Diagnostic performance of a point-of-care molecular system for the detection of SARS-CoV-2 in Peru. / Rendimiento diagnóstico de un sistema molecular de uso en el punto de atención para la detección de SARS-CoV-2 en Perú.

The present study assessed the diagnostic performance of the Xpert®Xpress SARS-CoV-2 test in comparison with the Charité protocol real-time RT PCR for the detection of SARS-CoV-2 in Peruvian patients. This was a diagnostic test study that included 100 nasal and pharyngeal swab samples. We obtained an overall concordance of 98.70% (95%CI: 92.98-99.97), with a kappa coefficient of 0.97 (95%CI: 0.86-1.00) and sensitivity and relative specificity rates of 100% and 96.15%, respectively. Additionally, the percentage of the area under the ROC curve was 98.08% in both cases, and an analytical specificity rate of 100% was obtained for the different respiratory viruses evaluated. In conclusion, the Xpert®Xpress SARS-CoV-2 test, by using nasal and pharyngeal swab samples, was highly sensitive and specific, and the kappa coefficient showed an excellent correlation when compared to the reference test. Motivation for the study. To describe and evaluate a closed molecular platform, easy to use and of importance in Peru for the management of diseases of public health priority, now implemented for the detection of SARS-CoV-2. Main findings. Highly sensitive and specific molecular test, with excellent correlation compared to the reference test for detecting SARS-CoV-2. Implications. Can be used in point-of-care laboratories for rapid molecular detection of different infectious agents, including SARS-CoV-2. Little expertise and minimal infrastructure are required to implement it.

En el presente estudio se estimó el rendimiento diagnóstico de la prueba Xpert®Xpress SARS-CoV-2 en comparación con la RT PCR en tiempo real-protocolo Charité, para la detección de SARS-CoV-2 en pacientes peruanos. Se trató de un diseño de prueba diagnóstica que incluyó 100 muestras de hisopado nasal y faríngeo. Se obtuvo una concordancia global de 98,70% (IC95%: 92,98-99,97), con un coeficiente kappa de 0,97 (IC95%: 0,86-1.00); se estimó una sensibilidad y especificad relativa de 100% y 96,15%, respectivamente. Adicionalmente, el porcentaje del área bajo la curva ROC fue 98,08% en ambos casos y se obtuvo una especificidad analítica del 100% para los diferentes virus respiratorios evaluados. En conclusión, la prueba Xpert®Xpress SARS-CoV-2 a partir de muestras de hisopado nasal y faríngeo fue altamente sensible y específica, así mismo el coeficiente kappa mostró una excelente correlación, al compararla con la prueba de referencia. Motivación para realizar el estudio. Descripción y evaluación de una plataforma molecular cerrada, de fácil uso y de importancia en el Perú para el manejo de enfermedades de prioridad en salud pública, ahora implementada para la detección de SARS-CoV-2. Principales hallazgos. Prueba molecular altamente sensible y específica, con una correlación excelente con respecto al referente para detectar SARS-CoV-2. Implicancias. Puede ser utilizada en los laboratorios que se encuentran en los puntos de atención del paciente para la detección molecular rápida de diferentes agentes infecciosos, incluido el SARS-CoV-2. Se necesita poca experticia y mínima infraestructura para poder implementarla.

Rendimiento diagnóstico de un sistema molecular de uso en el punto de atención para la detección de SARS-CoV-2 en Perú / Diagnostic performance of a point-of-care molecular system for the detection of SARS-CoV-2 in Peru

RESUMEN En el presente estudio se estimó el rendimiento diagnóstico de la prueba Xpert®Xpress SARS-CoV-2 en comparación con la RT PCR en tiempo real-protocolo Charité, para la detección de SARS-CoV-2 en pacientes peruanos. Se trató de un diseño de prueba diagnóstica que incluyó 100 muestras de hisopado nasal y faríngeo. Se obtuvo una concordancia global de 98,70% (IC95%: 92,98-99,97), con un coeficiente kappa de 0,97 (IC95%: 0,86-1.00); se estimó una sensibilidad y especificad relativa de 100% y 96,15%, respectivamente. Adicionalmente, el porcentaje del área bajo la curva ROC fue 98,08% en ambos casos y se obtuvo una especificidad analítica del 100% para los diferentes virus respiratorios evaluados. En conclusión, la prueba Xpert®Xpress SARS-CoV-2 a partir de muestras de hisopado nasal y faríngeo fue altamente sensible y específica, así mismo el coeficiente kappa mostró una excelente correlación, al compararla con la prueba de referencia.

