Venom-microbiomics of eight species of Neotropical spiders from the Theraphosidae family.

Aim: Tarantulas are one of the largest predatory arthropods in tropical regions. Tarantulas though not lethal to humans, their venomous bite kills small animals and insect upon which they prey. To understand the abiotic and biotic components involved in Neotropical tarantula bites, we conducted a venom-microbiomics study in eight species from Costa Rica.

Improvement in cardiac function and regional LV strain following intramyocardial injection of a theranostic hydrogel early postmyocardial infarction in a porcine model.

Myocardial infarction (MI) is often complicated by left ventricular (LV) remodeling and heart failure. We evaluated the feasibility of a multimodality imaging approach to guide delivery of an imageable hydrogel and assessed LV functional changes with therapy. Yorkshire pigs underwent surgical occlusions of branches of the left anterior descending and/or circumflex artery to create an anterolateral MI.

Production of selenium nanoparticles occurs through an interconnected pathway of sulphur metabolism and oxidative stress response in Pseudomonas putida KT2440.

The soil bacterium Pseudomonas putida KT2440 has been shown to produce selenium nanoparticles aerobically from selenite; however, the molecular actors involved in this process are unknown. Here, through a combination of genetic and analytical techniques, we report the first insights into selenite metabolism in this bacterium. Our results suggest that the reduction of selenite occurs through an interconnected metabolic network involving central metabolic reactions, sulphur metabolism, and the response to oxidative stress.

Out of the blue: the independent activity of sulfur-oxidizers and diatoms mediate the sudden color shift of a tropical river.

Background: Río Celeste ("Sky-Blue River") is a river located in the Tenorio National Park (Costa Rica) that has become an important hotspot for eco-tourism due to its striking sky-blue color. A previous study indicated that this color is not caused by dissolved chemical species, but by formation of light-scattering aluminosilicate particles at the mixing point of two colorless streams, the acidic Quebrada Agria and the neutral Río Buenavista.

Results: We now present microbiological information on Río Celeste and its two tributaries, as well as a more detailed characterization of the particles that occur at the mixing point.

Fungi with history: Unveiling the mycobiota of historic documents of Costa Rica.

We studied the physicochemical characteristics and mycobiota associated to five key historic documents from Costa Rica, including the Independence Act of Costa Rica from 1821. We used nondestructive techniques (i.e.

Quantification of intramyocardial blood volume using Tc-RBC SPECT/CT: a pilot human study.

Background: Quantification of intramyocardial blood volume (IMBV), the fraction of myocardium that is occupied by blood, is a promising Index to measure microcirculatory functions. In previous large animal SPECT/CT studies injected with Tc-labeled Red Blood Cell (RBC) and validated by ex vivo microCT, we have demonstrated that accurate IMBV can be measured. In this study, we report the data processing methods and results of the first-in-human pilot study.

CineCT platform for in vivo and ex vivo measurement of 3D high resolution Lagrangian strains in the left ventricle following myocardial infarction and intramyocardial delivery of theranostic hydrogel.

Myocardial infarction (MI) produces acute changes in strain and stiffness within the infarct that can affect remote areas of the left ventricle (LV) and drive pathological remodeling. We hypothesized that intramyocardial delivery of a hydrogel within the MI region would lower wall stress and reduce adverse remodeling in Yorkshire pigs (n = 5). Tc-Tetrofosmin SPECT imaging defined the location and geometry of induced MI and border regions in pigs, and in vivo and ex vivo contrast cine computed tomography (cineCT) quantified deformations of the LV myocardium.

Biodeterioration and cellulolytic activity by fungi isolated from a nineteenth-century painting at the National Theatre of Costa Rica.

Living organisms can induce deterioration of cultural heritage. Conservation strategies aimed at avoiding damage and aiding restoration, require a comprehensive knowledge of structure, chemical composition, and identity of microorganisms that colonize artworks. The National Theatre of Costa Rica (NTCR), a building with historic architecture, houses several oil paintings from the nineteenth century, some with visible signs of biodeterioration.

Effect of Hydroxychloroquine on QTc in Patients Diagnosed with COVID-19: A Systematic Review and Meta-Analysis.

Background: Hydroxychloroquine or chloroquine with or without the concomitant use of azithromycin have been widely used to treat patients with SARS-CoV-2 infection, based on early in vitro studies, despite their potential to prolong the QTc interval of patients.

Objective: This is a systematic review and metanalysis designed to assess the effect of hydroxychloroquine with or without the addition of azithromycin on the QTc of hospitalized patients with COVID-19.

Materials And Methods: PubMed, Scopus, Cochrane and MedRxiv databases were reviewed.

Streptomyces sp. M54: an actinobacteria associated with a neotropical social wasp with high potential for antibiotic production.

Streptomyces symbionts in insects have shown to be a valuable source of new antibiotics. Here, we report the genome sequence and the potential for antibiotic production of "Streptomyces sp. M54", an Actinobacteria associated with the eusocial wasp, Polybia plebeja.

Temperature and elemental sulfur shape microbial communities in two extremely acidic aquatic volcanic environments.

Aquatic environments of volcanic origin provide an exceptional opportunity to study the adaptations of microorganisms to early planet life conditions. Here, we characterized the prokaryotic communities and physicochemical properties of seepage sites at the bottom of the Poas Volcano crater and the Agrio River, two geologically related extremely acidic environments located in Costa Rica. Both locations hold a low pH (1.

Anger recall mental stress decreases I-metaiodobenzylguanidine (I-MIBG) uptake and increases heterogeneity of cardiac sympathetic activity in the myocardium in patients with ischemic cardiomyopathy.

