Multiple stressor responses are regulated by sirtuins in Mytilus congeners.

Understanding physiological tolerances of marine organisms to environmental stress is key to predicting species susceptability under climate change. Along the Pacific Coast of the U.S.A. intertidal mussel congeners (genus Mytilis) vary in their physiological stress tolerances, with the invasive M. galloprovincialis being heat tolerant but vulnerable to hyposalinity while the native M. trossulus is vulnerable to heat stress and tolerant of hyposalinity. Sirtuins, a family of NAD+-dependent deacylases, may influence the environmental stressor tolerances in these mussel congeners. The purpose of our study was to determine the mechanism by which sirtuins may confer differential stress responses in the two mussel congeners. Mussels (N = 6 per species) were acclimated to laboratory conditions in tidal simulators and exposed to sirtuin inhibitors (suramin and nicotinamide). Following inhibition, mussels were exposed to hyposalinity stress (29 ppt) for 6 h followed by aerial heat stress (32 °C) for 6 h after which mussel gill was dissected for proteomic analysis. During sirtuin inhibition we found a reduction of cellular stress response (CSR) proteins (molecular chaperones, antioxidants), which are key to maintaining cellular homeostasis. Moreover, we found differential stress responses between the two species under aerial heat combined with hyposalinity exposure. Three-way interactions (aerial heat, hyposalinity and sirtuin inhibition combined) showed complex interactive effects with sirtuins as potential modulators. Thus, our study suggests that sirtuins are contributing to the species-specific CSR in Mytilus and our multiple-stressor approach provides information used to make predictions regarding climate change effects on these competing species.

Sirtuins as regulators of the cellular stress response and metabolism in marine ectotherms.

The effects of climate change are altering the environmental landscape of marine habitats and exposing organisms to stressful conditions that may exceed their tolerance limits. Marine intertidal organisms are well adapted to fluctuating environments by adjusting energy metabolism and inducing the cellular stress response (CSR). Recent studies have shown that food availability can influence stress tolerance of marine ectotherms where a well-fed organism is more "robust" and more likely to survive a stressor than an animal under a low-food regime. We propose that the link between food availability and stress tolerance in marine ectotherms may be regulated by sirtuins, NAD+-dependent deacylases. In model organisms sirtuins act as energy sensors and are active under calorie restricted states where they target and regulate cellular metabolism, minimize oxidative stress, and influence the CSR. However, we know little regarding sirtuins in marine ectotherms. Herein we review the current literature on sirtuins in marine ectotherms including marine teleosts, limpets, and mussels. We show that the role of sirtuins in marine ectotherms is conserved from model organisms in regulating the CSR and energy, but the direct connection to NAD+ status under fed and starved conditions requires more attention. Although there is a beginning foundation of research regarding sirtuins in marine organisms, it is limited and would benefit from targeted studies investigating sirtuin activity in various tissues and animals under multiple stressors, NAD+/NADH levels under various fed states, and by using known sirtuin inhibitors and activators to elucidate the potential targets of sirtuins in marine animals.

[Exercise and physical activity in adults who underwent bariatric surgery. Consensus document]. / Recomendaciones de actividad física y ejercicio en el paciente adulto sometido a cirugía bariátrica. Documento de Consenso.

Physical exercise is useful in people who underwent bariatric surgery. However, the right dosage is still a topic for discussion. The aim of this article is to consolidate the prescription criteria for physical activity and exercise in bariatric patients. A panel of experts to whom the topics were previously assigned for review, met to reach a consensus. Each topic was presented and subjected to discussion and voting by the participants and attendants who were exercise professionals from different obesity treatment centers. We report the conclusions reached for aerobic exercise, strength training, protein supplementation and physical activity for weight maintenance in bariatric patients.

Sirtuins regulate proteomic responses near thermal tolerance limits in the blue mussels Mytilus galloprovincialis and Mytilus trossulus.

