Open Source Automated Flow Analysis Instrument for Detecting Arsenic in Water.

In this paper the design and implementation of an embedded system based on Flow-Batch methodology with a Quartz Crystal Microbalance (QCM) sensor technology and a commercial FPGA admittance meter is presented to detect the presence of arsenic in water. The system's performance was evaluated with lab made samples and it is foresee that this open source automated flow instrument could help develop analytical methodologies for the future quantification of this analyte. A description of the components is presented and assembling and operation instructions are provided together with the dynamic range and linear regression coefficients for the line and R.

Estado epiléptico en adultos: caracterización de pacientes monitorizados por videoelectroencefalograma / Status epilecticus in adults: patient characterization by video-electroencephalogram monitoringby video-electroencephalogram monitoring

Introducción: el estado epiléptico (EE) es una afección potencialmente mortal con una morbilidad significativa en quienes sobreviven a esta entidad. Pacientes y métodos: estudio transversal descriptivo de corte analítico con el objetivo de describir la prevalencia y la relación con variables sociodemográficas, electroencefalográficas, imagenológicas y desenlaces clínicos en los pacientes hospitalizados que fueron monitorizado por videoelectroencefalograma (VEEG), en el Hospital de San José de Bogotá, Colombia, entre agosto 2017 y agosto 2019. Resultados: de los 135 pacientes monitorizados por VEEG, 27,47% cumplieron con los criterios para EE. La edad promedio fue 48 (DE: 19,56) años, 54,05% (n=20) de sexo masculino y 75,67% (n=28) sin antecedentes de epilepsia. Predominaron las manifestaciones motoras (70,27%, n=26), en 59,46% en el puntaje STESS fue desfavorable, 64,86% (n=24) requirió inducción a coma y monitorización en la unidad de cuidados intensivos(UCI) y 37,84% (n=14) fallecieron durante su estancia intrahospitalaria. Se encontró una relación entre EE, requerimiento de UCI y muerte intrahospitalaria. Conclusiones: la prevalencia del EE en pacientes hospitalizados monitorizados por VEEG fue cercana a 28%, lo que sugiere una relación entre EE, requerimiento de UCI y muerte intrahospitalaria.

Introduction: status epilepticus (SE) is a life-threatening disorder associated with high morbidity in SE survivors. Patients and methods: descriptive and analytical cross-sectional study with the aim to characterize the prevalence and relation with socio-demographic, electroencephalography and neuro-image variables as well as clinical outcomes of hospitalized patients who received video-electroencephalogram (video-EEG) monitoring, at Hospital de San José in Bogotá, Colombia, between August 2017 and August 2019. Results: of the 135 patients who received video-EEG monitoring, 27.47% met the criteria for SE. The median age was 48 (SD: 19.56) years, 54.05% (n=20) were men and 75.67% (n=28) had no history of epilepsy. There was a predominance of motor manifestations (70.27%, n=26), 59.46% had an unfavorable STESS score, while 64.86% (n=24) required induced coma and monitoring in the intensive care unit (ICU) and 37.84 % (n=14) died during their hospital stay. A relationship was found between SE, requiring admission to the ICU and in-hospital death. Conclusions: the prevalence of SE in hospitalized patients monitored by video-EEG was close to 28%, and a relationship between SE, requiring ICU admission and in-hospital death is suggested.

Efectos de un programa de ejercicio físico sobre variables bioquímicas y antropométricas en mujeres sedentarias de 20 a 40 años de una universidad de Armenia, Colombia, 2017 / Effects of a physical exercise program on biochemical and anthropometric variables in sedentary women of 20 to 40 years old from a university in the city of Armenia, Colombia, 2017