ABSTRACT The present study assessed the diagnostic performance of the Xpert®Xpress SARS-CoV-2 test in comparison with the Charité protocol real-time RT PCR for the detection of SARS-CoV-2 in Peruvian patients. This was a diagnostic test study that included 100 nasal and pharyngeal swab samples. We obtained an overall concordance of 98.70% (95%CI: 92.98-99.97), with a kappa coefficient of 0.97 (95%CI: 0.86-1.00) and sensitivity and relative specificity rates of 100% and 96.15%, respectively. Additionally, the percentage of the area under the ROC curve was 98.08% in both cases, and an analytical specificity rate of 100% was obtained for the different respiratory viruses evaluated. In conclusion, the Xpert®Xpress SARS-CoV-2 test, by using nasal and pharyngeal swab samples, was highly sensitive and specific, and the kappa coefficient showed an excellent correlation when compared to the reference test.

Potencial dendrocronológico de tres especies de Podocarpáceas de la Cordillera de los Andes / Dendrochronological potential of three Podocarpaceae species from the Andean Cordillera

Resumen Introducción: Poco se conoce del potencial dendrocronológico de las Podocarpáceas en el trópico. Objetivo: Explorar el potencial dendrocronológico de tres especies de podocarpáceas: Retrophyllum rospigliosii, Podocarpus oleifolius y Prumnopitys harmsiana. Métodos: De plantaciones no manejadas localizadas en los Andes colombianos, se muestrearon y analizaron 88 árboles: 30 muestras de R. rospigliosii provenientes de secciones transversales, 30 y 28 muestras de P. oleifolius y P. harmsiana, respectivamente, provenientes de núcleos de madera extraídos con barreno de incrementos. Las muestras se procesaron siguiendo las técnicas dendrocronológicas estándar. Resultados: En general, las características anatómicas de los anillos de crecimiento son similares para las tres especies, con una anatomía simple de traqueidas alineadas radialmente por tratarse de coníferas. Dado que la edad conocida de la plantación coincide con el número de anillos se considera una fuerte evidencia de la frecuencia anual de su formación en R. rospigliosii y P. oleifolius, las cuales presentaron buena sincronización (cofechado) con una inter-correlación promedio de 0.55 (r-Pearson). Para P. harmsiana no fue posible concretar series de ancho de anillos de las muestras recolectadas. Las series estandarizadas de R. rospigliosii y P. oleifolius mostraron una relación con los registros instrumentales de precipitación y temperatura, indicando que estas especies pueden ser promisorias para estudios adicionales. Conclusión: La investigación dendrocronología con especies de Podocarpáceas podría realizarse exitosamente con R. rospigliosii y P. oleifolius, pero no con P. harmsiana.

Abstract Introduction: Little is known about the dendrochronological potential of Podocarpaceaes in the tropics. Objective: To explore the dendrochronological potential of three Podocarpaceae species: Retrophyllum rospigliosii, Podocarpus oleifolius, and Prumnopitys harmsiana. Methods: From a non-managed plantation in the Andean cordillera in Colombia, a total of 88 trees were analyzed: 30 samples of cross-sections of R. rospigliosii, and 30 and 28 samples of P. oleifolius and P. harmsiana, respectively, obtained with an increment borer. Samples were processed according to standard dendrochronological methods. Results: The anatomical characteristics of the growth rings of the three species are similar, with a simple conifer anatomy with radially oriented tracheids. Since the known age of the plantation coincides with the number of tree rings this is strong evidence of annual tree-ring frequency of R. rospigliosii and P. oleifolius which also showed a satisfactory cross-dating with an average inter-correlation of 0.55 (r-Pearson). For P. harmsiana, it was not possible to build a tree-ring series from the collected samples. R. rospigliosii and P. oleifolius standardized ring-width chronologies showed a relationship with the instrumental records of rainfall and temperature, indicating these species may be promising further studies. Conclusions: Dendrochronological research with Podocarpaceae species could be carried out successfully with R. rospigliosii and P. oleifolius but not with P. harmsiana.

