAac) as reinforcement in thermoplastic starch films. NPAac with an average size of approximately 500 nm were obtained by nanoprecipitation. Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA) indicated that NPAac are more thermally stable and essentially amorphous when compared with acetylated starch.

Central role for hydrogen peroxide in P2Y1 ADP receptor-mediated cellular responses in vascular endothelium.

ADP activates a family of cell surface receptors that modulate signaling pathways in a broad range of cells. ADP receptor antagonists are widely used to treat cardiovascular disease states. These studies identify a critical role for the stable reactive oxygen species hydrogen peroxide (H2O2) in mediating cellular responses activated by the G protein-coupled P2Y1 receptor for ADP.

Caveolin-1 is a critical determinant of autophagy, metabolic switching, and oxidative stress in vascular endothelium.

Caveolin-1 is a scaffolding/regulatory protein that interacts with diverse signaling molecules. Caveolin-1(null) mice have marked metabolic abnormalities, yet the underlying molecular mechanisms are incompletely understood. We found the redox stress plasma biomarker plasma 8-isoprostane was elevated in caveolin-1(null) mice, and discovered that siRNA-mediated caveolin-1 knockdown in endothelial cells promoted significant increases in intracellular H₂O₂.

In vivo imaging of nitric oxide and hydrogen peroxide in cardiac myocytes.

Nitric oxide (NO) and hydrogen peroxide (H2O2) are synthesized within cardiac myocytes, and both molecules play key roles in modulating cardiovascular responses. However, the interconnections between NO and H2O2 in cardiac myocyte signaling have not been properly understood. Adult mouse cardiac myocytes represent an informative model for the study of receptor-modulated signaling pathways involving reactive oxygen species and reactive nitrogen species.

Critical role of hydrogen peroxide signaling in the sequential activation of p38 MAPK and eNOS in laminar shear stress.

Laminar shear stress (LSS) is a protective hemodynamic regulator of endothelial function and limits the development of atherosclerosis and other vascular wall diseases related to pathophysiological generation of reactive oxygen species. LSS activates several endothelial signaling responses, including the activation of MAPKs and eNOS. Here, we explored the mechanisms of activation of these key endothelial signaling pathways.

Antioxidant activity of uruguayan propolis. In vitro and cellular assays.

The antioxidant capacity of propolis from the southern region of Uruguay was evaluated using in vitro as well as cellular assays. Free radical scavenging capacity was assessed by ORAC, obtaining values significantly higher than those of other natural products (8000 μmol Trolox equiv/g propolis). ORAC values correlated well with total polyphenol content (determined by Folin-Ciocalteu method) and UV absorption.

Cyclosporine A-induced nitration of tyrosine 34 MnSOD in endothelial cells: role of mitochondrial superoxide.

Aims: Cyclosporine A (CsA) has represented a fundamental therapeutic weapon in immunosuppression for the past three decades. However, its clinical use is not devoid of side effects, among which hypertension and vascular injury represent a major drawback. Endothelial cells are able to generate reactive oxygen and nitrogen species upon exposure to CsA, including formation of peroxynitrite.

Peroxynitrite inhibits electron transport on the acceptor side of higher plant photosystem II.

Peroxynitrite is a strong oxidant that has been proposed to form in chloroplasts. The interaction between peroxynitrite and photosystem II (PSII) has been investigated to determine whether this oxidant could be a hazard for PSII. Peroxynitrite is shown to inhibit oxygen evolution in PSII membranes in a dose-dependent manner.