Resumen Introducción: El sedentarismo es uno de los principales factores de muerte prematura en todo el mundo, ya que incrementa el riesgo de padecer enfermedades crónicas no transmisibles. Diversas investigaciones han demostrado que las mujeres realizan menos actividad física que los hombres, por lo que es necesario desarrollar programas de ejercicio físico que permitan mayor adherencia al ejercicio, y determinar el impacto de este sobre variables bioquímicas. Objetivo: Evaluar el efecto del ejercicio físico sobre variables bioquímicas y antropométricas en mujeres sedentarias de 20 a 40 años. Materiales y métodos: El estudio fue cuasi experimental, tipo ensayo comunitario, en donde participaron 28 mujeres sedentarias. Se determinaron las variables antes y después de la aplicación de un programa de ejercicio físico; las variables evaluadas fueron composición corporal, perfil lipídico, creatinina, hemoglobina y plaquetas. Resultados: La edad promedio de las participantes fue de 26,73±12,2 años. Las variables que presentaron diferencias estadísticamente significativas con respecto a la primera muestra fueron el porcentaje adiposo, el porcentaje muscular, la creatinina, las plaquetas y la hemoglobina. Conclusiones: El programa de ejercicio físico, realizado en ausencia de control del plan alimenticio, logró modificar el porcentaje adiposo y muscular, la concentración de creatinina, hemoglobina y plaquetas; sin embargo, no disminuyó el colesterol total, ni los triglicéridos. MÉD.UIS.2020;33(2): 9-16.

Abstract Introduction: Sedentary lifestyle is one of the main factors of premature death worldwide, as it increases the risk of chronic noncommunicable diseases. Several investigations have shown that women perform less physical activity than men, therefore, it is necessary to develop physical exercise programs, which allow greater adherence to exercise, in addition to determining the impact of this on biochemical variables. Objective: To evaluate the effect of physical exercise on biochemical and anthropometric variables in sedentary women aged 20 to 40 years. Materials and methods: The study was a quasi-experimental, community trial type, where 28 sedentary women participated. The variables were determined before and after the application of a physical exercise program. The variables evaluated were body composition, lipid profile, creatinine, hemoglobin, and platelets. Results: The variables that presented statistically significant differences with respect to the first sample were adipose percentage, muscle percentage, creatinine, platelets, and hemoglobin. Conclusion: The physical exercise program in the absence of control of the diet plan modified the percentage adipose and muscular, the concentration of creatinine, hemoglobin, and platelets, however, it did not lower total cholesterol, nor triglycerides. MÉD.UIS.2020;33(2): 9-16.

Fusogenic properties of the Ectodomain of HCV E2 envelope protein.

The steps leading from hepatitis C virus (HCV) attachment to the hepatocytes to the fusion of viral and cellular membranes remain uncharacterized. In this regard, we have studied the mechanism underlying the HCV fusion process using liposomes and a truncated form of E2 protein lacking the transmembrane region, E2661 (amino acids 384-661). E2661 has been previously obtained by using the baculovirus expression system and shown to behave as an independent folding domain (M. Rodriguez-Rodriguez, D. Tello, B. Yelamos, J. Gomez-Gutierrez, B. Pacheco, S. Ortega, A.G. Serrano, D.L. Peterson, F. Gavilanes, Structural properties of the ectodomain of hepatitis C virus E2 envelope protein, Virus Res. 139 (2009) 91-99). This form has been used in lipid-protein interaction studies with different model vesicles, at different pHs and by employing a variety of fluorescent assays. The obtained results indicate that E2661 induces vesicle aggregation, lipid mixing and liposome leakage, reaching higher values in the presence of negatively charged phospholipids and cholesterol at acidic pH. Therefore, the results of these studies would be indicative of an HCV infection process through receptor mediated endocytosis. Accordingly, E2 might be important in the HCV initial infective steps, interacting with the target membranes and giving rise to their subsequent destabilization.

Expression and Ni-NTA-Agarose Purification of Recombinant Hepatitis C Virus E2Ectodomain Produced in a Baculovirus Expression System.

In this protocol, we describe the production and purification of the ectodomain of the E2661 envelope protein (amino acids 384-661) of the Hepatitis C virus, which plays a fundamental role in the entry of the virus into the host cell. This protein has been expressed in both prokaryotic and eukaryotic systems but in small quantities or without native protein characteristics. In our case, we use the Baculovirus expression system in insect cells. E2661 is secreted into the extracellular medium and purified by means of affinity chromatography a Ni-NTA-column because the protein has a tag of six histidines at its amino terminal end. The purified protein possesses a native-like conformation and it is produced in large quantities, around 5-6 mg per liter.

In vitro Membrane Interaction and Liposome Fusion Assays Using Recombinant Hepatitis C Virus Envelope Protein E2.