Tetracoordinate Co(II) complexes with semi-coordination as stable single-ion magnets for deposition on graphene.

We present a theoretical and experimental study of two tetracoordinate Co(II)-based complexes with semi-coordination interactions, i.e., non-covalent interactions involving the central atom. We argue that such interactions enhance the thermal and structural stability of the compounds, making them appropriate for deposition on substrates, as demonstrated by their successful deposition on graphene. DC magnetometry and high-frequency electron spin resonance (HF-ESR) experiments revealed an axial magnetic anisotropy and weak intermolecular antiferromagnetic coupling in both compounds, supported by theoretical predictions from complete active space self-consistent field calculations complemented by N-electron valence state second-order perturbation theory (CASSCF-NEVPT2), and broken-symmetry density functional theory (BS-DFT). AC magnetometry demonstrated that the compounds are field-induced single-ion magnets (SIMs) at applied static magnetic fields, with slow relaxation of magnetization governed by a combination of quantum tunneling, Orbach, and direct relaxation mechanisms. The structural stability under ambient conditions and after deposition was confirmed by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Theoretical modeling by DFT of different configurations of these systems on graphene revealed n-type doping of graphene originating from electron transfer from the deposited molecules, confirmed by electrical transport measurements and Raman spectroscopy.

On the importance of temporal floc size statistics and yield strength for population balance equation flocculation model.

Many aquatic environments contain cohesive sediments that flocculate and create flocs with a wide range of sizes. The Population Balance Equation (PBE) flocculation model is designed to predict the time-dependent floc size distribution and should be more complete than models based on median floc size. However, a PBE flocculation model includes many empirical parameters to represent important physical, chemical, and biological processes. We report a systematic investigation of key model parameters of the open-source PBE-based size class flocculation model FLOCMOD (Verney, Lafite, Claude Brun-Cottan and Le Hir, 2011) using the measured temporal floc size statistics reported by Keyvani and Strom (2014) at a constant turbulent shear rate S. Results show that the median floc size d50, in terms of both the equilibrium floc size and the initial floc growth, is insufficient to constrain the model parameters. A comprehensive error analysis shows that the model is capable of predicting three floc size statistics d16, d50 and d84, which also reveals a clear trend that the best calibrated fragmentation rate (inverse of floc yield strength) is proportional to the floc size statistics considered. Motivated by this finding, the importance of floc yield strength is demonstrated in the predicted temporal evolution of floc size by modeling the floc yield strength as microflocs and macroflocs giving two corresponding fragmentation rates. The model shows a significantly improved agreement in matching the measured floc size statistics.

Deposition of Tetracoordinate Co(II) Complex with Chalcone Ligands on Graphene.

Studying the properties of complex molecules on surfaces is still mostly an unexplored research area because the deposition of the metal complexes has many pitfalls. Herein, we probed the possibility to produce surface hybrids by depositing a Co(II)-based complex with chalcone ligands on chemical vapor deposition (CVD)-grown graphene by a wet-chemistry approach and by thermal sublimation under high vacuum. Samples were characterized by high-frequency electron spin resonance (HF-ESR), XPS, Raman spectroscopy, atomic force microscopy (AFM), and optical microscopy, supported with density functional theory (DFT) and complete active space self-consistent field (CASSCF)/N-electron valence second-order perturbation theory (NEVPT2) calculations. This compound's rationale is its structure, with several aromatic rings for weak binding and possible favorable π-π stacking onto graphene. In contrast to expectations, we observed the formation of nanodroplets on graphene for a drop-cast sample and microcrystallites localized at grain boundaries and defects after thermal sublimation.

