Examinando por Autor "Martínez Gutiérrez, Marlen"
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- PublicaciónAcceso abiertoAntiviral effect of compounds derived from the seeds of Mammea americana and Tabernaemontana cymosa on Dengue and Chikungunya virus infections(2017-01-18) Gómez Calderón, Cecilia; Mesa Castro, Carol; Robledo, Sara; Gómez Rangel, Sergio-Yebrail; Bolivar Avila, Santiago; Diaz Castillo, Fredyc; Martínez Gutiérrez, MarlenBackground The transmission of Dengue virus (DENV) and Chikungunya virus (CHIKV) has increased worldwide, due in part to the lack of a specific antiviral treatment. For this reason, the search for compounds with antiviral potential, either as licensed drugs or in natural products, is a research priority. The objective of this study was to identify some of the compounds that are present in Mammea americana (M. americana) and Tabernaemontana cymosa (T. cymosa) plants and, subsequently, to evaluate their cytotoxicity in VERO cells and their potential antiviral effects on DENV and CHIKV infections in those same cells. Methods Dry ethanolic extracts of M. americana and T. cymosa seeds were subjected to open column chromatographic fractionation, leading to the identification of four compounds: two coumarins, derived from M. americana; and lupeol acetate and voacangine derived from T. cymosa.. The cytotoxicity of each compound was subsequently assessed by the MTT method (at concentrations from 400 to 6.25 μg/mL). Pre- and post-treatment antiviral assays were performed at non-toxic concentrations; the resulting DENV inhibition was evaluated by Real-Time PCR, and the CHIKV inhibition was tested by the plating method. The results were analyzed by means of statistical analysis. Results The compounds showed low toxicity at concentrations ≤ 200 μg/mL. The compounds coumarin A and coumarin B, which are derived from the M. americana plant, significantly inhibited infection with both viruses during the implementation of the two experimental strategies employed here (post-treatment with inhibition percentages greater than 50%, p < 0.01; and pre-treatment with percentages of inhibition greater than 40%, p < 0.01). However, the lupeol acetate and voacangine compounds, which were derived from the T. cymosa plant, only significantly inhibited the DENV infection during the post-treatment strategy (at inhibition percentages greater than 70%, p < 0.01). Conclusion In vitro, the coumarins are capable of inhibiting infection by DENV and CHIKV (with inhibition percentages above 50% in different experimental strategies), which could indicate that these two compounds are potential antivirals for treating Dengue and Chikungunya fever. Additionally, lupeol acetate and voacangine efficiently inhibit infection with DENV, also turning them into promising antivirals for Dengue fever.
- PublicaciónAcceso abiertoCo-circulation and simultaneous co-infection of dengue, chikungunya, and zika viruses in patients with febrile syndrome at the Colombian-Venezuelan border(2018-01-30) Carrillo Hernández, Marlen Yelitza; Gómez Rangel, Sergio-Yebrail; Ruiz Saenz, Julian; Jaimes Villamizar, Lucy; Martínez Gutiérrez, MarlenBackground: In Colombia, the dengue virus (DENV) has been endemic for decades, and with the recent entry of the chikungunya virus (CHIKV) (2014) and the Zika virus (ZIKV) (2015), health systems are overloaded because the diagnosis of these three diseases is based on clinical symptoms, and the three diseases share a symptomatology of febrile syndrome. Thus, the objective of this study was to use molecular methods to identify their co-circulation as well as the prevalence of co-infections, in a cohort of patients at the Colombian-Venezuelan border. Methods: A total of 157 serum samples from patients with febrile syndrome consistent with DENV were collected after informed consent and processed for the identification of DENV (conventional PCR and real-time PCR), CHIKV (conventional PCR), and ZIKV (real-time PCR). DENV-positive samples were serotyped, and some of those positive for DENV and CHIKV were sequenced. Results: Eighty-two patients were positive for one or more viruses: 33 (21.02%) for DENV, 47 (29.94%) for CHIKV, and 29 (18.47%) for ZIKV. The mean age range of the infected population was statistically higher in the patients infected with ZIKV (29.72 years) than in those infected with DENV or CHIKV (21.09 years). Both co-circulation and coinfection of these three viruses was found. The prevalence of DENV/CHIKV, DENV/ZIKV, and CHIKV/ZIKV co-infection was 7.64%, 6.37%, and 5.10%, with attack rates of 14.90, 12.42, and 9.93 cases per 100,000 inhabitants, respectively. Furthermore, three patients were found to be co-infected with all three viruses (prevalence of 1.91%), with an attack rate of 4.96 cases per 100,000 inhabitants. Conclusion: Our results demonstrate the simultaneous co-circulation of DENV, CHIKV, ZIKV and their co-infections at the Colombian-Venezuelan border. Moreover, it is necessary to improve the differential diagnosis in patients with acute febrile syndrome and to study the possible consequences of this epidemiological overview of the clinical outcomes of these diseases in endemic regions.