In order to study the mechanism underlying the Hepatitis C Virus (HCV) fusion process we have performed assays using phospholipid liposomes and a truncated form of E2 protein, E2661 (amino acids 384-661 of the HCV polyprotein) lacking the transmembrane region. E2661 has been previously generated by using the baculovirus expression system. This form has been used in lipid-protein interaction studies with different model vesicles at different pHs, and monitored using a variety of fluorescent assays. After the analysis of the results, we observed that E2661 is able to insert into lipid bilayers and to induce vesicle aggregation, lipid mixing and liposome leakage, showing higher values of membrane destabilization for negatively charged phospholipids at acidic pH. This is indicative of the role of E2 glycoprotein in the HCV initial infective steps, interacting with the target membranes and producing their destabilization.

Diagnóstico mediante EBUS lineal de infección pulmonar por Actinomyces graevenitzii / Diagnosis of Actinomyces graevenitzii Lung Infection using Linear EBUS

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The deletion of residues 268-292 of E1 impairs the ability of HCV envelope proteins to induce pore formation.

We have obtained a chimeric protein containing the ectodomains of hepatitis C virus (HCV) envelope proteins but lacking the region 268-292 of E1. All its structural properties are coincident with those of the corresponding full length chimera. The deleted and entire chimeras were compared in terms of their membrane destabilizing properties. No differences were found in their ability to induce vesicle aggregation and lipid mixing but the deleted chimera showed a reduced capacity to promote leakage. The role of the deletion was also studied by obtaining HCV pseudoparticles (HCVpp). Both E1 and E2, and also the E1 deleted mutant, were incorporated into HCVpp to a similar level. However, HCVpp containing the E1 deleted protein are almost unable to infect Huh7 cells. These results point to the involvement of the region 268-292 in the formation of pores in the membrane necessary for the complete fusion of the membranes.

Endofugas tipo 2 en una población tratada con endoprótesis Gore(R) Excluder: incidencia, persistencia y crecimiento del saco aneurismático / Type 2 endoleaks in a population treated with a Gore (R) Excluder endoprosthesis: incidence, persistence and aneurysmal sac growth

INTRODUCCIÓN: La endofuga tipo 2 (EF2) es la complicación más frecuente tras EVAR, con una tasa de crecimiento del saco variable y un tratamiento de resultados poco efectivos. Se pretende analizar la incidencia de EF2, su persistencia y evolución en una población homogénea, buscando variables predictoras de crecimiento del saco. MATERIAL Y MÉTODOS: Setenta EF2 (32,2%) detectadas en 217 EVAR aortoilíacos tratados con GORE(R) Excluder entre 2003 y 2011. Seguimiento clínico y con angiotomografía computarizada (media 32,5 meses). Análisis univariante de datos recogidos de forma prospectiva. Función de supervivencia de Kaplan-Meier y regresión de Cox. RESULTADOS: Un 90% de varones con edad media 75,5 ± 8 años y diámetro aórtico 59,6 ± 10 mm. El vaso aferente más frecuente fue una arteria lumbar (n = 42), con un 30% de endofugas complejas (n = 21). Veinticinco endofugas fueron transitorias (35,7%) y 45 persistentes, grupo este último con mayor número de mujeres (p = 0,044) y de colaterales aferentes al saco (1,5 ± 0,7 vs. 1,2 ± 0,4, p = 0,022). Crecimiento > 5 mm en un 38,6% de casos (mediana 8,5 mm, rango 5-24); once se trataron con embolización (éxito 63,6%). Las endofugas complejas no incrementaron el riesgo. El único predictor independiente de crecimiento en la regresión de Cox fue la edad (HR 2,71 IC 95% 1,01-7,19 p = 0,046). CONCLUSIONES: Las EF2 constituyen una complicación frecuente y sin factores predictores sólidos que permitan estratificar el riesgo de crecimiento del saco, por lo que es necesario un seguimiento exhaustivo