The blue mussels Mytilus galloprovincialis and M. trossulus are competing species with biogeographical ranges set in part by environmental exposure to heat and hyposalinity. The underlying cellular mechanisms influencing interspecific differences in stress tolerance are unknown, but are believed to be under regulation by sirtuins, nicotinamide adenine dinucleotide (NAD+)-dependent deacylases that play a critical role in the cellular stress response. A comparison of the proteomic responses of M. galloprovincialis and M. trossulus to an acute heat shock in the presence and absence of the sirtuin inhibitor suramin (SIRT1, 2 and 5) showed that sirtuins affected molecular chaperones, oxidative stress proteins, metabolic enzymes, cytoskeletal and signaling proteins more in the heat-sensitive M. trossulus than in the heat-tolerant M. galloprovincialis Interactions between sirtuin inhibition and changes in the abundance of proteins of ß-oxidation and oxidative stress in M. trossulus suggest a greater role of sirtuins in shifting metabolism to reduce the production of reactive oxygen species near thermal limits. Furthermore, RNA-binding proteins initiating and inhibiting translation were affected by suramin in M. galloprovincialis and M. trossulus, respectively. Western blot analysis showed that the levels of mitochondrial sirtuin 5 (SIRT5) were generally three times higher and increased with acute heat stress in response to sirtuin inhibition in M. trossulus but not in M. galloprovincialis, suggesting a possible feedback response in the former species and a greater reliance on SIRT5 for its stress response. Our findings suggest that SIRT5 plays an important role in setting interspecific differences in stress tolerance in Mytilus by affecting the stress proteome.

Multiple-stressor interactions influence embryo development rate in the American horseshoe crab, Limulus polyphemus.

Fertilized eggs of the American horseshoe crab, Limulus polyphemus, are buried in shallow nests above the high tide line, where they are exposed to variations in abiotic conditions during early development. Using a multiple-stressors approach, we examined whether the rate of embryonic development is affected by exposure to combinations of three factors: temperature (25, 30 and 35°C), salinity (5, 15 and 34 ppt) and ambient O2 (5%, 13% and 21% O2). Newly fertilized eggs were incubated under 27 fully factorial stressor combinations for 14 days, then allowed to recover in control conditions (30°C, 34 ppt, 21% O2) for an additional 14 days. Growth rate was measured every 2 days throughout the experiment (N=1289). We found that the effect of isolated stressors (high temperature, low salinity or low O2) reduced developmental success by up to 72% (low salinity), and that stressor combinations showed stronger effects and evidence of complex interactions. For example, low O2 had little effect individually but was lethal in combination with high temperature, and low temperature in isolation slightly decreased the rate of development but reduced the negative effects of low salinity and low O2. Development was delayed under exposure to low O2 but resumed upon return to control conditions after a 10 day lag. These data demonstrate that complex, synergistic interactions among abiotic stressors can substantially alter the development of a coastal invertebrate in ways that may not be predicted from the effects of the stressors in isolation.

Treatment of Truncal Incompetence and Varicose Veins with a Single Administration of a New Polidocanol Endovenous Microfoam Preparation Improves Symptoms and Appearance.

OBJECTIVE: This multicenter, parallel group study was designed to determine if a single administration of ≤15 mL of pharmaceutical-grade polidocanol endovenous microfoam (PEM, now approved in the United States as Varithena [polidocanol injectable foam], BTG International Ltd.) could alleviate symptoms and improve appearance of varicose veins in a typical population of patients with moderate to very severe symptoms of superficial venous incompetence and visible varicosities of the great saphenous vein (GSV) system. METHODS: The primary endpoint was patient-reported venous symptom improvement measured by change from baseline to Week 8 in 7-day average VVSymQ score. Co-secondary endpoints measured improvement in appearance of visible varicose veins from baseline to Week 8, as measured by the Independent Photography Review-Visible Varicose Veins (IPR-V(3)) and Patient Self-assessment of Visible Varicose Veins (PA-V(3)) scores. Patients were randomized to five groups: PEM 0.125% (control), 0.5%, 1%, 2%, or placebo. Adverse events (AEs) were recorded at each study visit. Tertiary endpoints measured duplex ultrasound response, changes in venous clinical severity score, and the modified Venous Insufficiency Epidemiological and Economic Study-Quality of Life/Symptoms. RESULTS: At Week 8, VVSymQ scores for the pooled PEM group (0.5% + 1% + 2%; p < .0001) and individual dose concentrations (p < .001) were significantly superior to placebo. Mean changes from baseline to Week 8 in IPR-V3 and PA-V(3) scores were significantly greater for pooled PEM than for placebo (p < .0001). Most AEs were mild and resolved without sequelae. No pulmonary emboli were reported. CONCLUSIONS: This study demonstrated that a single administration of up to 15 mL of PEM is a safe, effective, and convenient treatment for the symptoms of superficial venous incompetence and the appearance of visible varicosities of the GSV system. Doses of 0.5%, 1%, and 2% PEM appear to have an acceptable risk-benefit ratio.