Preferencias de empleo de las estudiantes de doctorado en Ingeniería

Resumen Este artículo analiza las preferencias de empleo de las mujeres estudiantes de doctorado en Ingeniería. Estas preferencias oscilan entre la academia y la industria y se las compara con las de los estudiantes hombres. Trabajos previos de investigación sobre mujeres con doctorado se han enfocado en el clima laboral, las experiencias de acoso sexual, el impacto de los factores familiares en la trayectoria laboral y los ingresos salariales. El análisis está basado en información obtenida de una encuesta virtual aplicada a estudiantes de doctorado en ingeniería provenientes de una universidad en Colombia. Los resultados muestran que las estudiantes mujeres tienen mayor interés por espacios laborales en los cuales puedan realizar investigación y tienen una alta valoración por atributos laborales como la posibilidad de colaborar con otras instituciones /organizaciones. Una de las principales conclusiones del estudio es que las mujeres presentaron mayor inclinación por los atributos laborales que caracterizan a la academia mientras que los hombres evidencian una mayor por los relacionados con la industria y se mostraron menos interesados en optar por una carrera académica.

Abstract This paper analyses career preferences of women who are doing a Ph.D. program in engineering and compares them with those of men doing a Ph.D. program in engineering. Research on women with doctoral education has focused on exploring topics related to job climate, sexual harassment, the impact of family factors on job experience, employability, and salary earnings. The analysis is based on data collected from online survey administered to women doing a Ph.D. program in engineering at a university in Colombia. The results show that women have an interest in jobs in which they can do research as well as a high perception over job attributes, such collaboration with institutions/organization. One of the main conclusions of the study is that women show greater inclination for the work attributes of the academy while men show a greater tendency for those related to the industry and men are less interested in an academic career.

Implante de membrana amniótica en la corrección de úlceras corneales profundas de caninos y felinos / Amniotic membrane implant in the correction of deep corneal ulcers in canines and felines / Implante de membrana amniótica na correção de úlceras corneais profundas de caninos e felinos

Resumen Antecedentes: gran parte de los defectos del epitelio corneal, como las queratitis ulcerativas, no responden al tratamiento convencional y progresan a ulceración estromal y perforación inminente. En busca de nuevas opciones terapéuticas para corregir dichos defectos corneales, se encuentran el uso de membrana amniótica y las plastias corneales, ambos tratamientos quirúrgicos buscan una reepitelización corneal y un adecuado proceso de cicatrización cuando el tratamiento médico no ha tenido éxito. Objetivos: por medio de este trabajo se busca analizar los estudios actualizados referentes a los implantes de membrana amniótica para la resolución de úlceras corneales profundas en caninos y felinos, para poder definir los principios terapéuticos de la membrana amniótica en patologías oculares, determinar un protocolo de preparación de injertos de membrana amniótica y servir de base para estudios prácticos acerca de implantes corneales en caninos y felinos en Colombia. Conclusiones: con base en los resultados obtenidos en el proceso de revisión documental y en la experiencia quirúrgica de los autores, puede concluirse que el uso de la membrana amniótica apoya el crecimiento del epitelio de la superficie ocular y facilita la migración de las células epiteliales, proporciona una barrera a la infección, promueve la revitalización y mejora el dolor. Gracias a sus características únicas ofrece una opción importante en el tratamiento de úlceras corneales. En los últimos años su eficacia ha sido demostrada en el tratamiento de las enfermedades de la superficie ocular, y es ampliamente utilizada en este tipo de patologías.

Abstract Introduction: Most defects of the corneal epithelium, such as ulcerative keratitis, do not respond to conventional treatment and they progress to stromal ulceration and imminent perforation. Among new therapeutic options to correct these corneal defects, there is the use of amniotic membrane and corneal plasties; both surgical treatments seek a corneal reepithelialization and an adequate healing process when medical treatment has not been successful. Objectives: This work seeks to analyze updated studies concerning amniotic membrane implants for the solution of deep corneal ulcers in canines and felines, in order to define the therapeutic principles of amniotic membrane in ocular pathologies, determine a protocol for the preparation of amniotic membrane grafts, and serve as a basis for practical studies about corneal implants in canines and felines in Colombia. Conclusions: Based on the results obtained during the document review process and the surgical experience of the authors, it can be concluded that the use of amniotic membrane supports the growth of the ocular surface epithelium and facilitates the migration of epithelial cells, provides a barrier to infection, promotes revitalization, and ameliorates pain. Thanks to its unique characteristics, it is an excellent option in the treatment of corneal ulcers. In recent years, its effectiveness has been demonstrated in the treatment of ocular surface diseases, and is widely used in this type of pathologies.

