Mechanisms and therapeutic implications of hypermutation in gliomas.

A high tumour mutational burden (hypermutation) is observed in some gliomas1-5; however, the mechanisms by which hypermutation develops and whether it predicts the response to immunotherapy are poorly understood. Here we comprehensively analyse the molecular determinants of mutational burden and signatures in 10,294 gliomas. We delineate two main pathways to hypermutation: a de novo pathway associated with constitutional defects in DNA polymerase and mismatch repair (MMR) genes, and a more common post-treatment pathway, associated with acquired resistance driven by MMR defects in chemotherapy-sensitive gliomas that recur after treatment with the chemotherapy drug temozolomide. Experimentally, the mutational signature of post-treatment hypermutated gliomas was recapitulated by temozolomide-induced damage in cells with MMR deficiency. MMR-deficient gliomas were characterized by a lack of prominent T cell infiltrates, extensive intratumoral heterogeneity, poor patient survival and a low rate of response to PD-1 blockade. Moreover, although bulk analyses did not detect microsatellite instability in MMR-deficient gliomas, single-cell whole-genome sequencing analysis of post-treatment hypermutated glioma cells identified microsatellite mutations. These results show that chemotherapy can drive the acquisition of hypermutated populations without promoting a response to PD-1 blockade and supports the diagnostic use of mutational burden and signatures in cancer.

A review of immunization legislation for children in English- and Dutch-speaking Caribbean countries.

Objective: To assess the legislative frameworks concerning childhood vaccination in the English- and Dutch-speaking Caribbean and propose a model legislative framework for Caribbean countries. Methods: This study included a survey of 22 countries and territories in the Caribbean regarding legal vaccination mandates for school entry, budget allocations, sanctions, or exemptions. A legal consultant conducted a comprehensive search and analysis of legislation regarding vaccination among 13 Caribbean countries/territories. A comparative analysis of the legislation under five themes-legislative structure, mandatory vaccination, national immunization schedule, sanctions, and exemptions-formed the basis for the proposed model legislation. Results: Among the 22 Caribbean countries/territories, 17 (77%) had legislation mandating vaccination, 16 (94%) mandated vaccination for school entry, 8 (47%) had a dedicated budget for immunization programs, and 13 (76%) had no legislated national schedules. The source of legislation includes six (35%) using the Education Act, eight (47%) the Public Health Act, and five (29%) a free-standing Vaccination Act. Three countries/territories-Jamaica, Montserrat, and Saint Lucia-had immunization regulations. In 12 (71%) of the 17 countries with legislation, sanctions were included, and 10 (59%) permitted exemptions for medical or religious/philosophical beliefs. Conclusions: Several countries in the Caribbean have made failure to vaccinate a child an offense. By summarizing the existing legislative frameworks and approaches to immunization in the Caribbean, the analysis guides policymakers in making effective changes to immunization legislation in their own countries.

Achieving global equity for COVID-19 vaccines: Stronger international partnerships and greater advocacy and solidarity are needed.

Peter Figueroa and co-authors advocate for equity in the worldwide provision of COVID-19 vaccines.

Deep-Learning Detection of Cancer Metastases to the Brain on MRI.