Rapid cycle deliberate practice improves resident performance during ELBW resuscitation.

BACKGROUND: Neonatal Resuscitation is a required competency for pediatric and family medicine residency programs. Simulation-based training can be used to supplement clinical experience. Rapid Cycle Deliberate Practice (RCDP) has been validated as an effective education model and is gaining favor over traditional simulation models. The aim of this study was to evaluate the effectiveness of a simulation-based rapid cycle deliberate practice (RCDP) intervention on extremely low birth weight (ELBW) infant resuscitation. METHODS: Pediatric and family practice residents were randomized to control and intervention groups and participated in pre- and post-NICU rotation simulations. The intervention group received one RCDP session. Simulations were scored by blinded video review for overall performance, positive pressure ventilation (PPV), endotracheal intubation and behavioral skills. Surveys assessed confidence in ELBW resuscitation. RESULTS: Forty-one residents participated in the study. The RCDP group performed better than the control group at post-rotation evaluation for overall resuscitation performance (65% vs 87%, p = 0.004), administering PPV (63% vs 88%, p = 0.006), and validated behavior skills (1.4 vs 2.0, p = 0.019). Residents in the RCDP group reported greater confidence with ELBW resuscitation. CONCLUSION: An educational intervention using RCDP was associated with improved resident performance and confidence in ELBW resuscitation. RCDP should be considered for NRP and ELBW resuscitation training.

Cost-effectiveness of dapagliflozin plus standard treatment compared to standard therapy for the management of chronic kidney disease in Colombia.

BACKGROUND: The DAPA-CKD study showed that dapagliflozin added to standard treatment reduced the risk of chronic kidney disease progression, and death from renal or cardiovascular causes compared to placebo. OBJECTIVE: Assess the cost-effectiveness of dapagliflozin and standard treatment versus standard treatment alone for chronic kidney disease within the Colombian health system. METHODS: We employed a Markov model based on the DAPA-CKD study, tailored to the Colombian scenario. The model forecasted hospitalizations for heart failure, overall and cardiovascular mortality, and chronic kidney disease progression over a 10-year horizon with a 5% discount rate. RESULTS: Dapagliflozin combined with standard treatment is a cost-effective intervention in treating stage 2-4 CKD. In the base case, the ICER was US $5,366, below 1 GDP (US $6.558) per capita. This was consistent in the sensitivity analyses. CONCLUSION: Our study showed that dapagliflozin, when combined with standard treatment, is cost-effective against standard treatment alone, aligning with Colombia's willingness-to-pay threshold.

Interactive effects of multiple stressors on the physiological performance of the invasive mussel Mytilus galloprovincialis.

The invasive mussel Mytilus galloprovincialis is a heat-tolerant species relative to its competative congener M. trossulus, that dominates warm seawater environments but it is unknown how multiple stressors (MS) may affect its physiology. Our study determined the effects of MS on the metabolic rate (MR), superoxide dismutase (SOD) antioxidant enzyme activity, and clearance rate (CR) of M. galloprovincialis. Mussels were exposed for 7 d to hyposalinity (20, 28, 34 ppt) then to heat shock (17, 20, 25 °C) after which MR and SOD activity were determined. CR was quantified following a 30 min MS exposure. We found a significant influence of MS on MR, SOD, and CR. We identified synergistic effects on MR under the most extreme treatment. SOD activity was the greatest under 20 °C exposure while CR declined under heat shock. Thus, our study suggests that mussels experiencing MS may become energy limited as MR increases and feeding rates decrease.

Comparison of the GMFM-66 and the PEDI Functional Skills Mobility domain in a group of Chinese children with cerebral palsy.