Resumo Antecedentes: grande parte dos defeitos do epitélio corneano, como as queratites ulcerativas, não respondem ao tratamento convencional e progridem a ulceração estroma e perfuração iminente. Na busca de novas opções terapêuticas para corrigir estes defeitos corneais, encontram-se o uso de membrana amniótica e as reparações corneais, ambos tratamentos cirúrgicos buscam uma reepitelização da córnea e um adequado processo de cicatrização quando o tratamento médico não foi bem sucedido. Objetivos: por meio deste trabalho se busca analisar os estudos atualizados referentes aos implantes de membrana amniótica para a resolução de úlceras corneais profundas em caninos e felinos, para poder definir os princípios terapêuticos da membrana amniótica em patologias oculares, determinar um protocolo de preparação de enxertos de membrana amniótica e servir de base para estudos práticos sobre os implantes corneais em caninos e felinos na Colômbia. Conclusões: com base nos resultados obtidos no processo de revisão documental e na experiência cirúrgica dos autores, pode concluir-se que o uso da membrana amniótica apoia o crescimento do epitélio da superfície ocular e facilita a migração das células epiteliais, proporciona uma barreira à infecção, promove a revitalização e melhora a dor. Graças a suas características únicas oferece uma opção importante no tratamento de úlceras corneais. Nos últimos anos a sua eficácia tem sido demonstrada no tratamento das doenças da superfície ocular, e é amplamente utilizada neste tipo de patologias.

Características clínicas y microbiológicas de pacientes con periodontitis agresiva generalizada / Clinical and microbiological characteristics of a patients with generalized aggressive periodontitis

RESUMEN: Objetivo: el objetivo de este estudio es describir las características clínicas y microbiológicas de una muestra de pacientes diagnosticados con periodontitis agresiva generalizada (PAgG). Materiales y métodos: En este estudio de corte transversal, 20 sujetos menores de 30 años con PAgG atendidos en las clínicas odontológicas de la Universidad de Antioquia en Medellín Colombia, fueron invitados a participar entre diciembre del 2015 y marzo del 2017, las muestras microbiológicas fueron analizadas usando técnicas de cultivo y tomadas en los seis sitios más profundos de cada paciente (≥ 5mm). Resultados: Prevotella ssp y F. nucleatum fueron detectados en altos porcentajes, Porphyromonas gingivalis (P.g) fue positivo para la mitad de los sujetos estudiados; además de los microorganismos comúnmente estudiados, el 10% de los pacientes fueron positivos para bacilos entéricos gram-negativos. Conclusiones: se observaron grandes proporciones de microorganismos que incluyeron Prevotella spss y F. nucleatum; el 10% de los pacientes fueron positivos para bacilos entéricos gram-negativos.

ABSTRACT: Aim: The aim of this study is to describe the clinical and microbiological characteristics of a sample of patients diagnosed with generalized aggressive periodontitis (PAgG). Materials and methods: In this cross-sectional study, 20 subjects under 30 years of age with PAgG treated at the dental clinics of the University of Antioquia in Medellín, Colombia were invited to participate between December 2015 and March 2017, the microbiological samples analyzed using culture techniques were taken at the six deepest sites of each patient (≥ 5mm). Results: Prevotella ssp and F. nucleatum were detected in high percentages, Porphyromonas gingivalis (P.g) was positive for half of the studied subjects; In addition to the microorganisms commonly studied, 10% of the patients were positive for gram-negative enteric bacilli. Conclusions: large proportions of microorganisms were observed, including Prevotella spss and F. nucleatum; 10% of the patients were positive for gram-negative enteric bacilli.