BACKGROUND: Approximately one-fourth of all cancer metastases are found in the brain. MRI is the primary technique for detection of brain metastasis, planning of radiotherapy, and the monitoring of treatment response. Progress in tumor treatment now requires detection of new or growing metastases at the small subcentimeter size, when these therapies are most effective. PURPOSE: To develop a deep-learning-based approach for finding brain metastasis on MRI. STUDY TYPE: Retrospective. SEQUENCE: Axial postcontrast 3D T1 -weighted imaging. FIELD STRENGTH: 1.5T and 3T. POPULATION: A total of 361 scans of 121 patients were used to train and test the Faster region-based convolutional neural network (Faster R-CNN): 1565 lesions in 270 scans of 73 patients for training; 488 lesions in 91 scans of 48 patients for testing. From the 48 outputs of Faster R-CNN, 212 lesions in 46 scans of 18 patients were used for training the RUSBoost algorithm (MatLab) and 276 lesions in 45 scans of 30 patients for testing. ASSESSMENT: Two radiologists diagnosed and supervised annotation of metastases on brain MRI as ground truth. This data were used to produce a 2-step pipeline consisting of a Faster R-CNN for detecting abnormal hyperintensity that may represent brain metastasis and a RUSBoost classifier to reduce the number of false-positive foci detected. STATISTICAL TESTS: The performance of the algorithm was evaluated by using sensitivity, false-positive rate, and receiver's operating characteristic (ROC) curves. The detection performance was assessed both per-metastases and per-slice. RESULTS: Testing on held-out brain MRI data demonstrated 96% sensitivity and 20 false-positive metastases per scan. The results showed an 87.1% sensitivity and 0.24 false-positive metastases per slice. The area under the ROC curve was 0.79. CONCLUSION: Our results showed that deep-learning-based computer-aided detection (CAD) had the potential of detecting brain metastases with high sensitivity and reasonable specificity. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2 J. Magn. Reson. Imaging 2020;52:1227-1236.

Predation by Engytatus varians (Distant) (Hemiptera: Miridae) on Bactericera cockerelli (Sulcer) (Hemiptera: Triozidae) and two Spodoptera species.

Predation by Engytatus varians (Distant) adults on different development stages of the prey species Bactericera cockerelli (Sulcer) (egg, second, and third nymphal instars), Spodoptera exigua (Hübner) and Spodoptera frugiperda (J. E. Smith) (egg, first, and second larval instars) was evaluated using tomato (Solanum lycopersicum L.) leaflets or plants. These insects are the primary pest of several agriculturally important crops. The influence of E. varians age on the predation capacity was also analysed. Engytatus varians females consumed significantly more B. cockerelli eggs and nymphs than males. Additionally, female predators consumed significantly more second than third instar prey at two predator ages, while males consumed significantly more the second instar than third instar prey at all predator ages. In most of the cases, females also consumed significantly more S. exigua and S. frugiperda eggs than males; however, in terms of larvae consumption, this difference was observed only in some predator ages. Females consumed more the first than second instar S. exigua than males, whereas this behaviour was only observed in males when the predators were 15 and 17 days old. No significant differences were observed in the consumption of first and second instar of S. frugiperda for both sexes of the predators. Predator age did not cause any systematic effects on the predation rates of any prey species. Based on these results, we confirmed that E. varians has potential as a biological control agent for B. cockerelli and also for the Spodoptera species bioassayed.

The HIV epidemic in Jamaica: a need to strengthen the National HIV Program.

OBJECTIVES: To assess the status of the HIV epidemic and programmatic implementation in Jamaica while identifying strategies for achieving effective HIV control. METHODS: The assessment included a review of the core indicators of the UNAIDS Global Monitoring Framework, a desk review of program reports, and unstructured interviews of stakeholders. RESULTS: HIV prevalence among adults in Jamaica was 1.5% in 2018 with an estimated 32 617 persons living with HIV (PLHIV) and 27 324 persons (83.8%) diagnosed with HIV; 12 711 (39.0% of all PLHIV or 46.5% aware of their status) were on anti-retroviral therapy (ART) in the public health sector and 61.8% PLHIV on ART were virally suppressed. HIV prevalence among men who have sex with men remains high (31.4% in 2011, 29.6% in 2017) but has declined among female sex workers (12% in 1990, 2% in 2017). HIV prevalence among public sexually transmitted infection clinic attendees, prison inmates and the homeless has increased in recent years. During 2018 approximately 200 000 persons (14% of the population 15-49 years) were tested with 1 165 newly diagnosed PLHIV, indicating that many of the estimated 1 600 newly infected persons in 2018 were unaware of their status. CONCLUSIONS: Critical policy initiatives are needed to reduce barriers to HIV services, ensure young persons have access to condoms and contraceptives, affirm the rights of the marginalized, reduce stigma and discrimination, and introduce pre-exposure prophylaxis. While HIV spread in Jamaica has slowed, the UNAIDS Fast Track goals are lagging. The HIV program must be strengthened to effectively control the epidemic.