BACKGROUND: Previous research has suggested there is a high level of comparability between the Gross Motor Function Measure-66 (GMFM-66) and the Pediatric Evaluation of Disability Inventory (PEDI) Functional Skills Mobility domain. However, there are only a few studies that have examined the correlations between these instruments. The purpose of this study was to determine the correlation between the GMFM-66 and the PEDI Functional Skills Mobility domain scaled scores in a group of Chinese children with spastic cerebral palsy, at the ages of 12-70 months, in order to explore the feasibility of using them interchangeably. METHODS: Secondary data analysis was conducted of data collected during a prospective international collaborative study that used the GMFM-66 and the PEDI to examine the impact of treatment. This study examined the Pearson correlations between the GMFM-66 and the PEDI Functional Skills Mobility domain at six time points over the course of 28 consecutive weeks for 115 Chinese children who participated at baseline. RESULTS: Pearson correlations between the GMFM-66 and the PEDI Functional Skills Mobility domain ranged from 0.83 to 0.90 for the six time points of data collection, with statistically significant P-values <0.0001 for each correlation. CONCLUSIONS: These results support previous research that the GMFM-66 and the PEDI Functional Skills Mobility domain are complementary assessments that may be used interchangeably when it is not possible to administer both.

Electrospun nanofiber scaffolds for the propagation and analysis of breast cancer stem cells in vitro.

Despite advances in cancer treatment, breast cancer remains the second foremost cause of cancer mortality among women, with a high rate of relapse after initial treatment success. A subpopulation of highly malignant cancer cells, known as cancer stem cells (CSCs), is suspected to be linked to metastasis and relapse. Targeting of CSCs may therefore provide a means of addressing cancer-related mortality. However, due to their low population in vivo and a lack of proper culture platform for their propagation, much of the CSC biology remains unknown. Since maintenance of CSCs is heavily influenced by the tumor microenvironment, this study developed a 3D culture platform that mimics the metastatic tumor extracellular matrix (ECM) to effectively increase CSC population in vitro and allow CSC analysis. Through electrospinning, nanofibers that were aligned, porous, and collagen-coated were fabricated from polycaprolactone to recreate the metastatic tumor ECM assemblage. Breast cancer cells seeded onto the nanofiber scaffolds exhibited gross morphology and cytoskeletal phenotype similar to invasive cancer cells. Moreover, the population of breast cancer stem cells increased in nanofiber scaffolds. Analysis of breast cancer cells grown on the nanofiber scaffolds demonstrated an upregulation of mesenchymal markers and an increase in cell invasiveness suggesting the cells have undergone epithelial-mesenchymal transition. These results indicate that the fabricated nanofiber scaffolds effectively mimicked the tumor microenvironment that maintains the cancer stem cell population, offering a platform to enrich and analyze CSCs in vitro.

Expanding ecological assessment by integrating microorganisms into routine freshwater biomonitoring.

Bioindication has become an indispensable part of water quality monitoring in most countries of the world, with the presence and abundance of bioindicator taxa, mostly multicellular eukaryotes, used for biotic indices. In contrast, microbes (bacteria, archaea and protists) are seldom used as bioindicators in routine assessments, although they have been recognized for their importance in environmental processes. Recently, the use of molecular methods has revealed unexpected diversity within known functional groups and novel metabolic pathways that are particularly important in energy and nutrient cycling. In various habitats, microbial communities respond to eutrophication, metals, and natural or anthropogenic organic pollutants through changes in diversity and function. In this review, we evaluated the common trends in these changes, documenting that they have value as bioindicators and can be used not only for monitoring but also for improving our understanding of the major processes in lotic and lentic environments. Current knowledge provides a solid foundation for exploiting microbial taxa, community structures and diversity, as well as functional genes, in novel monitoring programs. These microbial community measures can also be combined into biotic indices, improving the resolution of individual bioindicators. Here, we assess particular molecular approaches complemented by advanced bioinformatic analysis, as these are the most promising with respect to detailed bioindication value. We conclude that microbial community dynamics are a missing link important for our understanding of rapid changes in the structure and function of aquatic ecosystems, and should be addressed in the future environmental monitoring of freshwater ecosystems.

Refractory epilepsy associated with anti-ribosomal P antibodies successfully treated with topiramate.

