Browsing by Author "Vera Lizcano, Omaira"
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Item Acumulación de mercurio y plomo, en el bivalvo Anadara tuberculosa, entre los años 2016 y 2018 en la desembocadura del río Dagua, Pacífico Colombiano(Universidad Santiago de Cali, 2019) Lucero Rincón, Carlos Hernán; Vera Lizcano, OmairaPollution due to mercury and lead has caused great concern in international entities due to the loss of biodiversity in coastal ecosystems and damage to health. In order to evaluate the presence of mercury and lead in the mouth of the Colombian Dagua-Pacific river, as it is an ecosystem of great ecological and economic importance for the region, seven samplings were carried out between July 2016 and January 2018, sediment samples were obtained and physicochemical parameters of the water in the area were measured. Specimens of the bivalve, Anadara tuberculosa, were used to determine the concentration of mercury and lead in tissues and for bioassays with mercury, due to its ability to bioaccumulate metals. A mean mercury concentration of 0.57± 0.74 mg/kg and lead 0.87 mg/kg ± 0.68 in sediment were found, with maximum values of 1.96 mg/kg Hg and 2.05 mg/kg Pb. The presence of mercury in sediments and water is positively related to the concentrations of this metal in organisms. Bioassays with the bivalve A. tuberculosa, allowed to conclude that at low mercury exposure concentrations (0.25 ppm), lesions are generated in animal tissue, mainly in sexual cells. The high concentrations of mercury and lead found in the organisms exceed the maximum permitted concentration established in Colombia for mercury (0.5 mg/kg) and lead (0.20 mg/kg). In addition, the contamination factor for mercury (FC =228000 μg/g) and lead (FC =1242.85 μg/g) are considered very high, as is the potential contamination index for mercury (CP=3.44 μg/g). This allows us to infer that the presence of metals in the tissue of these bivalves present in the mouth of the Dagua river can generate alterations in the ecosystem with possible consequences on human health due to the consumption of these foods.Item Caracterización molecular y epidemiológica de una cohorte de casos de microfilariasis canina identificados en Cali y municipios cercanos(Universidad Santiago de Cali, 2020) Espinosa Rosero, Nathaly; Rosero López, Ángelo Enrique; Castellanos Sánchez, Angélica María; Vera Lizcano, OmairaFilariae are nematodes that affect different mammals. In canines, the filariae first larval stage is called microfilaria that can be observed circulating in peripheral blood. Dirofilaria immitis is the most prevalent specie worldwide, causing heartworm disease, that can be fatal in canines and affect humans. The objective of this study was the identification of cases of canines with filariasis in Cali (Colombia) and close localities in of one-year period, detected by microscopy, serological methods and the determination of the species by the molecular method PCR–RFLP. In eight cases PCRsequencing was performed. As a result, a total of 102 cases of canine filariasis were detected, of which 82 were molecularly analyzed, finding that 55 (67%) of them corresponded to the Acantacheilonema reconditum specie. The filarial species in the remaining cases could not be molecularly identified, probably due to low parasitaemia by the time of blood sampling. The filariasis cases were statistically associated with males who presented clinical signs of anemia, with low levels of hemoglobin and hematocritItem Genetic diversity of chloroquine-resistant Plasmodium vivax parasites from the western Brazilian Amazon(Memorias do Instituto Oswaldo Cruz, 2014) Vera Lizcano, Omaira; Resende, Sarah Stela; Chehuan, Yonne F.; Guimarães Lacerda, Marcus Vinicius; A. Brito, Cristiana F.; Zalis, Mariano G.The molecular basis of Plasmodium vivax chloroquine (CQ) resistance is still unknown. Elucidating the molecular background of parasites that are sensitive or resistant to CQ will help to identify and monitor the spread of resistance. By genotyping a panel of molecular markers, we demonstrate a similar genetic variability between in vitro CQ-resistant and sensitive phenotypes of P. vivax parasites. However, our studies identified two loci (MS8 and MSP1-B10) that could be used to discriminate between both CQ-susceptible phenotypes among P. vivax isolates in vitro. These preliminary data suggest that microsatellites may be used to identify and to monitor the spread of P. vivax-resistance around the world.Item Identification, ecological indices and management of mosquitoes (Diptera: Culicidae) influencing environmental education processes in Colombian high schools(Springer Science and Business Media Deutschland GmbH, 2022-04) Bedoya Rodríguez, Francisco Javier; Guevara Fletcher, Carlos Eduardo; Vera Lizcano, OmairaVector-borne diseases annually cause more than 700,000 deaths worldwide. In Colombia, infectious