INTRODUCTION: Type 2 endoleaks (T2E) are the most common finding after endovascular aortic repair (EVAR), with a variable sac growth rate and a treatment with unpromising results. The aim of this study is to analyze the incidence of T2E and their evolution in a homogeneous population, seeking predictors for sac growth. MATERIAL AND METHODS: A total of 70 T2E (32.2%) were detected in 217 aorto-iliac EVAR treated with a GORE(R) Excluder endograft from 2003 to 2011. They were systematically followed-up with contrast enhanced tomography (mean 32.5 months). Univariate analysis of prospectively collected data; Kaplan-Meier survival functions and multivariate Cox regression. RESULTS: 90% of patients with T2E were males, with a mean age 75.8 ± 8 years, and mean aortic diameter 59.5 ± 10 mm. The most common persistent collateral vessel was a lumbar artery (n = 42), with 30% of complex T2E (n = 21). The endoleaks were transient in 25 cases (35.7%), and 45 persisted for more than 6 months, the latter with a higher percentage of women (p = 0 .044), and total number of afferent vessels (1.5 ± 0.7 vs. 1.2 ± 0.4, p = 0 .022). Sac growth over 5 mm was observed in 38.6% of cases (median 8.5 mm, rank 5-24), with eleven of those treated with trans-arterial or trans-lumbar embolization (63.6% success). Complex endoleaks did not show a higher risk profile. Age was the only independent risk factor in the Cox regression analysis (HR 2.71, 95% CI; 1.01-7.19 p = 0 .046). Conclusions : T2E are a frequent complication, with no solid predictive factors for stratifying sac growth risk, thus needing close surveillance

Study of the putative fusion regions of the preS domain of hepatitis B virus.

In a previous study, it was shown that purified preS domains of hepatitis B virus (HBV) could interact with acidic phospholipid vesicles and induce aggregation, lipid mixing and leakage of internal contents which could be indicative of their involvement in the fusion of the viral and cellular membranes (Núñez, E. et al. 2009. Interaction of preS domains of hepatitis B virus with phospholipid vesicles. Biochim. Biophys. Acta 17884:417-424). In order to locate the region responsible for the fusogenic properties of preS, five mutant proteins have been obtained from the preS1 domain of HBV, in which 40 amino acids have been deleted from the sequence, with the starting point of each deletion moving 20 residues along the sequence. These proteins have been characterized by fluorescence and circular dichroism spectroscopy, establishing that, in all cases, they retain their mostly non-ordered conformation with a high percentage of ß structure typical of the full-length protein. All the mutants can insert into the lipid matrix of dimyristoylphosphatidylglycerol vesicles. Moreover, we have studied the interaction of the proteins with acidic phospholipid vesicles and each one produces, to a greater or lesser extent, the effects of destabilizing vesicles observed with the full-length preS domain. The ability of all mutants, which cover the complete sequence of preS1, to destabilize the phospholipid bilayers points to a three-dimensional structure and/or distribution of amino acids rather than to a particular amino acid sequence as being responsible for the membrane fusion process.

High-yield production of a chimeric glycoprotein based on permuted E1 and E2 HCV envelope ectodomains.

In this report it is described for the first time the expression and purification of large quantities of a soluble and correctly folded chimeric recombinant protein, E2661E1340, containing the permuted Hepatitis C virus (HCV) glycoprotein ectodomains E1 (amino acids 192-340) and E2 (amino acids 384-661). Using the baculovirus/insect cell expression system, 8mg of secreted protein were purified from 1L of culture media, a yield 4 times higher than the described for its counterpart E1341E2661. This permuted chimeric protein is glycosylated and possesses a high tendency to self-associate. The fluorescence emission spectrum indicates that Trp residues occupy a relatively low hydrophobic environment. The secondary structure was determined by deconvolution of the far-UV circular dichroism spectrum yielding 13% α-helix structure, 49% extended structure and 38% non-ordered structure. E2661E1340 binds to antibodies present in human sera from HCV-positive patients, a binding that is blocked at different levels by a rabbit anti-E2661 antibody. All these structural and antigenic features of E2661E1340 are very similar to those described for E1340E2661, Thus, this high-yield isolated chimeric protein may be a valuable tool to study the first steps of the HCV infection.

Production and characterization of the ectodomain of E2 envelope glycoprotein of hepatitis C virus folded in the presence of full-length E1 glycoprotein.