- PublicaciónAcceso abiertoEvaluación in vitro del efecto antiviral de compuestos derivados de plantas de la Región Caribe Colombiana sobre la infección por Virus Dengue y Virus Chikungunya(Bucaramanga : Universidad de Santander, 2016, 2016-10-21) Gómez Calderón, Cecilia; Martínez Gutiérrez, MarlenThe transmission of Dengue virus (DENV) and Chikungunya virus (CHIKV) has increased worldwide, due in part to the lack of a specific antiviral treatment. For this reason, the search for compounds with antiviral potential, either as licensed drugs or in natural products, is a research priority. The objective of this study was to identify some of the compounds that are present in Mammea americana (M. americana) and Tabernaemontana cymosa (T. cymosa) plants and, subsequently, to evaluate their cytotoxicity in VERO cells and their potential antiviral effects on DENV and CHIKV infections in those same cells. Dry ethanolic extracts of M. americana and T. cymosa seeds were subjected to open column chromatographic fractionation, leading to the identification of four compounds (with two coumarins, namely lupeol acetate, and voacangine). The cytotoxicity of each compound was subsequently assessed by the MTT method (at concentrations from 400 to 6.25 μg/mL). Pre- and post-treatment antiviral assays were performed at non-toxic concentrations; the resulting DENV inhibition was evaluated by Real-Time PCR, and the CHIKV inhibition was tested by the plating method. The results were analyzed by means of statistical analysis. The compounds showed low toxicity at concentrations ≤ 200 μg/mL. The compounds coumarin A and coumarin B, which are derived from the M. americana plant, significantly inhibited infection with both viruses during the implementation of the two experimental strategies employed here (posttreatment with inhibition percentages greater than 50%, p < 0.01; and pre-treatment with percentages of inhibition greater than 40%, p < 0.01). However, the lupeol acetate and voacangine compounds, which were derived from the T. cymosa plant, only significantly inhibited the DENV infection during the post-treatment strategy (at inhibition percentages greater than 70%, p < 0.01). In vitro, the coumarins are capable of inhibiting infection by DENV and CHIKV (with inhibition percentages above 50% in different experimental strategies), which could indicate that these two compounds are potential antivirals for treating Dengue and Chikungunya fever. Additionally, lupeol acetate and voacangine efficiently inhibit infection with DENV, also turning them into promising antivirals for Dengue fever.
- PublicaciónAcceso abiertoIdentificación de Arbovirus circulantes en una cohorte de pacientes con síndrome febril en el municipio de Villa del Rosario, Norte de Santander(Bucaramanga : Universidad de Santander, 2016, 2016-09-21) Carrillo Hernández, Marlen Yelitza; Martínez Gutiérrez, Marlen; Ruiz Saenz, JulianLos Virus Dengue (DENV), el Virus del Chikungunya (CHIKV) y el Virus Zika (ZIKV) son trasmitidos por el mismo vector, lo que resulta en la co-circulación de estos tres virus en las mismas regiones geográficas, aumentando la posibilidad de coinfecciones. El objetivo de este estudio fue identificar las cepas circulantes y calcular la prevalencia de co-infecciones en el municipio Villa del Rosario (Norte de Santander). Para lograr esto, con previo aval de bioética y consentimiento informado, se recolectaron muestras de suero de pacientes que presentaban fiebre menor de 7 días y con diagnóstico clínico compatible con alguna de estas tres enfermedades virales. Se extrajo el ARN de los sueros, posteriormente se realizó la retrotranscripción (RT) para obtener el cDNA, el cual fue utilizado como plantilla para la identificación de DENV y CHIKV (por PCR convencional) y ZIKV (por Real Time PCR). Las muestras positivas para DENV fueron serotipificadas y algunas muestras positivas para DENV y CHIKV fueron secuenciadas. Los resultados demostraron que 82 pacientes fueron positivos para uno o más virus: 33 (21.02%) para DENV, 47 (29.94%) para CHIKV y 29 (18.47%) para ZIKV. Adicionalmente, se encontró co-infección entre ellos: la prevalencia de co-infección DENV/CHIKV, DENV/ZIKV y CHIKV/ZIKV fue del 7.64%, 6.37% y 5.10%, con tasas de ataque de 14.90, 12.42 y 9.93 casos por cada 100.000 habitantes, respectivamente. Por otro lado, se encontraron tres pacientes co-infectados con los tres virus (prevalencia del 1.91%) con una tasa de ataque de 4.96 casos por 100.000 habitantes. Este estudio demuestra la simultánea co-circulación de DENV, CHIKV y ZIKV y sus co-infecciones en la región nororiente de Colombia.
- PublicaciónAcceso abiertoPrevalence and molecular typing of rotavirus in children with acute diarrhoea in Northeastern Colombia(Revista do Instituto de Medicina Tropical de Sao Paulo, 2019-06-01) Martínez Gutiérrez, Marlen; Arcila Quiceno, Victor; Trejos Suárez, Juanita; Ruiz Saenz, Julian; CLINIUDESAfter the introduction of the rotavirus vaccine, the number of rotavirus-associated deaths and the predicted annual rotavirus detection rate had slightly declined worldwide. Taking in account that in Colombia, Rotarix vaccine was introduced in 2009, the purpose of this study was to evaluate the presence of rotavirus A in children under five years who were treated for acute diarrhoea in Bucaramanga, Colombia and, moreover, to determine the genotypes of rotavirus present in those children. We performed an analytical cross-sectional study of rotavirus A in faecal samples from children up to five years of age. Stool samples were screened for rotavirus A using a lateral-flow immunochromatographic assay and confirmed using a VP6 sandwich ELISA. Genotyping of rotavirus A-positive samples was performed by PCR and sequencing of VP7 and VP4 genes. The overall prevalence of rotavirus was 30.53% (95% confidence interval [CI] 21.2 - 39.7). Most of the children with rotavirus (86.2%) had received two doses of the rotavirus vaccine. G3 strains accounted for the vast majority of cases (82.8%), followed by G12 strains (13.8%) and G3/G9 coinfections (3.4%). Among the P genotypes, P[8] was the most prevalent (69%), followed by P[9] (31%). The most common G[P] genotype combination was G3P[8], followed by G3P[9]. The main finding in this study was that rotavirus, in a Colombian region, is still an important pathogen in children under five years old, previously vaccinated. The results showed that different factors, such as kindergarten attendance, could explain the epidemiology and transmission of rotavirus in Bucaramanga.