diseases are prevalent, being the Municipality of Santander de Quilichao (Cauca district) one of the most affected areas. This study aimed (a) to determine the abundance of species of mosquitoes with the potential capacity to transmit infectious diseases, in a school located in the Cauca district and (b) to teach students self-care and care for the environment to protect themselves from vector-borne diseases. During 2019 and 2020, in a dry and rainy season, manual collection of mosquitoes in four sites of the institution was conducted. Ecological statistical analyses were carried out. Mosquito species were grouped by similarity (abundance) using a dendrogram by area and a species rarefaction curve. A sociodemographic survey on knowledge, attitudes, and practices related to vector-borne diseases was carried out. An educational booklet was developed, and its impact was validated through the nonparametric Wilcoxon test. In total, 108 specimens were captured from four species: Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and Psorophora ferox. The greater presence of mosquitos was during the rainy season, being Aedes aegypti the most abundant species. According to Likert’s analysis, 59.6% of the students had a very favorable attitude toward the subject; the educational campaign significantly improved knowledge, attitudes, and practices of the students. Finally, the study presents entomological data of interest in public health. That makes it possible to establish prevention and control measures for vector-borne diseases in high schools, through environmental education.Item Plasmodium vivax Gametocytes Adherence to Bone Marrow Endothelial Cells(2021) Salazar Alvarez, Luis Carlos; Vera Lizcano, Omaira; da Silva Barros, Dayanne Kamylla Alves; Baia-da-Silva, Djane Clarys; Monteiro, Wuelton Marcelo; Pimenta, Paulo Filemon Paolluci; de Lacerda, Marcus Vinicius Guimarães; Costa, Fabio Trindade Maranhão; Lopes, Stefanie Costa PintoIn a Plasmodium vivax infection, it was shown a proportionally increased on gametocyte distribution within the bone marrow aspirant, suggesting a role of this organ as a reservoir for this parasite stage. Here, we evaluated the ex vivo cytoadhesive capacity of P. vivax gametocytes to bone marrow endothelial cells (HBMEC) and investigated the involvement of some receptors in the cytoadhesion process by using transfected CHO cells (CHO-ICAM1, CHO-CD36 and CHO-VCAM), wild type (CHO-K1) or deficient in heparan and chondroitin sulfate (CHO-745). Ex-vivo cytoadhesion assays were performed using a total of 44 P. vivax isolates enriched in gametocyte stages by Percoll gradient in the different cell lines. The majority of isolates (88.9%) were able to adhere to HBMEC monolayer. ICAM1 seemed to be the sole receptor significantly involved. CD-36 was the receptor with higher adhesion rate, despite no significance was noticed when compared to CHO-745. We demonstrated that gametocyte P. vivax adheres ex vivo to bone marrow endothelial cells. Moreover, P. vivax gametocytes display the ability to adhere to all CHO cells investigated, especially to CHO-ICAM1. These findings bring insights to the comprehension of the role of the bone marrow as a P. vivax reservoir and the potential impact on parasite transmission to the vectorItem Plasmodium, Trypanosoma y Salmonella: marcadores moleculares(Editorial Universidad Santiago de Cali, 2020-04-13) Vera Lizcano, Omaira; Grassini Gomes, Carla Sodré; Gustavo Zalis, Mariano; Tovar Acero, Nubia Catalina; Yasnot Acosta, Maria Fernanda; Castellanos Sánchez, Angélica; Loaeza Reyes, Karen Julissa; Moreno Rodríguez, Adriana; Torres Rosas, Rafael; Argueta Figueroa, Liliana; Zenteno Galindo, Edgar Arturo; Hernandez Cruz, Pedro Antonio; Gallegos Velasco, Itandehui Belem; Pérez Cervera, Tobana; Díez Mejía, Andrés Felipe; Marín Villa, Marcel; Varela Miranda, Rubén Eduardo; Gaviria Cantin, Tania; Balsalobre Parra, Carlos;Realizar este libro de revisión con temas de investigación actual, sin mostrar resultados, sino antecedentes del proceso investigativo, nos ha permitido contar de forma extensa los fundamentos teóricos de donde se genera la nueva investigación básica y la fundamentación para la investigación clínica. Este libro ha sido escrito por investigadores que han recopilado la información a través de sus carreras investigativas y que han visto cómo evoluciona el conocimiento gracias a la aplicación de la biología molecular como herramienta en el estudio de las enfermedades infecciosas. Cada capítulo del libro contiene información completa del conocimiento, hasta el día de hoy, de cada uno de los tópicos tratados; el tema en común son los biomarcadores moleculares de tres agentes infecciosos de importancia médica: Plasmodium spp., Trypanosoma spp. y Salmonella spp., agentes causales de enfermedades infecciosas de alta prevalencia en el mundo; las complicaciones que de ellas se derivan, como la sepsis y la falla multiorgánica, son importantes causas de morbilidad y mortalidad en los individuos afectados.Item The role of the peritrophic matrix and red blood cell concentration in Plasmodium vivax infection of Anopheles aquasalis.