Hepatitis C virus (HCV) envelope glycoproteins, E1 and E2, are involved in the first steps of virus infection. The E2 ectodomain can be produced as an isolated form (E2661). However, there is some concern about its proper conformation and the role that E1 can play as a chaperone for the folding of E2. In order to verify this fact we have expressed a chimeric protein (E1tmbE2) based on the full-length E1 sequence followed by the E2 ectodomain using the baculovirus-insect cells system. The E2 ectodomain is folded in the presence of the E1, proteolytically processed by cellular proteases and secreted to cell culture media (E2661p), while the E1 protein is retained into the cell due to its transmembrane sequence. The purification of E2661p from culture media was facilitated by a His tag introduced in its amino terminus. Both E2661 and E2661p glycoproteins shared very similar structural features, monitored by spectroscopic and antigenic studies. Moreover, their functional properties, tested by means of CD81 binding, were almost indistinguishable, indicating that the E2 ectodomain constitutes an independent folding unit.

Diagnóstico prenatal de gastrosquisis recurrente en Cali, Colombia: reporte de un caso y revisión de la literatura / Diagnosis of recurrent gastroschisis in Cali, Colombia: a case report and review of the literature

Objetivo: hacer una revisión de la literatura acerca de la fisiopatología en gastrosquisis, en especial lo relativo a las teorías de etiología genética de esta patología.Materiales y métodos: se presenta el caso clínico de un feto y posterior neonato con diagnóstico de gastrosquisis en una madre con historia previa de otro hijo con la misma patología. Se desarrolló una búsqueda de la literatura en la base de datos Medline/PubMed publicada en español e inglés durante el periodo comprendido entre enero de 2000 a enero de 2013. Se utilizaron los términos: gastrosquisis, pared abdominal, anomalías, genética. Se incluyeron artículos de revisión, reporte de casos y estudios de corte transversal.Resultados: se revisaron 90 artículos relacionados sobre los factores de riesgo implicados en el desarrollo de la gastrosquisis, y 23 artículos relacionados con gastrosquisis y genética. La gastrosquisis que se produce en los hermanos es rara, hay solo 14 casos publicados de gastrosquisis familiar en la literatura. Varios estudios epidemiológicos han identificado complejas interacciones entre factores ambientales y múltiples genes.Conclusión: la gastrosquisis constituye un evento poco frecuente y es de etiología incierta. Esta condición permanece como un dilema epidemiológico y patogenético. Se requiere investigación adicional para aclarar la etiología multifactorial de la gastrosquisis.

Objective: To review the literature on the pathophysiology of gastroschisis, in particular as refers to the theories of the genetic aetiology of this condition.Materials and methods: Presentation of a clinical case of a foetus and subsequent neonate diagnosed with gastroschisis, born to a mother with a prior history of another child with gastroschisis. A search was conducted in the Medline/Pubmed database of the literature published in Spanish and English during the period between January 2000 and January 2013. The terms used were gastroschisis, abdominal wall abnormalities, and genetics. Review articles, case reports and cross-sectional studies were included.Results: Overall, 90 articles relating to the risk factors involved in the development of gastroschisis and 23 articles relating to gastroschisis and genetics were reviewed. Gastroschisis occurring in siblings is rare, and there are only 14 cases of familial gastroschisis published in the literature. Several epidemiological studies have identified complex interactions between environmental factors and multiple genes.Conclusion: Gastroschisis is an infrequent event of uncertain aetiology. This condition continues to be an epidemiological and pathogenic dilemma. Additional research is required to elucidate the multifactorial aetiology of gastroschisis.

Fusogenic properties of the ectodomains of hepatitis C virus envelope proteins.

We have used an isolated chimeric protein E1340 E2661 that includes the ectodomains of the envelope proteins of hepatitis C virus to study its interaction with model membranes. E1340 E2661 has some of the membrane destabilization properties, vesicle aggregation, lipid mixing and the release of internal aqueous content, which have previously been ascribed to fusion proteins. The effects are preferentially produced on vesicles of acidic phospholipids which would indicate the importance of the electrostatic interactions. In fact, an increase of the ionic strength of the buffer induced a considerable decrease of the destabilizing properties. Moreover, fluorescence polarization studies show that the recombinant protein reduces the amplitude of the thermal transition of dimyristoylphosphatidylglycerol vesicles and increases the transition temperature at pH 5.0 in a dose-dependent manner, indicating its insertion into the bilayer. Furthermore, a decrease of the pH induces a conformational change in the protein structure as evidenced by fluorescence of tryptophan residues and 4,4'-bis(1-anilinonaphthalene-8-sulfonate). A model for the fusion of hepatitis C virus with the host cell membrane can be postulated. The dissociation of E1E2 dimers would uncover the fusion peptides which can then interact with the polar lipid heads of the outer leaflet of the lipid bilayer and next insert into the hydrophobic moiety producing the destabilization of the bilayer which finally leads to fusion.