Cause of death among HIV patients in London in 2016.

OBJECTIVES: Since 2013, the London HIV Mortality Review Group has conducted annual reviews of deaths among people with HIV to reduce avoidable mortality. METHODS: All London HIV care Trusts reported data on 2016 patient deaths in 2017. Deaths were submitted using a modified Causes of Death in HIV reporting form and categorized by a specialist HIV pathologist and two HIV clinicians. RESULTS: There were 206 deaths reported; 77% were among men. Median age at death was 56 years. Cause was established for 82% of deaths, with non-AIDS-related malignancies and AIDS-defining illnesses being the most common causes reported. Risk factors in the year before death included: tobacco smoking (37%), excessive alcohol consumption (19%), non-injecting drug use (10%), injecting drug use (7%) and opioid substitution therapy (6%). Thirty-nine per cent of patients had a history of depression, 33% chronic hypertension, 27% dyslipidaemia, 17% coinfection with hepatitis B virus and/or hepatitis C virus and 14% diabetes mellitus. At the time of death, 81% of patients were on antiretroviral therapy (ART), 61% had a CD4 count < 350 cells/µL, and 24% had a viral load ≥ 200 HIV-1 RNA copies/mL. Thirty-six per cent of deaths were unexpected; 61% of expected deaths were in hospital. Two-thirds of expected deaths had a prior end-of-life care discussion documented. CONCLUSIONS: In 2016, most deaths were attributable to non-AIDS-related conditions and the majority of patients were on ART and virally suppressed. However, several potentially preventable deaths were identified and underlying risk factors were common. As London HIV patients are not representative of people with HIV in the UK, a national mortality review is warranted.

HIV care cost in England: a cross-sectional analysis of antiretroviral treatment and the impact of generic introduction.

OBJECTIVES: Reliable and timely HIV care cost estimates are important for policy option appraisals of HIV treatment and prevention strategies. As HIV clinical management and outcomes have changed, we aimed to update profiles of antiretroviral (ARV) usage pattern, patent/market exclusivity details and management costs in adults (≥ 18 years old) accessing HIV specialist care in England. METHODS: The data reported quarterly to the HIV and AIDS Reporting System in England was used to identify ARV usage pattern, and were combined with British National Formulary (BNF) prices, non-ARV care costs and patent/market exclusivity information to generate average survival-adjusted lifetime care costs. The cumulative budget impact from 2018 to the year in which all current ARVs were expected to lose market exclusivity was calculated for a hypothetical 85 000 (± 5000) person cohort, which provided an illustration of potential financial savings afforded by bioequivalent generic switches. Price scenarios explored BNF70 (September 2015) prices and generics at 10/20/30/50% of proprietary prices. The analyses took National Health Service (NHS) England's perspective (as the payer), and results are presented in 2016/2017 British pounds. RESULTS: By 2033, most currently available ARVs would lose market exclusivity; that is, generics could be available. Average per person lifetime HIV cost was ~£200 000 (3.5% annual discount) or ~£400 000 (undiscounted), reducing to ~£70 000 (3.5% annual discount; ~£120 000 undiscounted) with the use of generics (assuming that generics cost 10% of proprietary prices). The cumulative budget to cover 85 000 (± 5000) persons for 16 years (2018-2033) was £10.5 (± 0.6) billion, reducing to £3.6 (± 0.2) billion with the use of generics. CONCLUSIONS: HIV management costs are high but financial efficiency could be improved by optimizing generic use for treatment and prevention to mitigate the high cost of lifelong HIV treatment. Earlier implementation of generics as they become available offers the potential to maximize the scale of the financial savings.

High prevalence of psychiatric and substance use disorders among persons seeking treatment for HIV and other STIs in Jamaica: a short report.

