Usefulness of clinical scores to improve prediction of significant coronary heart disease after conventional treadmill exercise testing

ANTECEDENTES: en el último consenso de la AHA/ACC se recomiendan puntajes clínicos para mejorar la sensibilidad (68%) y la especificidad (77%) de la prueba de esfuerzo, método diagnóstico de primera línea en el tratamiento de la enfermedad coronaria (una de las principales causas de morbimortalidad en Colombia y el mundo). Sin embargo, son pocas las instituciones del país que los utilizan y son difíciles de aplicar en poblaciones diferentes a aquellas para las cuales fueron desarrollados, haciéndose necesario realizar un estudio que valore su desempeño en nuestro medio. MATERIALES Y MÉTODOS: se escogieron las escalas de Morise y Duke para evaluar por qué han sido validadas en varias poblaciones y fueron citadas en el consenso de la AHA/ACC. Los puntajes de Morise y Duke clasificaron a los pacientes en probabilidad baja, intermedia o alta para enfermedad coronaria. OBJETIVOS PRIMARIOS: validar las escalas de predicción para enfermedad coronaria y determinar el mejor punto de corte para cada escala en un tiempo de seguimiento de un año. OBJETIVOS SECUNDARIOS: determinar un desenlace compuesto por infarto agudo del miocardio, muerte cardiaca, angina que requiere hospitalización, obstrucción coronaria mayor a 50% y/o angioplastia e implante de stent. Determinar el mejor punto de corte mediante curvas de ROC. CRITERIOS DE INCLUSIÓN: pacientes mayores de 18 años de edad, con sospecha de enfermedad coronaria. CRITERIOS DE EXCLUSIÓN: pacientes embarazadas, con enfermedad coronaria documentada, electrocardiograma no interpretable, incapacidad o contraindicación para realizar prueba de esfuerzo por cualquier motivo, depresión del segmento ST menor a 1 mm en el electrocardiograma de base, imposibilidad de realizar seguimiento, y datos incompletos que impidieran el cálculo de las escalas. ANÁLISIS ESTADÍSTICO: la muestra se calculó utilizando error alfa menor de 0,05, error beta menor de 0,20 (poder de 80%), probabilidad de clasificación correcta 0,4, nivel de kappa para la hipótesis nula 0,85 y nivel de kappa para la hipótesis alterna 0,7. Se utilizó el programa Tamaño de la Muestra (TaMaMu), versión 1,0, se requirieron 101 pacientes. RESULTADOS: se reclutaron 127 pacientes y se excluyeron 9; 2 por pruebas de esfuerzo submáximas y 7 por no ser posible el seguimiento, y se analizaron 118. El seguimiento promedio fue de 343 días (1- 564. Edad media: 59 años (29-83). Mujeres: 53% (63) y hombres: 47% (55). Edad media de 59 y de 57 años, respectivamente. Otras características: tabaquismo: 47% (55), dislipidemia: 68% (80), índice de masa corporal mayor a 27,5: 18% (45) y diabetes mellitus: 16% (19). La escala de Morise clasificó 36% (43) en bajo riesgo, 52% (61) en riesgo intermedio y 12% (14) en riesgo alto. Según Duke los resultados fueron 53% (63), 41% (48) y 6% (7) respectivamente. Al interpretar la prueba de esfuerzo aislada, los cardiólogos clasificaron a los pacientes así: 81% (95) negativas, 8% (10) sugestivas y 11% (14) positivas. El punto o desenlace final compuesto se presentó en 11% (14 pacientes). Al comparar a los pacientes con desenlace y sin éste, los primeros se clasificaban con más frecuencia como de alta probabilidad que aquellos que no, con diferencias estadísticamente significativas (Morise: p=0,0002 y Duke: 0,0005). En la escala de Morise con punto de corte de 48, se logró sensibilidad de 92% y especificidad de 68%. En Duke, con punto de corte de 38, fue de 100% y 31%. DISCUSIÓN: la concordancia para Morise es mejor que para los demás métodos evaluados. Adicionar los puntajes clínicos a la interpretación de la prueba de esfuerzo mejora las características operativas de la misma sin aumentar los costos, y se logra un ahorro de 10% a 18%. CONCLUSIONES: los puntajes clínicos aumentan la sensibilidad y la especificidad, por lo cual se deberían utilizar de manera rutinaria para el informe de una prueba de esfuerzo convencional. Sin embargo, se hace necesario buscar soluciones que mejoren aún más dicho desempeño.Q4Artículo original207-214BACKGROUND: in the last AHA/ACC expert consensus document, clinical scores to improve sensitivity (68%) and specificity (77% of the exercise testing, diagnostic method considered a first line diagnostic method for coronary heart disease treatment (one of the main causes of mortality in Colombia and worldwide), are recommended. Nevertheless, few institutions in our country use them and they are difficult to apply in populations different to the ones for which they were developed. For this reason, a study to assess its performance in our environment, is needed MATERIALS AND METHODS: Morise and Duke treadmill scores were chosen to assess the reason for its validation in several populations, and were mentioned in the AHA/ACC consensus. The Morise and Duke scores classified patients in at low, middle and high risk for coronary heart disease. PRIMARY OBJECTIVES: validate the prediction scales for coronary heart disease and determine the best cutoff value for each score in a one year follow-up. SECONDARY OBJECTIVES: determine the composite endpoint for acute myocardial infarction, cardiac death, angina requiring hospitalization, coronary obstruction >50% and/or angioplasty and stent implantation. Determine the best cutoff point through the ROC curves. INCLUSION CRITERIA: patients >18 years old with suspected coronary heart disease. EXCLUSION CRITERIA: pregnant women with documented coronary heart disease, uninterpretable EKG, incapacity or contraindication for performing exercise stress test for any reason, ST depression < 1 mm in basal EKG, follow-up impossibility and incomplete data that might hinder the score calculation. STATISTICAL ANALYSIS: the sample was calculated using alpha error < 0.05, beta error < 0.20 (power 80%), correct classification probability 0.4, kappa level for null hypothesis 0.85 and kappa level for alternate hypothesis 0,7. The Sample Size Program version 1.0 was used. 101 patients were required. RESULTS: 127 patients were enrolled and 9 were excluded: 2 because of submaximal exercise testings and 7 because the follow up was impossible. 118 patients were analyzed. Mean follow-up was 343 days (1 - 564). Mean age was 59 years (29 - 83). Women: 53% (63) and men: 47% (55). Mean age 59 and 57 years respectively. Other characteristics: cigarette smoking: 47% (55), dyslipidemia: 68% (80), body mass index > 27,5: 18% (45) and diabetes mellitus: 16% (19). Morise score classified 36% (43) patients at low risk, 52% (61) at intermediate risk and 12% (14) at high risk. According to Duke the results were 53% (63), 41% (48) and 6% (7) respectively. When interpreting an isolated exercise testing, cardiologists classified patients: 81% (95) negative, 8% (10) suggestive and 11% (14) positive. The composite endpoint appeared in 11% (14 patients). When comparing patients with and without outcomes, the first ones classified more frequently as having higher probability than those that had not, with statistically significant differences (Morise: p = 0,0002 and Duke: 0,0005). In the Morise score with cutoff value 48, 92% sensitivity and 68% specificity was achieved. In Duke, with cutoff value 38, it was 100% and 31% respectively. DISCUSSION: concordance for Morise is better than for the other evaluated methods. The addition of clinical scores to the exercise testing interpretation improves its operative characteristics without any cost increment, achieving savings of 10% to 18%. CONCLUSIONS: clinical scores increase sensitivity and specificity, and for this reason they should be used as routine in the conventional exercise testing report. Nevertheless, it is necessary to look for solutions to improve its performance even further