Background: Acute psychological stressors such as anger can precipitate ventricular arrhythmias, but the mechanism is incompletely understood. Quantification of regional myocardial sympathetic activity with I-metaiodobenzylguanidine (I-mIBG) SPECT imaging in conjunction with perfusion imaging during mental stress may identify a mismatch between perfusion and sympathetic activity that may exacerbate a mismatch between perfusion and sympathetic activity that could create a milieu of increased vulnerability to ventricular arrhythmia.

Methods: Five men with ischemic cardiomyopathy (ICM), and five age-matched healthy male controls underwent serial I-mIBG and Tc-Tetrofosmin SPECT/CT imaging during an anger recall mental stress task and dual isotope imaging was repeated approximately 1 week later during rest.

Microbial Community Structure Along a Horizontal Oxygen Gradient in a Costa Rican Volcanic Influenced Acid Rock Drainage System.

We describe the geochemistry and microbial diversity of a pristine environment that resembles an acid rock drainage (ARD) but it is actually the result of hydrothermal and volcanic influences. We designate this environment, and other comparable sites, as volcanic influenced acid rock drainage (VARD) systems. The metal content and sulfuric acid in this ecosystem stem from the volcanic milieu and not from the product of pyrite oxidation.

Bocaparvovirus, Erythroparvovirus and Tetraparvovirus in New World Primates from Central America.

Parvoviruses in the genera Bocaparvovirus (HBoV), Erythroparvovirus (B19) and Tetraparvovirus (PARV4) are the only autonomous parvoviruses known to be associated with human and non-human primates based on studies and clinical cases in humans worldwide and non-human primates in Asia and Africa. Here, the presence of these agents with pathogenic potential was assessed by PCR in blood and faeces from 55 howler monkeys, 112 white-face monkeys, 3 squirrel monkeys and 127 spider monkeys in Costa Rica and El Salvador. Overall, 3.

CT perfusion measurement of postictal hypoperfusion: localization of the seizure onset zone and patterns of spread.

Purpose: Seizures are often followed by a period of transient neurological dysfunction and postictal alterations in cerebral blood flow may underlie these symptoms. Recent animal studies have shown reduced local cerebral blood flow at the seizure onset zone (SOZ) lasting approximately 1 h following seizures. Using arterial spin labelling (ASL) MRI, we observed postictal hypoperfusion at the SOZ in 75% of patients.

Mastering the art of epicardial access in cardiac electrophysiology.

Access to the epicardial space is fundamental to several cardiac procedures. While traditional indications include catheter ablation of ventricular arrhythmias and accessory pathways, novel indications include left atrial appendage occlusion, esophageal protection, mapping and ablation during atrial fibrillation procedures, implantation of epicardial pacing leads, and phrenic nerve displacement to facilitate safe ablation of atrial and ventricular arrhythmias. Accessing the epicardial space safely is a major challenge requiring intimate knowledge of cardiac anatomy, extensive training, and expertise.

Brugada Syndrome: Progress in Genetics, Risk Stratification and Management.

Brugada syndrome (BrS) is one of the most common causes of sudden cardiac death in normal structural heart individuals. First characterised in 1992, the global prevalence of BrS is unclear, with estimates placing it at around 0.05% and presenting most frequently in southeast Asian countries.

Combined Endocardial-Epicardial Versus Endocardial Catheter Ablation Alone for Ventricular Tachycardia in Structural Heart Disease: A Systematic Review and Meta-Analysis.

Objectives: This study sought to determine whether combined endocardial-epicardial (endo-epi) ablation was superior to endocardial only ablation in patients with scar-related ventricular tachycardia (VT).

Background: Limited single-center studies suggest that combined endo-epi ablation strategy may be superior to endocardial ablation (endo) alone in patients with nonischemic cardiomyopathy (NICM) and arrhythmogenic right ventricular cardiomyopathy (ARVC), and ischemic cardiomyopathy (ICM).

Methods: A systematic review of Medline, Cochrane, and Embase databases was performed for studies that reported outcomes comparing endo-epi with endo VT ablation alone.

Thermoplasmatales and sulfur-oxidizing bacteria dominate the microbial community at the surface water of a CO-rich hydrothermal spring located in Tenorio Volcano National Park, Costa Rica.

Here we report the chemical and microbial characterization of the surface water of a CO-rich hydrothermal vent known in Costa Rica as Borbollones, located at Tenorio Volcano National Park. The Borbollones showed a temperature surrounding 60 °C, a pH of 2.4 and the gas released has a composition of ~ 97% CO, ~ 0.

Bivalirudin versus heparin in patients undergoing percutaneous peripheral interventions: A systematic review and meta-analysis.

Background: Bivalirudin may be an effective alternative anticoagulant to heparin for use in percutaneous peripheral interventions. We aimed to compare the safety and efficacy of bivalirudin versus heparin as the procedural anticoagulant agent in patients undergoing percutaneous peripheral intervention.

Methods: For this meta-analysis and systematic review, we conducted a search in PubMed, Medline, Embase, and Cochrane for all the clinical studies in which bivalirudin was compared to heparin as the procedural anticoagulant in percutaneous peripheral interventions.

Is it safe to stop oral anticoagulation after catheter ablation for atrial fibrillation?

Atrial fibrillation is the most common arrhythmia worldwide. Its increasing prevalence has made the use of oral anticoagulants for stroke prevention routine; however, their use after the blanking period of catheter ablation remains uncertain. Areas covered: This review outlines the pros and cons of stopping oral anticoagulation after catheter ablation.