Aneurismas rotos de la arteria gastroduodenal: tratamiento endovascular / The artery aneurysm gastroduodenal broken: endovascular treatment

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Ruptura prematura de membranas / Premature rupture of membranes

Los nacimientos prematuros son un gran problema en el mundo y la ruptura prematura de membranas contribuyen en cerca de un tercio a esa prematuridad. En Latino América aproximadamente uno de cada 7 nacimientos es prematuro y la ruptura de membranas y trastornos hipertensivos son la principal causa. Una vez confirmada la ruptura de membranas en especial las lejos del término, estamos ante una complicación obstétrica que amerita manejo muy específico y basado en pruebas (evidencia)...

Embarazo gemelar monocoriónico monoamniótico: Presentación de tres casos y revisión de la literatura / Monochorionic monoamniotic twin pregnancy: Three cases presented and review of the literature

Objetivo: realizar el reporte de casos de embarazo gemelar monocoriónico monoamniótico con entrecruzamiento de cordones y hacer una revisión de la literatura respecto al pronóstico de este tipo de gestación, seguimiento prenatal e intervenciones de manejo hasta su finalización. Materiales y métodos: se presenta el reporte de tres casos que ocurrieron en el Hospital Universitario del Valle, Cali, Colombia, centro de referencia de nivel III del suroccidente colombiano, el cual atiende población embarazada de alto riesgo obstétrico. Se desarrolló una búsqueda de la literatura en la base de datos Medline/Pubmed publicada en español e inglés durante el periodo comprendido entre enero de 1990 a mayo 2013. Se utilizaron los términos: “gemelos”, “gemelos monocigóticos”, “embarazo múltiple”, “embarazo gemelar”. Se incluyeron artículos de revisión, reporte de casos y estudios de corte transversal. Resultados: se revisaron 23 artículos de los cuales 5 correspondieron a artículos de revisión, 7 reportes de casos y 11 estudios de corte trasversal. La información acerca de las tasas de mortalidad, evaluación prenatal, seguimiento, manejo de las complicaciones, momento y modo del nacimiento en gemelos monoamnióticos es controversial. Conclusión: la gestación gemelar monocorial monoamniótica constituye un evento poco frecuente. Esta condición está asociada con múltiples complicaciones obstétricas que incluyen la muerte fetal relacionada con accidentes de los cordones umbilicales (entrecruzamientos). El objetivo del cuidado prenatal constituye la prevención de la mortalidad fetal, por lo que se sugiere la realización continua de pruebas de bienestar fetal. Se ha propuesto la terminación del embarazo en la semana 34 de gestación por operación cesárea, previa administración de esteroides.

Objective: To report cases of monochorionic monoamniotic twin pregnancy with cord entanglement, and conduct a review of the literature regarding the prognosis of this type of gestation, prenatal follow-up and management interventions through to delivery. Materials and methods: We report 3 cases that presented to Hospital Universitario del Valle, Cali, Colombia, a level III referral center in Southwestern Colombia that provides healthcare services to pregnant women with a high obstetric risk. We conducted a search in the literature in the Medline/ Pubmed database published in Spanish and English between January 1990 and May 2013. The terms used were “twins”, “monozygotic twins”, “multiple pregnancy”, “twin pregnancy”. Review articles, case reports and cross-sectional studies were included. Results: Overall, 23 articles were reviewed, including 5 review articles, 7 case reports and 11 cross-sectional studies. Information on mortality rates, pre-natal assessment, follow-up, management of complications, time and mode of birth in monoamniotic twins is controversial. Conclusion: Monochorial monoamniotic twin pregnancy is an infrequent event. This condition is associated with multiple obstetric complications, including fetal demise associated with umbilical cord accidents (entanglement). The goal of prenatal care is to prevent fetal death, hence the suggestion of continuous testing for fetal wellbeing. Termination of pregnancy has been proposed at week 34 of gestation through cesarean section after steroid administration.

Exclusión de pseudoaneurismas de la aorta infrarrenal utilizando extensores aórticos / Exclusion of infrarenal aorta pseudoaneurysms using aortic extensions

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