Tuberculin skin test conversion and association with occupation and demographic characteristics in workers at San Ignacio University Hospital

Objetivos Establecer la prevalencia de positividad, la tasa de conversión de la tuberculina en trabajadores de nuestro hospital y describir las características demográficas y laborales asociadas a esto. Materiales y Métodos Estudio observacional descriptivo en una cohorte de trabajadores del hospital a los que se les realizó la prueba de tuberculina. Se definió la positividad de la prueba de tuberculina como un resultado mayor o igual a 10 mm y la conversión como un aumento de 6 o 10 mm con respecto a la prueba inicial. Resultados Se encontró una prevalencia de 23,7 % y una incidencia de conversión de 13,6 % para el punto de corte mayor de 10 mm y 23 % para el punto de corte de 6 mm. La edad de los sujetos estuvo relacionada a conversión, mientras que no se encontró relación con la ocupación. Conclusión La probabilidad de transmisión de la tuberculosis en trabajadores del hospital es mayor al de la población general. Deben ser implementadas medidas de promoción y prevención para disminuir la transmisión e incrementar el conocimiento de la tuberculosis asociada al cuidado de la salud en los trabajadores.Q3443-449Hospital Universitario San IgnacioObjectives To establish the prevalence of positivity and conversion rate of the tuberculin skin test in workers of our hospital, and to describe the related demographic and occupational characteristics. Materials and Methods An observational, descriptive study was conducted in a cohort of hospital workers who underwent the tuberculin skin test. The positivity of the test was defined as a result of greater than or equal to 10 mm, and conversion was defined as an increase of 6 or 10 mm with respect to the initial test. Results Prevalence of 23.7 % and incidence of conversion of 13.6 % for the major cut-off point of 10 mm, and 23 % for the lesser cut-off point of 6 mm, was found. The age of the subjects was related to the conversion, but there was no relation with occupation. Conclusions The probability of tuberculosis transmission in health-care workers is higher than in the general population. Promotion and prevention measures must be implemented to decrease the transmission and to increase awareness of tuberculosis related to occupational activities