Arteritis de Takayasu y formación inusual de aneurisma gigante de arteria pulmonar, reporte de un caso / Takayasu arteritis and giant aneurysm of pulmonary artery, Case report

RESUMEN La arteritis de Takayasu es una de las vasculitis de grandes vasos que afecta a la aorta y a sus ramas principales, llevando a estenosis arterial y, en ocasiones, a trombosis. También se observa la formación de aneurismas en la circulación general. No tiene un tratamiento específico. La terapia de elección son los corticoides, seguidos de otros inmunosupresores en casos de no lograrse un control adecuado del proceso inflamatorio. Se reporta el caso de un paciente con arteritis de Takayasu, con formación inusual de aneurisma gigante de la arteria pulmonar.

ABSTRACT Takayasu arteritis is a large vessel vasculitis that affects the aorta and its main branches, leadingto arterial stenosis, and occasionally, thrombosis. There is also aneurysm formation in the general circulation. There is no specific treatment. The therapy of choice is corti-costeroids, followed by other immunosuppressants in cases where adequate control of the inflammatory process is not achieved. A case is presented of a patient with Takayasu arteritis and the unusual presence of giant aneurysm of pulmonary artery.

Efecto inmunomodulador anti-inflamatorio de la moxifloxacina como coadyuvante en la terapia periodontal / Immunomodulatory anti-inflammatory effect of moxifloxacin as an adjunct in periodontal therapy

Fundamento: la periodontitis es una enfermedad infecciosa que se presenta como producto de la interacción entre algunos microorganismos y diversas reacciones del huésped a la infección. La función inmunomodulatoria anti-inflamatoria de antimicrobianos como la moxifloxacina puede ser una cualidad de gran utilidad en el tratamiento de la periodontitis. Objetivo: revisar la literatura científica con el fin de determinar si la moxifloxacina presenta un efecto inmunomodulador. Métodos: se realizó una revisión sistemática de investigaciones realizadas en humanos o células humanas publicadas en las bases de datos Medline-Pubmed, SciELO, LILACS y Google académico entre 1996 y 2015, se utilizaron los siguientes términos en diferentes combinaciones: moxifloxacin, immunomodulation, cytokines, interleukines y tumor necrosisfactor. Se excluyeron las series de casos, resultados duplicados debido a las combinaciones de los términos de búsqueda, datos no disponibles, cartas al editor y revisiones históricas. Desarrollo: un total de nueve estudios presentaron disminución de la liberación de las interleuquinas1β, 6, 8 mientras que cinco estudios mostraron su inhibición. Tres publicaciones demostraron inhibición del factor de necrosis tumoral α y tres presentaron reducción de su liberación. Conclusiones: la moxifloxacina, además de su eficacia contra los principales periodontopatógenos, tiene un efecto inmunomodulador importante en el proceso inflamatorio de la periodontitis que debe tenerse en cuenta en la toma de decisiones clínicas para el tratamiento de esta enfermedad.

Background: periodontitis is an infectious disease that occurs as a result of the interaction between microorganisms and some different reactions of the host to infection. The anti-inflammatory immunomodulatory function of antimicrobial drugs such as moxifloxacin can be a useful quality in the treatment of periodontitis. Objective: to review the scientific literature related to the immunomodulatory effect of moxifloxacin. Methods: a systematic review of research conducted in humans or human cells published in Medline-Pubmed, SciELO, LILACS and academic Google between 1996 and 2015 data was performed using the following terms in different combinations: moxifloxacin, immunomodulation, cytokines, interleukins and tumor necrosis factor. Case series, duplicate results due to combinations of search terms, missing data, letters to the editor and historical revisions, were excluded. Development: a total of nine studies showed decreased release of the interleukins 1β, 6, 8, while five studies showed inhibition. Similarly, three publications showed inhibition of tumor necrosis factor α and three arranged reduction of their release. Conclusions: moxifloxacin, besides its effectiveness against the main periodontopathogens, has a significant immunomodulatory effect in the inflammatory process of periodontitis to be taken into account in the clinical decision to treat this disease.

Feasibility and Operational Performance of Tuberculosis Detection by Loop-Mediated Isothermal Amplification Platform in Decentralized Settings: Results from a Multicenter Study.