This cross-sectional study explored the range of psychiatric and substance use disorders and unmet need for mental health care among 84 HIV-positive and 44 HIV-negative public clinic attendees in Jamaica. We used a brief interviewer-administered diagnostic tool, the Client Diagnostic Questionnaire. Two-thirds (65.6%) screened positive for at least one psychiatric disorder; 30.5% screened positive for multiple disorders. The most common disorders were post-traumatic stress disorder (PTSD) (41.4%), alcohol abuse (22.7%), and depressive disorders (21.9%). One in fourteen (7.1%) participants with at least one diagnosis received care in the last 6 months. Adjusting for age and sex, PTSD was associated with non-adherence to antiretroviral treatment (AOR = 5.32), anxiety disorders (AOR = 5.82), depression (AOR = 4.29), and suicidal ideation (AOR = 8.17). Psychiatric and substance use disorders, particularly PTSD, were common among STI/HIV clinic attendees in Jamaica. Such clinics may be efficient places to screen, identify, and treat patients with psychiatric disorders in low- and middle- income countries.

A peptide derived from enzymatic digestion of globulins from amaranth shows strong affinity binding to the replication origin of Tomato yellow leaf curl virus reducing viral replication in Nicotiana benthamiana.

Tomato yellow leaf curl virus (TYLCV; genus Begomovirus; family Geminiviridae) infects mainly plants of the family Solanaceae, and the infection induces curling and chlorosis of leaves, dwarfing of the whole plant, and reduced fruit production. Alternatives for direct control of TYLCV and other geminiviruses have been reported, for example, the use of esterified whey proteins, peptide aptamer libraries or artificial zinc finger proteins. The two latter alternatives affect directly the replication of TYLCV as well as of other geminiviruses because the replication structures and sequences are highly conserved within this virus family. Because peptides and proteins offer a potential solution for virus replication control, in this study we show the isolation, biochemical characterization and antiviral activity of a peptide derived from globulins of amaranth seeds (Amaranthus hypochondriacus) that binds to the replication origin sequence (OriRep) of TYLCV and affects viral replication with a consequent reduction of disease symptoms in Nicotiana benthamiana. Aromatic peptides obtained from papain digests of extracted globulins and albumins of amaranth were tested by intrinsic fluorescent titration and localized surface resonance plasmon to analyze their binding affinity to OriRep of TYLCV. The peptide AmPep1 (molecular weight 2.076 KDa) showed the highest affinity value (Kd = 1.8 nM) for OriRep. This peptide shares a high amino acid similarity with a part of an amaranth 11S globulin, and the strong affinity of AmPep1 could be explained by the presence of tryptophan and lysine facilitating interaction with the secondary structure of OriRep. In order to evaluate the effect of the peptide on in vitro DNA synthesis, rolling circle amplification (RCA) was performed using as template DNA from plants infected with TYLCV or another begomovirus, pepper huasteco yellow vein virus (PHYVV), and adding AmPep1 peptide at different concentrations. The results showed a decrease in DNA synthesis of both viruses at increasing concentrations of AmPep1. To further confirm the antiviral activity of the peptide in vivo, AmPep1 was infiltrated into leaves of N. benthamiana plants previously infected with TYLCV. Plants treated with AmPep1 showed a significant decrease in virus titer compared with untreated N. benthamiana plants as well as reduced symptom progression due to the effect of AmPep1 curtailing TYLCV replication in the plant. The peptide also showed antiviral activity in plants infected with PHYVV. This is the first report, in which a peptide is directly used for DNA virus control in plants, supplied as exogenous application and without generation of transgenic lines.

Brain MRS glutamine as a biomarker to guide therapy of hyperammonemic coma.

Acute idiopathic hyperammonemia in an adult patient is a life-threatening condition often resulting in a rapid progression to irreversible cerebral edema and death. While ammonia-scavenging therapies lower blood ammonia levels, in comparison, clearance of waste nitrogen from the brain may be delayed. Therefore, we used magnetic resonance spectroscopy (MRS) to monitor cerebral glutamine levels, the major reservoir of ammonia, in a gastric bypass patient with hyperammonemic coma undergoing therapy with N-carbamoyl glutamate and the ammonia-scavenging agents, sodium phenylacetate and sodium benzoate. Improvement in mental status mirrored brain glutamine levels, as coma persisted for 48h after plasma ammonia normalized. We hypothesize that the slower clearance for brain glutamine levels accounts for the delay in improvement following initiation of treatment in cases of chronic hyperammonemia. We propose MRS to monitor brain glutamine as a noninvasive approach to be utilized for diagnostic and therapeutic monitoring purposes in adult patients presenting with idiopathic hyperammonemia.