(Parasites and Vectors, 2018) Baia-da-Silva, Djane Clarys; Salazar Alvarez, Luis Carlos; Vera Lizcano, Omaira; Maranhão Costa, Fabio Trindade; Costa Pinto Lopes, Stefanie; Silva Orfanó, Alessandra; Oliveira Pascoal, Denner; Nacif-Pimenta, Rafael; Cabral Rodriguez, Iria; Barbosa Guerra, Maria das Graças Vale; Guimarães Lacerda, Marcus Vinicius; Costa Secundino, Nagila Francinete; Monteiro, Wuelton Marcelo; Paolucci Pimenta, Paulo FilemonBackground: Plasmodium vivax is predominant in the Amazon region, and enhanced knowledge of its development inside a natural vector, Anopheles aquasalis, is critical for future strategies aimed at blocking parasite development. The peritrophic matrix (PM), a chitinous layer produced by the mosquito midgut in response to blood ingestion, is a protective barrier against pathogens. Plasmodium can only complete its life-cycle, and consequently be transmitted to a new host, after successfully passing this barrier. Interestingly, fully engorged mosquitoes that had a complete blood meal form a thicker, well-developed PM than ones that feed in small amounts. The amount of red blood cells (RBC) in the blood meal directly influences the production of digestive enzymes and can protect parasites from being killed during the meal digestion. A specific study interrupting the development of the PM associated with the proteolytic activity inhibition, and distinct RBC concentrations, during the P. vivax infection of the New World malaria vector An. aquasalis is expected to clarify whether these factors affect the parasite development. Results: Absence of PM in the vector caused a significant reduction in P. vivax infection. However, the association of chitinase with trypsin inhibitor restored infection rates to those of mosquitoes with a structured PM. Also, only the ingestion of trypsin inhibitor by non-chitinase treated mosquitoes increased the infection intensity. Moreover, the RBC concentration in the infected P. vivax blood meal directly influenced the infection rate and its intensity. A straight correlation was observed between RBC concentrations and infection intensity. Conclusions: This study established that there is a balance between the PM role, RBC concentration and digestive enzyme activity influencing the establishment and development of P. vivax infection inside An. aquasalis. Our results indicate that the absence of PM in the midgut facilitates digestive enzyme dispersion throughout the blood meal, causing direct damage to P. vivax. On the other hand, high RBC concentrations support a better and thick, well-developed PM and protect P. vivax from being killed. Further studies of this complex system may provide insights into other details of the malaria vector response to P. vivax infection.Item Rosette formation by Plasmodium vivax gametocytes favors the infection in Anopheles aquasalis(Frontiers Media SA, 2023-02-15) Salazar Alvarez, Luis Carlos; Carneiro Barbosa, Vanessa; Vera Lizcano, Omaira; Baia da Silva, Djane Clarys; Gonçalves Santana, Rosa Amélia; Fabbri, Camila; Paoluci Pimenta, Paulo Filemon; Monteiro, Wuelton Marcelo; Albrecht, Letusa; Guimarães de Lacerda, Marcus Vinicius; Trindade Maranhão Costa, Fabio; Costa Pinto Lopes, StefaniePlasmodium vivax is a public health problem and the most common type of malaria outside sub-Saharan Africa. The capacity of cytoadhesion, rosetting, and liver latent phase development could impact treatment and disease control. Although the ability to P. vivax gametocyte develop rosetting is known, it is not yet clear which role it plays during the infection and transmission process to the mosquito. Here, we used ex vivo approaches for evaluate the rosetting P. vivax gametocytes capacity and we have investigated the effect of this adhesive phenotype on the infection process in the vector Anopheles aquasalis mosquito. Rosette assays were performed in 107 isolates, and we have observed an elevated frequency of cytoadhesive phenomena (77,6%). The isolates with more than 10% of rosettes have presented a higher infection rate in Anopheles aquasalis (p=0.0252). Moreover, we found a positive correlation between the frequency of parasites in rosetting with the infection rate (p=0.0017) and intensity (p=0.0387) in the mosquito. The disruption of P. vivax rosette formation through mechanical rupture assay confirmed the previously findings, since the paired comparison showed that isolates with disrupted rosettes have a lower infection rate (p<0.0001) and intensity (p=0.0003) compared to the control group (no disruption). Herein we have demonstrated for the first time a potential effect of the rosette phenomenon on the infection process in the mosquito vector An.