Currently available nucleic acid amplification platforms for tuberculosis (TB) detection are not designed to be simple or inexpensive enough to implement in decentralized settings in countries with a high burden of disease. The loop-mediated isothermal amplification platform (LAMP) may change this. We conducted a study in adults with symptoms suggestive of TB in India, Uganda, and Peru to establish the feasibility of using TB-LAMP (Eiken Chemical Co.) in microscopy laboratories compared with using smear microscopy against a reference standard of solid and liquid cultures. Operational characteristics were evaluated as well. A total of 1,777 participants met the eligibility criteria and were included for analysis. Overall, TB-LAMP sensitivities among culture-positive samples were 97.2% (243/250; 95% confidence interval [CI], 94.3% to 98.2%) and 62.0% (88/142; 95% CI, 53.5% to 70.0%) for smear-positive and smear-negative TB, respectively, but varied widely by country and operator. Specificities ranged from 94.5% (446/472; 95% CI, 92.0% to 96.4%) to 98.0% (350/357; 95% CI, 96.0% to 99.2%) by country. A root cause analysis identified high temperatures, high humidity, and/or low reaction volumes as possible causes for false-positive results, as they may result in nonspecific amplification. The study was repeated in India with training focused on vulnerable steps and an updated protocol; 580 participants were included for analysis. Specificity in the repeat trial was 96.6% (515/533; 95% CI, 94.7% to 97.9%). To achieve acceptable performance of LAMP at the microscopy center level, significant training and infrastructure requirements are necessary.

Flood-promoted vessel formation in Prioria copaifera trees in the Darien Gap, Colombia.

Trees growing in floodplains develop mechanisms by which to overcome anoxic conditions. Prioria copaifera Griseb. grows on the floodplains of the Atrato River, Colombia, and monodominant communities of this species remain flooded for at least 6 months a year. The aims of this study were as follows: (i) to compare variations in tree-ring structure with varying river water levels; and (ii) to reconstruct variations in water levels from the chronology of variations in the porosity of the tree rings. Discs were taken from 12 trees, and the number of vessels along 3-mm-wide radial transects was counted. Standard dendrochronological techniques were used to determine the mean number of vessels over 130 years, between 1877 and 2006; the signal-to-noise ratio was 13.3 and the expressed population signal 0.93. Furthermore, this series of vessel numbers was calibrated against variations in the water levels between 1977 and 2000; positive correlations were found with the mean for both the annual river water level and the level from June to August. The transfer function between the principal components of the mean annual water level and those of chronology allowed us to reconstruct the river levels over 130 years. Our conclusions are as follows: (i) the number of vessels per ring is an appropriate proxy for determining variations in water levels; and (ii) P. copaifera grows thicker and produces more vessels when water levels rise. The probable ecophysiological causes of this interesting behaviour are discussed.

Trombolisis para Tromboembolismo pulmonar masivo en el servicio de urgencias: Reporte de un caso / Thrombolysis in massive pulmonary embolism in emergency room: case report

El tromboembolismo pulmonar (TEP) es una posibilidad diagnóstica que obliga a determinar una probabilidad a través del puntaje (score) de Wells, con el fin de evitar subdiagnósticos o realizar diagnósticos tardíos en el servicio de urgencias. En ocasiones el TEP se presenta como una condición amenazante de la vida que requiere intervención inmediata, siendo la trombolisis el tratamiento adecuado cuando se acompaña de inestabilidad hemodinámica y no hay contraindicaciones para su realización. Se presenta el caso de un hombre de 61 años que ingresa a un servicio de urgencias de alto nivel de complejidad, con diagnóstico de TEP masivo y se procede a trombolisis con Alteplase®, obteniéndose adecuada reperfusión de la circulación pulmonar y estabilidad cardiorrespiratoria luego de realizar el procedimiento.

Pulmonary thromboembolism (PTE) is a diagnosis possibility that implies determining a probability with Wells score in order to avoid subdiagnosis or late diagnosis in emergency services. In some occasions, it presents as a life threatening condition that requires immediate intervention. Thrombolysis is the adequate treatment when PTE is accompanied with hemodynamic instability and when there are no counter-indications. The following article describes the case of a 61 year old man who enters a high complexity level emergency service with a diagnosis of massive PTE and thrombolysis is carried out with Alteplase ®. Adequate reperfusion of pulmonary circulation is obtained as well as cardio respiratory stability following the procedure.