Identification of genomic islands in Chilean Piscirickettsia salmonis strains and analysis of gene expression involved in virulence.

Piscirickettsia salmonis, an agent of Piscirickettsiosis, is the cause of major losses in the Chilean salmon industry. We identified, characterized and bioinformatically analysed genomic islands in field strains of P. Salmonis, using the bioinformatic software PIPS, that uses the characteristics of the islands of pathogenicity to identify them. We analysed nine partially sequenced genomes in different new field strains, and compared them with the LF-89 (Type strain) genome, selecting a genomic island present in all of them. We then evaluated the relative expression of three genes present in that island. From the obtained results, we conclude that the expression of the tcf gene is directly proportional to the cytopathogenicity in vitro of the bacteria; the product of the dnsa gene could contribute to its pathogenicity, but would be potentiated by one or more factors. The product of the gene liso is necessary for the virulence process and could have functions in early stages of infection. Regarding the strains, the IBM-040 strain showed a significant increase in the expression of all the genes in the study. Contrarily, LF-89 only presented a significant increase in expression of the gene liso, which correlates with the cytopathogenicity in vitro observed in the SHK-1 cells.

Search and analysis of genes involved in antibiotic resistance in Chilean strains of Piscirickettsia salmonis.

Piscirickettsia salmonis is the pathogen causing Piscirickettsiosis. For treatment, the industry mainly uses oxytetracycline and florfenicol, so it is essential to understand the degree of susceptibility of this pathogen to these drugs. But this is still unknown for a large number of P. salmonis strains, as are the molecular mechanisms responsible for greater or lesser susceptibility. However, genes that confer resistance to these antimicrobials have been reported and characterized for this and other bacterial species, among which are membrane proteins that take out the drug. Our results identified differences in the degree of susceptibility to both antibiotics among different Chilean isolated of these bacteria. We analysed 10 available genomes in our laboratory and identified ~140 genes likely to be involved in antibiotic resistance. We analysed six specific genes, which suggests that some of them would eventually be relevant in conferring resistance to both antibiotics, as they encode for specific transporter proteins, which increase the number of transcripts when grown in media with these antibiotics. Our results were corroborated with EtBr permeability analysis, which revealed that the LF-89 strain accumulates this compound and has a reduced capacity to expulse it compared with the field strains.

The Expanded Program on Immunization in the English- and Dutch-speaking Caribbean (1977-2016): reasons for its success.

The year 2017 marks the 40th year of the establishment of the Expanded Program on Immunization (EPI) by the Pan American Health Organization (PAHO), the regional office of the World Health Organization (WHO) in the Americas, the first WHO region certified as eliminating poliomyelitis (1994), measles (2016), and rubella and congenital rubella syndrome (CRS) (2015). The English- and Dutch-speaking Caribbean subregion of the Americas paved the way in eliminating these diseases. This report highlights the innovative strategies used in this subregion that helped make the EPI a success. A review of published/unpublished reports and written and oral accounts of the experiences of Immunization Advisors and national EPI managers was conducted to identify the strategies used to strengthen the Immunization program in the subregion since its implementation by countries in 1977. The results show that these include strong collective political commitment, country-specific immunization legislation, joint use of a standard coverage monitoring chart, annual meetings of national EPI managers, collaborative development of annual national Plans of Action for Immunization, coordinated implementation of vaccination campaigns, subregional oversight of surveillance and laboratory support, a performance award system for countries, and subregional standardized templates for immunization manuals and procedural guidelines. Political will and support for immunization has been particularly strong in this subregion, where 99% of EPI costs are borne by governments. Dedicated health staff and multi-country agreement and application of strategies have led to high sustained coverage and good-quality surveillance, resulting in the absence of wild polio for 34 years, measles for 25 years, CRS for 17 years, and rubella for 15 years.