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

Effect of Zn Nanoparticles Doping on Oxytetracycline Removal by Natural Aluminosilicate and Carbon Nanotubes

The presence of antibiotics such as oxytetracycline (OTC) in water and wastewater is considered an environmental problem and, consequently, their elimination is an important topic. The present research shows the removal of OTC from aqueous medium using a quartz-based natural aluminosilicate (Q) and carbon nanotubes (CNTs) modified with zinc nanoparticles (ZnNPs) as alternative adsorbent materials for OTC removal. The ZnNPs were synthesized by chemical reduction method and were used to modify the Q and CNT surface. There were obtained four materials (Q, Q/ZnNPs CNTs. and CNTs/ZnNPs) characterized by SEM–EDX, FTIR, DRX, and pHPZC. The adsorption behavior of OTC, as a function of drug concentration, pH, and temperature, was investigated by adsorption experiments. High adsorption capacities (qe) of OTC as 644 and 111 mg/g were obtained for CNTs and CNTs/ZnNPs, respectively. For Q and Q/ZnNPs, the maximum OTC sorption was 177 and 78 mg/g, respectively. It was found that OTC adsorption process using CNTs and CNTs/ZnNPs follows a pseudo-second-order and intraparticle diffusion, while when using the Q and Q/Zn, it follows a pseudo-first-order model. Moreover, isotherm tests were performed on distilled water and drinking water to evaluate the effect of ionic strength. The obtained data were adjusted to Langmuir, Freundlich, Temkin, and Dubinin-Raduskevich isotherm equations, being Freundlich the isotherm that describes the OTC sorption process. The results obtained were indicative of a good OTC adsorption capacity by the alternative prepared materials

Exosomes-Based Nanomedicine for Neurodegenerative Diseases: Current Insights and Future Challenges

Neurodegenerative diseases constitute a group of pathologies whose etiology remains unknown in many cases, and there are no treatments that stop the progression of such diseases. Moreover, the existence of the blood–brain barrier is an impediment to the penetration of exogenous molecules, including those found in many drugs. Exosomes are extracellular vesicles secreted by a wide variety of cells, and their primary functions include intercellular communication, immune responses, human reproduction, and synaptic plasticity. Due to their natural origin and molecular similarities with most cell types, exosomes have emerged as promising therapeutic tools for numerous diseases. Specifically, neurodegenerative diseases have shown to be a potential target for this nanomedicine strategy due to the difficult access to the brain and the strategy’s pathophysiological complexity. In this regard, this review explores the most important biological-origin drug delivery systems, innovative isolation methods of exosomes, their physicochemical characterization, drug loading, cutting-edge functionalization strategies to target them within the brain, the latest research studies in neurodegenerative diseases, and the future challenges of exosomes as nanomedicine-based therapeutic tools

Alcoholic extracts from Paulownia tomentosa leaves for silver nanoparticles synthesis

Paulownia tomentosa (P. tomentosa) is a hardwood tree that has economic and scientific relevance but has no use as food. For that reason, we selected it to conduct a study on the synthesis of silver nanoparticles (AgNPs) using hydroalcoholic extracts from its leaves. Phytochemical sources had been widely used as reducing agents for synthesis of nanoparticles. Our work is the first approach for studying the correlation between the composition of the extracts and the AgNPs synthesis features. Isopropyl alcohol, ethanol, and water were proposed as extraction solvents. Nanoparticles were characterized by UV–vis, FTIR, and Scanning Electron Microscopy/Energy Dispersive X-ray spectroscopy (SEM/EDX) and the Antimicrobial activity was evaluated. Our findings suggest that the composition of the extracts varies with the selection of the extraction solvent. This is relevant because solvents with similar characteristics and polarity (isopropyl alcohol and ethanol) produced different AgNPs features such as ζ potential that was −20.5 ± 0.41, −25 ± 0.12 and 31 ± 0.79 mV for samples extracted with isopropyl alcohol, ethanol, and water, respectively. Samples obtained with isopropyl alcohol produced nanoparticles with the highest antioxidant activity and stability. Also, we found that size, shape, reaction kinetics, and bactericidal properties have a strong correlation with the composition of the plant extract. Our results justify the use of a wide range of extraction solvents to obtain detail implications on size and shape of nanoparticles, and the use of chromatographic techniques to determine each fraction composition. Our investigation is the first step in a coherent path to propose reaction mechanisms on nanoparticles synthesis using complex mixtures from Paulownia tomentosa extracts. Keywords: Biosynthesis, Silver nanoparticles (AgNPs), Paulownia tomentosa, Electrochemical-CUPRAC, Trolox Equivalent Antioxidant Capacity, Flavonoid oxidatio