We report the case of a 25-year-old woman who developed temporal lobe epilepsy associated with systemic lupus erythematosus (SLE). Serum and cerebrospinal fluid samples showed high titers of anti-ribosomal P (anti-P) antibodies with negative anti-NMDAR antibodies. She was receiving prednisone and azathioprine, with normalization of SLE serum markers, but without changes in titers of anti-P antibodies. No seizure control was achieved using valproic acid, levetiracetam and lamotrigine. However, she had a selective response to topiramate, an AMPAR blocker, maintained during 6 years of follow-up. We discuss the pathophysiology of this autoimmune epilepsy associated with high titer anti-P antibodies.

[Traumatic spondyloptosis C7-T1 without neurologic deficit]. / Espondiloptosis traumática C7-T1 sin compromiso neurológico.

Traumatic spondyloptosis is a serious injury usually caused by high-energy trauma; It consists of the anterior or posterior dislocation of 100% or more of the underlying vertebral body, which can become a total injury of the spinal cord, producing a neurological deficit; this type of injury represents stage 4 and 5 of Allen-Ferguson. Clinical case: A 50-year-old man who suffers a car accident, he receive frontal impact when he was a driver, colliding with the retaining wall, referred from another hospital to emergency room, managed with C7 hemicorpectomy, c7-t1 discectomy, spondylodesis with anterior plate (C6-T1), and posterior approach + Fascetectomies of C7-T1, facet joint screws C6 and transpedicular fixation of T1. Discussion: Subaxial cervical spondyloptosis is relatively rare clinical entity, a complete clinical examination is important in diagnosis, taking in considerations the injury mechanism. For treatment we have a multiple options, at this case anterior-posterior (360 degrees) treatment it was the better option for Us; however, must be personalized and consider the early rehabilitation of patient.

La espondiloptosis traumática es una lesión muy rara y grave generalmente causada por traumatismos de alta energía. Consiste en la dislocación anterior o posterior de 100% o más al cuerpo vertebral subyacente, lo que puede generar compresión y lesión total de la médula espinal, produciendo déficit neurológico; este tipo de lesión representa la etapa 4 y 5 de Allen. Caso clínico: Masculino de 50 años quien sufre accidente automovilístico al colisionar contra muro de contención, generándose lesión de tipo hiperextensión-compresión cervicotorácica, manejado con hemicorpectomía C7, discectomía C7-T1, espondilodesis con placa anterior (C6-C7, C7-T1), toma y aplicación de injerto, abordaje posterior + fascetectomías de C7 + fijación transfacetaria C6 y transpedicular de T1. Discusión: Encontramos que la estabilización temprana con pinza de Gardner más el abordaje anterior y posterior brindan adecuados resultados en cuanto a integridad sensitiva y motora del paciente así como una pronta rehabilitación.

Optimization of 2D-PAGE protocols for proteomic analysis of two nonaxenic toxin-producing freshwater cyanobacteria: Cylindrospermopsis raciborskii and Raphidiopsis sp.

AIMS: To optimize a protocol for the extraction and an in-depth analysis of the soluble protein fraction of two nonaxenic toxin-producing cyanobacteria Cylindrospermopsis raciborskii (hepatotoxin-producing), and Raphidiopsis sp. (neurotoxin-producing), using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). METHODS AND RESULTS: The soluble protein fractions from strains of C. raciborskii and Raphidiosis sp. with different toxicity phenotypes were analysed by 2D-PAGE. Specific protocols were optimized specifically for each strain. Between 500 and 700 sharp protein spots were distinguished in a single 4-7 pH range 2D-PAGE for each cyanobacterium. Comparison of the protein maps of C. raciborskii CS-505 (a cylindrospermopsin-producing strain) and Raphidiopsis sp. D9 (saxitoxin-producing strain) against the nontoxic C. raciborskii strain CS-509 revealed many unique proteins in each protein map. We confirmed that the resolved proteins were cyanobacterial by identifying three randomly chosen protein spots from a Raphidiopsis sp. strain D9 2D-PAGE, using high-performance liquid chromatography (HPLC) tandem mass spectrometry (MS). CONCLUSIONS: The 2D-PAGE conditions presented here provide a robust protocol for proteomic studies in two CYN- and STX-producing model organisms, C. raciborskii and Raphidiopsis sp. SIGNIFICANCE AND IMPACT OF THE STUDY: We present the first protocols for proteomic analyses of Cylindrospermopsis raciborskii and Raphidiopsis sp.