En el 2017 se celebra el cuadragésimo año de la instauración del Programa Ampliado de Inmunización (PAI) por la Organización Panamericana de la Salud (OPS), la Oficina Regional de la Organización Mundial de la Salud (OMS) para las Américas. Esta fue la primera región de la OMS que obtuvo la certificación de la eliminación de la poliomielitis (1994), el sarampión (2016) y la rubéola y el síndrome de rubéola congénita (2015). La subregión de habla inglesa y holandesa del Caribe en las Américas abrió el camino a la eliminación de estas enfermedades. En el presente artículo se destacan las estrategias innovadoras utilizadas en esta subregión que contribuyeron al éxito del PAI.Se llevó a cabo una revisión de los informes publicados e inéditos y de los relatos escritos y orales de las experiencias de los Expertos en Inmunización y los gerentes nacionales del PAI con el objeto de determinar las estrategias utilizadas con miras a fortalecer el programa de vacunación en la subregión, desde su introducción en los países en 1977. Los resultados ponen de manifiesto que los programas comportaban un fuerte compromiso político colectivo, legislaciones en materia de inmunización propias de cada país, la utilización común de un registro gráfico normalizado de monitoreo de coberturas de vacunación, reuniones anuales de los gerentes nacionales del PAI, la elaboración conjunta de planes de acción anuales nacionales sobre vacunas, la ejecución coordinada de campañas de vacunación, la supervisión de la vigilancia y el apoyo a los laboratorios a escala subregional, un sistema de reconocimiento al desempeño de los países y plantillas subregionales normalizadas de los manuales de vacunación y los procedimientos recomendados. La voluntad política y el apoyo a la vacunación han sido muy sólidos en esta subregión, donde los gobiernos sufragan 99% de los costos del PAI. La existencia de personal sanitario dedicado y los acuerdos multinacionales y la aplicación de las estrategias permitieron alcanzar una alta cobertura de manera sostenida y una vigilancia de buena calidad, cuyo resultado fue la ausencia de poliomielitis salvaje durante 34 años, de sarampión durante 25 años, del síndrome de la rubéola congénita durante 17 años y de la rubéola durante 15 años.

O ano de 2017 marca o 40º aniversário da criação do Programa Ampliado de Imunização (PAI) pela Organização Pan-Americana da Saúde (OPAS), Escritório Regional da Organização Mundial da Saúde (OMS) nas Américas, primeira Região da OMS certificada como tendo eliminado a poliomielite (1994), o sarampo (2016) e a rubéola e síndrome da rubéola congênita (2015). A sub-região das Américas constituída pelos países do Caribe de língua inglesa e holandesa abriu caminho ao eliminar essas doenças. Este relato destaca as estratégias inovadoras usadas nesta sub-região que contribuíram para tornar o PAI um programa bem-sucedido.Foi realizada uma análise de informes publicados/inéditos e relatos orais e escritos da experiência dos assessores para assuntos de imunização e coordenadores nacionais do PAI visando identificar as estratégias aplicadas para consolidar o programa nos países da sub-região desde a sua implementação em 1977. Os resultados demonstram firme compromisso político coletivo, legislação de vacinação própria em cada país, uso conjunto de uma lista padrão para o monitoramento da cobertura, reuniões anuais dos coordenadores nacionais do PAI, desenvolvimento colaborativo de planos de ação nacionais anuais para vacinação, campanhas coordenadas de vacinação, supervisão sub-regional da vigilância e infraestrutura laboratorial, sistema de premiação dos países por bom desempenho, modelos padronizados para os manuais de vacinação e protocolos de procedimentos. A sub-região se caracteriza sobretudo pela vontade e apoio políticos para vacinação, sendo 99% do custo do PAI financiados pelos governos. Equipes de saúde diligentes, acordos entre vários países e emprego de estratégias são fatores que contribuem para elevada cobertura sustentada e vigilância de boa qualidade com a consequente não ocorrência de casos de poliomielite por vírus selvagem por 34 anos, de casos de sarampo por 25 anos, de casos de síndrome da rubéola congênita por 17 anos e de casos de rubéola por 15 anos.