Identificación electroforética de α2-macroglobulina en plasma de ovino de pelo (Ovis aries) y búfalo (Bubalus bubalis) / Electrophoretic identification of α2-macroglobulin in the plasma of tropical hair sheep (Ovis aries) and buffalo (Bubalus bubalis)

A través del presente estudio se analizaron plasmas sanguíneos de seis especies, incluyendo el humano tanto en estado gestante como no gestante, identificándose por primera vez en plasma, la glicoproteína α2-Macroglobulina (α2-M) de ovino de pelo (Ovis aries) y de búfalo (Bubalus bubalis). La presencia de esta proteína en el plasma sanguíneo de todas las especies en estudio se demostró mediante electroforesis en gel de poliacrilamida usando sodio dodecilsulfato como agente denaturante (SDS PAGE) al 7.5% identificándose como bandas de 180 kDa y en forma no denaturante PAGE 5% como bandas de 720 kDa. Estas últimas bandas fueron claramente intercambiables de la forma tetramérica a la forma monomérica en los ensayos electroforéticos. Como controles se usaron la α2-M (tetramérica) y la proteína de la zona de gestación (PZP) (dimérica) purificadas a un 98%; así como, las bandas de estas dos proteínas en el plasma humano. El análisis de la secuencia del dominio N-terminal de la (α2-M) de ovino de pelo, fue muy similar al de la proteína humana purificada. Tanto la α2-M humana como la bovina llegaron a ser activadas a la forma rápida por medio de la reacción con metilamina. Lo anterior demuestra diferencias en la reactividad de las α2-M animales con la amina primaria cuando se comparan los resultados con la forma rápida de la α2-M humana. Será necesario unificar los métodos de purificación de esta proteína en todas las especies, de tal manera que los dominios sensibles de las α-macroglobulinas (tioιster y región señuelo) tengan el mismo tratamiento y el mismo grado de desnaturalización para todas las preparaciones de α2-M.

Blood plasma from six different non pregnant and pregnant species, including human blood plasma, was analyzed for detection of α2-Macroglobulin (α2-M). The tropical hair sheep (Ovis aries) and the buffalo (Bubalus bubalis) were studied for the first time in Colombia. The presence of the α2-M in plasma of all the species was demonstrated by SDS 7.5% PAGE as bands of 180 kDa as well as by non-denaturing 5% PAGE with bands of 720 kDa. The tetrameric form α2-M (tetramérica) and the pregnancy zone protein (PZP) (dimeric) purified at 98%, as well as its corresponding bans from human plasma were used as control. The N-terminal sequence of the band of 180 kDa in Tropical hair sheep plasma was very similar to the purified human α2-M. The results indicated the presence of α2-M in blood plasma of all the species tested, while the PZP was present only in the pregnant human plasma. Both human and bovine α2-M became activated with the fast form by reacting with Methylamine. This Fac. demonstrates the differences in the reactivity of the animal’s α2-M with primary amine as compared with the human α2-M. It could be necessary to unify purification methods into one method for all species, so that the sensitive domain of the α-macroglobulins (thiolester and bait region) receives the same treatment and grade of denaturation for all α2-M preparation.

Diseño de un instrumental para fijación de columna dorsal y lumbar / Design of an instrument for setting and lumbar spine

Se elaboró un trabajo de tipo experimental en el cual se planteó como objetivo esencial el diseño de un instrumental para fijación anterior de columna que reuniera las normas mínimas de biocompatibilidad, versatilidad en su aplicación y resistencia a las cargas mecánicas reportadas en la literatura como válidas para este tipo de elementos. Para hacer el diseño del instrumento se revisó la literatura acerca de los sistemas existentes en el mercado, tanto aquellos de uso rutinario como los de tipo experimental, y se buscó adecuar un sistema nuevo que cumpliera con especificaciones mínimas, pero que a la vez fuera de bajo costo y fácil aplicación. El proceso de investigación fue desarrollado en tres fases.