Proteomic changes across a natural temperature gradient in a marine gastropod.

Responses of marine ectotherms to variable environmental temperature often entails maintanence of cellular homeostasis and physiological function through temperature compensation and physiological changes. We investigated the physiological response to thermal stress by examining proteomic changes in the marine kelp forest gastropod and emerging fisheries species Kellet's whelk (Kelletia kelletii) across a naturally-existing thermal gradient that ranges from a warmer-water site inside the species' native range and extends to the northern, cold-water edge of the range. We hypothesized that abundance of cellular stress response and energy metabolism proteins would increase with decreasing temperature in support of cold-compensation. Our exploratory proteomic analysis of whelk gill tissue (N = 6 whelks) from each of the four California Channel Island sites revealed protein abundance changes related to the cytoskeleton, energy metabolism/oxidative stress, and cell signaling. The changes did not correlate consistently with temperature. Nonetheless, whelks from the coldest island site showed increased abundance of energy metabolism and oxidative stress proteins, possibly suggesting oxidative damage of lipid membranes that is ameliorated by antioxidants and may aid in their cold stress response. Similarly, our exploratory analysis revealed abundances of cell signaling proteins that were higher at the coldest site compared to the warmest site, possibly indicating an importance for cell signaling regulation in relatively cooler environments. This study provides protein targets for future studies related to thermal effects in marine animals and may contribute to understanding the physiological response of marine organisms to future ocean conditions.

A high-sensitivity and low dose energy-dispersive X-ray fluorescence system for identification of gadolium accumulations in planar X-ray fluorescence images.

A new technique, based on in-vivo energy dispersive X-ray fluorescence (EDXRF), has been developed to gadolinium (Gd) concentrations identification in planar X-ray fluorescence (XRF) images. Higher signal-to-noise (SNR) ratios while keeping a low radiation dose were achieved. Experimental validation was performed using tissue equivalent phantoms under two different data acquisition criteria. The first criteria consisted on acquiring the energy spectra from different experimental narrow spectrum beam (FWHM = 2.5 keV) with peak central energy above the L edge energy and determining the spectrum which producing Lowest-Limit-of-Detection (Lowest-LoD) for a specific acquisition time. This also provided the minimum dose expected under the condition of minimum irradiation time. The second criteria consisted on measuring the surface dose required to obtain a specific LoD by different narrow spectrum beam, providing the Lowest-Dose setting. Surface (2D) Gd-doped tissue-equivalent phantoms scanning were performed according to optimized scenarios: Lowest-LoD setting (obtaining to central energy of 10.9 keV) and Lowest-Dose setting (obtaining to central energy 12.9 keV). 625 pixel images were acquired in two different conditions: a pre-defined time (5 s) per pixel was set in the first approach, whereas a pre-defined total surface dose (4 mGy) was set to the second approach. According to the results obtained for the first approach, a 58 times reduction was observed when comparing SNR between the Lowest-LoD and Lowest-Dose settings. On the other hand, for the second approach pre-defining total dose during the whole examination, the best SNR was obtained for the Lowest-Dose configuration exhibiting a 42% of increment respecting to the Lowest-LoD configuration and 47 times higher when compared with the limit case of no optimization.

Inhibiting Human Parainfluenza Virus Infection by Preactivating the Cell Entry Mechanism.