Quorum sensing network in clinical strains of A. baumannii : AidA is a new quorum quenching enzyme

Acinetobacter baumannii is an important pathogen that causes nosocomial infections generally associated with high mortality and morbidity in Intensive Care Units (ICUs). Currently, little is known about the Quorum Sensing (QS)/Quorum Quenching (QQ) systems of this pathogen. We analyzed these mechanisms in seven clinical isolates of A. baumannii. Microarray analysis of one of these clinical isolates, Ab1 (A. baumannii ST-2-clon-2010), previously cultured in the presence of 3-oxo-C12-HSL (a QS signalling molecule) revealed a putative QQ enzyme (α/β hydrolase gene, AidA). This QQ enzyme was present in all nonmotile clinical isolates (67% of which were isolated from the respiratory tract) cultured in nutrient depleted LB medium. Interestingly, this gene was not located in the genome of the only motile clinical strain growing in this medium (A. baumannii strain Ab421-GEIH-2010 [Ab7], isolated from a blood sample). The AidA protein expressed in E. coli showed QQ activity. Finally, we observed downregulation of the AidA protein (QQ system attenuation) in the presence of HO (ROS stress). In conclusion, most of the A. baumannii clinical strains were not surface motile (84%) and were of respiratory origin (67%). Only the pilT gene was involved in surface motility and related to the QS system. Finally, a new QQ enzyme (α/β hydrolase gene, AidA protein) was detected in these strains

Biodiversidad 2016. Estado y Tendencias de la Biodiversidad Continental de Colombia

Esta tercera entrega del reporte anual de la biodiversidad en Colombia profundiza en la línea editorial iniciada el año 2014 mediante nuevas propuestas analíticas y gráficas, con la intención de garantizar que la información llegue a todos los públicos y pueda ser discutida de manera amena sin sacrificio de calidad. La apuesta comunicativa sigue siendo central en el proyecto institucional y los nuevos lenguajes con los que estamos aprendiendo a conversar con la sociedad y las instituciones son un experimento que esperamos sea cada vez más satisfactorio: ya estamos construyendo la versión 2017 con el apoyo de las nuevas tecnologías digitales de manera que la potencia de la conexión vital colombiana se exprese en toda su capacidad. Por los contenidos es evidente que aún distamos mucho de tener una capacidad de seguimiento sistemático para la mayoría de temas relativos a la gestión de la biodiversidad y los servicios ecosistémicos, la única manera de evaluar si las medidas de política y las inversiones que realiza la sociedad están teniendo los efectos deseados. De hecho, parte de las limitaciones reconocidas por robustamente los cambios positivos o negativos que afectan los diferentes niveles de organización de la vida planetaria, por lo cual las mismas metas de Aichi, nuestra carta de navegación global, están pendientes de verificación. Un propósito adicional de este proceso es la invitación a todos los colombianos para contribuir con la construcción y alimentación de los indicadores básicos de seguimiento a la gestión, ya que es imposible identificar las tendencias de largo plazo en que están inmersas la flora y fauna colombianas sin el apoyo de las instituciones, los investigadores y los ciudadanos: en el país de la megadiversidad, el reto es inmenso. Por este motivo, este reporte irá abriendo sus páginas a expertos, incluso indígenas o de comunidades locales, para que presenten de manera sistemática y documentada sus perspectivas del cambio ambiental y sus efectos en la biodiversidad, con el ánimo de promover el compromiso de todos en su gestión. La única manera de superar el riesgo de extinción es mediante un activo proceso de aprendizajes sociales que haga que todos los sectores asuman una parte de la compleja responsabilidad que significa proteger todas las formas de vida del país, una décima parte mal contada de las planetarias. Agradezco a las decenas de personas que contribuyeron con este reporte, a quienes nos han apoyado en todas las etapas de producción y a sus lectores y usuarios, quienes son en último término los jueces de su utilidad.Bogotá, D. C