[Functional endoscopic evaluation of swallowing in infants with deglutition disorders]. / Evaluación funcional endoscópica de la deglución en lactantes con alteración en la mecánica de la deglución.

BACKGROUND: Functional endoscopic evaluation of swallowing (FEES) is a recognized method for Deglutition Disorders (DD) in adults, with anecdotal experience in children, obtaining not conclusive results. OBJECTIVE: To compare the accuracy of test FEES in infants with high suspicion of altered DD seen in a third level hospital with the gold standard Videofluoroscopic (VF). PATIENTS, MATERIAL AND METHODS: The results and findings by FEES and VF of 66 children with clinical diagnosis of DD were compared. STATISTICAL ANALYSIS: An estimate of the sensitivity and specificity of FEES was performed. As well as calculating positive predictive value (PPV), negative predictive value (NPV) and likelihood ratios. RESULTS: 60 patients enrolled, 4 and FEES showed high sensitivity to identify the presence of aspiration and penetration (9 98%) and high specificity for the arrest of spillage and waste (94% and 95%). Gastroesophageal reflux to make the diagnosis of DD with FEES had a sensitivity of 80% and specificity of 84%. Spill and penetration had the highest agreement with respect to the gold standard of 0.81. CONCLUSIONS: FEES in infants diagnosed with DD had a sensitivity of 80.8% and specificity 85.3%. 0696 concordance regarding to the VFD in the diagnosis of DD, and to identify suction stroke had a kappa of 0815.

ANTECEDENTES: La Evaluación Funcional Endoscópica de la deglución (EFED) es un método reconocido para evaluar alteración en la mecánica de la deglución (AMD), con experiencia anecdótica en niños, y con resultados no concluyentes. OBJETIVO: Comparar la exactitud de la EFED en lactantes con alta sospecha de alteración en la mecánica de la deglución atendidos en un hospital de tercer nivel, con el estándar de oro, la Vídeo Fluoroscopia de Deglución (VFD). Tipo de estudio: transversal, analítico, observacional, ambilectivo. Diseño: Prueba diagnóstica. PACIENTES, MATERIAL Y METODOS: Se compararon los resultados y hallazgos por EFED y VFD de 66 niños con diagnóstico clínico de AMD. ANALISIS ESTADISTICO: Se realizó la estimación de sensibilidad y especificidad de la EFED, así como cálculo de valor predictivo positivo (VPP), valor predictivo negativo (VPN) y razones de verosimilitud. RESULTADOS: De los 60 pacientes incluidos, el EFED presentó una alta sensibilidad para la presencia de aspiración y penetración (94 y 98%), y una alta especificidad para la detención de derrame y residuo (94% y 95%). El reflujo gastroesofágico para hacer el diagnóstico de AMD con el EFED tuvo una sensibilidad del 80% y especificidad del 84%. Derrame y penetración tuvieron la más alta concordancia con respecto al estándar de oro de 0.81. CONCLUSIONES: La EFED tuvo una sensibilidad del 80,8% y especificidad 85,3% en lactantes con diagnóstico de AMD. Una concordancia del 0,696 con respecto a la VFD en el diagnóstico de la AMD, y para identificar derrame y aspiración tuvo una kappa de 0,815.

Freshwater ecosystems and aquatic insects: a paradox in biological invasions.

Biological invasions have increased significantly in response to global change and constitute one of the major causes of biodiversity loss. Insects make up a large fraction of invasive species, in general, and freshwaters are among the most invaded ecosystems on our planet. However, even though aquatic insects dominate most inland waters, have unparalleled taxonomic diversity and occupy nearly all trophic niches, there are almost no invasive insects in freshwaters. We present some hypotheses regarding why aquatic insects are not common among aquatic invasive organisms, suggesting that it may be the result of a suite of biological, ecological and anthropogenic factors. Such specific knowledge introduces a paradox in the current scientific discussion on invasive species; therefore, a more in-depth understanding could be an invaluable aid to disentangling how and why biological invasions occur.