Paramyxoviruses, specifically, the childhood pathogen human parainfluenza virus type 3, are internalized into host cells following fusion between the viral and target cell membranes. The receptor binding protein, hemagglutinin (HA)-neuraminidase (HN), and the fusion protein (F) facilitate viral fusion and entry into the cell through a coordinated process involving HN activation by receptor binding, which triggers conformational changes in the F protein to activate it to reach its fusion-competent state. Interfering with this process through premature activation of the F protein has been shown to be an effective antiviral strategy in vitro. Conformational changes in the F protein leading to adoption of the postfusion form of the protein-prior to receptor engagement of HN at the host cell membrane-render the virus noninfectious. We previously identified a small compound (CSC11) that implements this antiviral strategy through an interaction with HN, causing HN to activate F in an untimely process. To assess the functionality of such compounds, it is necessary to verify that the postfusion state of F has been achieved. As demonstrated by Melero and colleagues, soluble forms of the recombinant postfusion pneumovirus F proteins and of their six helix bundle (6HB) motifs can be used to generate postfusion-specific antibodies. We produced novel anti-HPIV3 F conformation-specific antibodies that can be used to assess the functionality of compounds designed to induce F activation. In this study, using systematic chemical modifications of CSC11, we synthesized a more potent derivative of this compound, CM9. Much like CSC11, CM9 causes premature triggering of the F protein through an interaction with HN prior to receptor engagement, thereby preventing fusion and subsequent infection. In addition to validating the potency of CM9 using plaque reduction, fusion inhibition, and binding avidity assays, we confirmed the transition to a postfusion conformation of F in the presence of CM9 using our novel anti-HPIV3 conformation-specific antibodies. We present both CM9 and these newly characterized postfusion antibodies as novel tools to explore and develop antiviral approaches. In turn, these advances in both our molecular toolset and our understanding of HN-F interaction will support development of more-effective antivirals. Combining the findings described here with our recently described physiologically relevant ex vivo system, we have the potential to inform the development of therapeutics to block viral infection.IMPORTANCE Paramyxoviruses, including human parainfluenza virus type 3, are internalized into host cells by fusion between viral and target cell membranes. The receptor binding protein, hemagglutinin-neuraminidase (HN), and the fusion protein (F) facilitate viral fusion and entry into cells through a process involving HN activation by receptor binding, which triggers conformational changes in F to activate it to reach its fusion-competent state. Interfering with this process through premature activation of the F protein may be an effective antiviral strategy in vitro We identified and optimized small compounds that implement this antiviral strategy through an interaction with HN, causing HN to activate F in an untimely fashion. To address that mechanism, we produced novel anti-HPIV3 F conformation-specific antibodies that can be used to assess the functionality of compounds designed to induce F activation. Both the novel antiviral compounds that we present and these newly characterized postfusion antibodies are novel tools for the exploration and development of antiviral approaches.

Prevalence of eosinophilic esophagitis: A multicenter study on a pediatric population evaluated at thirty-six Latin American gastroenterology centers. / Prevalencia de esofagitis eosinofílica: estudio multicéntrico en población pediátrica evaluada en 36 centros de gastroenterología de América Latina.

INTRODUCTION AND OBJECTIVE: Eosinophilic esophagitis is a chronic, immune-mediated disease described in case series and publications worldwide. Over the past twenty years, the authors of different studies have attempted to evaluate its incidence and prevalence. The objetive of the present study was to estimate the prevalence of eosinophilic esophagitis in a group of children seen at 36 pediatric gastroenterology centers in ten Latin American countries. MATERIALS AND METHODS: A multicenter, observational, and cross-sectional study was conducted that estimated the period prevalence of eosinophilic esophagitis in children seen at outpatient consultation and that underwent diagnostic upper gastrointestinal endoscopy for any indication at 36 centers in 10 Latin American countries, within a 3-month time frame. RESULTS: Between April and June 2016, 108 cases of eosinophilic esophagitis were evaluated. Likewise, an average of 29,253 outpatient consultations and 4,152 diagnostic upper gastrointestinal endoscopies were carried out at the 36 participating centers. The period prevalence of eosinophilic esophagitis in the population studied (n=29,253) was 3.69 cases×1,000 (95% CI: 3.04 to 4.44), and among the children that underwent routine upper gastrointestinal endoscopy (n=4,152), it was 26x1,000 (95% CI: 22.6 to 29.4). CONCLUSIONS: The general period prevalence of eosinophilic esophagitis in a group of children evaluated at 36 Latin American pediatric gastroenterology centers was 3.69×1,000, and in the children that underwent endoscopy, it was 26×1,000. There was important prevalence variability between the participating countries and centers. The present analysis is the first study conducted on the prevalence of pediatric eosinophilic esophagitis in Latin America.